Master's thesis of Applied Science (Photography): Mechanisms of controlling colour and aesthetic appearance of the photographic salt print

MECHANISMS OF CONTROLLING

COLOUR AND AESTHETIC

APPEARANCE OF THE

PHOTOGRAPHIC SALT PRINT

A thesis submitted in fulfilment of the requirements for

the degree of Master of Applied Science (Photography)

Eleanor (Ellie) D. Young

School of Applied Sciences

Science, Engineering and Technology Portfolio

RMIT University

February 2008

D E C LARAT ION

Th i s th esi s con tai n s n o mat er i al wh i ch h as been

accepte d for th e awar d of an y o th er degr ee or di pl oma

i n an y u n i ver si ty an d, to th e best of my kn o wl edge an d

bel i ef, con tai n s n o mater i al pr evi ou sl y pu bl i sh ed or

wr i tten by an oth er per son , ex cep t wh er e du e r efer en ce i s

made i n th e t ex t of th e th e si s. Th i s th esi s con tai n s n o

wor k th at was per for med p r i or to th e offi ci al

Eleanor (Ellie) D. Young

com men cem en t date of th i s r esea r ch pr oject.

i i

CONTENTS

D E C L A R A T I O N . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . I I

L I S T O F F I G U R E S . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . I V

L I S T O F C H A R T S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . V I

L I S T O F T A B L E S . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . V I

A C K N O W L E D G E ME N T S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . V I I I

A B S T R A C T . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

I N T R O D U C T I O N . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

B A C K G R O U N D . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

R E S E A R C H D E S I G N . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

CH AP T ER 1 T H E FO RM U L AS ................................................................ 15

CH AP T ER 2 T H E P AP ER ....................................................................... 28

CH AP T ER 3 CO AT IN G T H E P AP ER ......................................................... 38

CH AP T ER 4 T H E NEG AT I V E .................................................................. 45

CH AP T ER 5 EX P O S IN G T H E P RINT ........................................................ 60

CH AP T ER 6 P RO C ES S ING T H E P RIN T ..................................................... 71

CH AP T ER 7 D IS CU S S IO N ..................................................................... 84

CH AP T ER 8 CO NCLU S IO N .................................................................... 89

A P P E N D I X 1 S A L T F O R M U L A S . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91

A P P E N D I X 2 T O N E R F O R M U L A S . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95

A P P E N D I X 3 D E V E L O P E R A N D F I X E R F O R M U L A S . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98

G L O S S A R Y . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101

R E F E R E N C E S . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106

A T T A C H M E N T 1 C D : M I S C E L L A N E A P H O T O G E N IC A . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 108

A T T A C H M E N T 2 T H E S A L T P R I N T M A N U A L . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 109

i i i

F i g u r e 1 - 1 S o d i u m C h l o r i d e + s i l v e r n i t r a t e . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 7

F i g u r e 1 - 2 A m m o n i u m C h l o r i d e + s i l v e r n i t r a t e . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 7

F i g u r e 1 - 3 S o d i u m C h l o r i d e + s i l v e r n i t r a t e + s o d i u m c i t r a t e . . . . . . . . . . . . . . . . . . . . . . 1 7

F i g u r e 1 - 4 A m m o n i u m C h l o r i d e + s i l v e r n i t r a t e + s o d i u m c i t r a t e . . . . . . . . . . . . . . . . 1 7

F i g u r e 1 - 5 S o d i u m C h l o r i d e + s i l v e r n i t r a t e + P o t a s s i u m D i c h r o m a t e . . . . . . . . . . . 1 7

F i g u r e 1 - 6 A m m o n i u m C h l o r i d e + s i l v e r n i t r a t e + P o t a s s i u m

D i c h r o m a t e . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 7

F i g u r e 1 - 7 S i l v e r c h l o r i d e % d i f f e r e n c e s . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 0

F i g u r e 1 - 8 0. 2 % G e l a t i n B i n d e r . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 3

F i g u r e 1 - 9 2% Ge l a t i n B i n d e r . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 3

F i g u r e 1 - 10 A r r o w r o o t . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 3

F i g u r e 1 - 11 A l b u m e n . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 3

F i g u r e 1 - 12 B i n d e r s u r f a c e s . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 4

F i g u r e 1 - 13 M e a s l e s . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 6

F i g u r e 1 - 14 S i l v e r N i t r a t e V a r i a n c e s . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 6

F i g u r e 2 - 1 B e r g g e r P a p e r H i g h M a g n i f i c a t i o n s . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 2

F i g u r e 2 - 2 T a l b o t P a p e r H i g h M a g n i f i c a t i o n s . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 3

F i g u r e 2 - 3 A r c h e s P l a t i n e H i g h M a g n i f i c a t i o n s . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 3

F i g u r e 2 - 4 F a b r i a n o A r t i s t i c o H i g h M a g n i f i c a t i o n s . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 3

F i g u r e 2 - 5 B u x t o n P a p e r H i g h M a g n i f i c a t i o n s . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 3

F i g u r e 2 - 6 B e r g g e r P a p e r . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 4

F i g u r e 2 - 7 T a l b o t P a p e r . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 4

F i g u r e 2 - 8 A r c h e s P l a t i n e . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 4

L I S T O F F I G U R E S

i v

F i g u r e 2 - 9 F a b r i a n o A r t i s t i c o . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 4

F i g u r e 2 - 1 0 B u x t o n P a p e r . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 4

F i g u r e 3 - 1 G l a s s R o d . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 9

F i g u r e 4 - 1 A N e g a t i v e a n d B S a l t P r i n t . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 9

F i g u r e 4 - 2 P M K T o n e s i n D i g i t a l N e g a t i v e s . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 5

F i g u r e 4 - 3 S p e c t r a l N e g a t i v e s . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 7

F i g u r e 5 - 1 C u t - o f f F i l t e r T e s t s . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 1

F i g u r e 5 - 3 B r o n z i n g S u r f a c e D e t a i l . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 8

F i g u r e 5 - 2 S e l f M a s k i n g . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 8

F i g u r e 5 - 4 B r o n z i n g h i g h M a g n i f i c a t i o n . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 9

F i g u r e 6 - 1 S o d i u m C h l o r i d e – n o T o n e r . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 5

F i g u r e 6 - 2 S o d i u m C h l o r i d e – Go l d B o r a x T o n e r . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 5

F i g u r e 6 - 3 S o d i u m C h l o r i d e - Go l d T h i o c y a n a t e . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 5

F i g u r e 6 - 4 S o d i u m C h l o r i d e – P l a t i n u m . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 5

F i g u r e 6 - 5 S o d i u m C h l o r i d e - Go l d B o r a x a n d P l a t i n u m . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 5

F i g u r e 6 - 6 A m m o n i u m C h l o r i d e + G e l a t i n - N o T o n e r . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 5

F i g u r e 6 - 7 A m m o n i u m C h l o r i d e + G e l a t i n - Go l d B o r a x T o n e r . . . . . . . . . . . . . . . . . . . . . 7 6

F i g u r e 6 - 8 A m m o n i u m C h l o r i d e + Ge l a t i n - G o l d T h i o c y a n a t e . . . . . . . . . . . . . . . . . . . 7 6

F i g u r e 6 - 9 A m m o n i u m C h l o r i d e + G e l a t i n - P l a t i n u m T o n e r . . . . . . . . . . . . . . . . . . . . . . . . 7 6

F i g u r e 6 - 1 0 A m m o n i u m Ch l o r i d e + Ge l a t i n

- Go l d B o r a x a n d

P l a t i n u m . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 6

F i g u r e 6 - 11 A m m o n i u m C h l o r i d e + G e l a t i n - Go l d A c e t a t e . . . . . . . . . . . . . . . . . . . . . . . . . . 7 6

F i g u r e 6 - 12 A m m o n i u m C h l o r i d e + G e l a t i n - P a l l a d i u m T o n e r . . . . . . . . . . . . . . . . . . . . . 7 6

F i g u r e 6 - 13 A l b u m e n N o T o n e r . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 6

F i g u r e 6 - 14 A l b u m e n Go l d B o r a x T o n e d . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 7

F i g u r e 6 - 15 A l b u m e n P l a t i n u m T o n e d . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 7

F i g u r e 6 - 16 A l b u m e n P a l l a d i u m T o n e d . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 7

F i g u r e 6 - 17 A l b u m e n Go l d A c e t a t e T o n e r . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 7

v

F i g u r e 6 - 18 A l b u m e n Go l d T h i o c y a n a t e T o n e r . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 7

F i g u r e 6 - 19 A l b u m e n Go l d B o r a x a n d P l a t i n u m T o n e d . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 7

F i g u r e 6 - 20 A l b u m e n Go l d T h i o c y a n a t e a n d P l a t i n u m T o n e d . . . . . . . . . . . . . . . . . . . . . . . 7 7

F i g u r e 6 - 21 H e a t T o n e d H i g h M a g n i f i c a t i o n . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 9

F i g u r e 6 - 22 H e a t T o n e d . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 0

F i g u r e 6 - 23 R e s u l t o f H e a t T o n i n g . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 0

C h a r t 4 - 1 F i l m D e n s i t y R e a d i n g s . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 1

C h a r t 4 - 2 F i l m P r i n t C o m p a r i s o n . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 2

C h a r t 4 - 3 F i l m T r a n s m i s s i o n . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 8

C h a r t 5 - 1 S i l v e r C h l o r i d e S e n s i t i v i t y . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 2

C h a r t 5 - 2 C u t - o f f F i l t e r s . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 2

C h a r t 5 - 3 F i l m T r a n s m i s s i o n . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 4

C h a r t 5 - 4 U V T u b e W a v e l e n g h t s . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 6

C h a r t 6 - 1 A l b u m e n T o n i n g . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 8

C h a r t 6 - 2 S o d i u m C h l o r i d e T o n i n g . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 8

C h a r t 6 - 3 A m m o n i u m C h l o r i d e a n d G e l a t i n . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 8

L I S T O F C H A R T S

T a b l e 1 - 1 C h l o r i d e s a n d A d d i t i v e s . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 8

T a b l e 1 - 2 O t h e r c h l o r i d e s . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 1

T a b l e 1 - 3 B i n d e r s . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 3

T a b l e 2 - 1 P a p e r C o l o u r s . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 5

T a b l e 4 - 1 F i l m D e n s i t y R e a d i n g s . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 0

T a b l e 5 - 1 E x p o s u r e T o m e s . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 5

T a b l e 6 - 1 H e a t T o n i n g . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 0

L I S T O F T A B L E S

vi

vi i

A C K N O W L E D GE M E N T S

Th e au th or wi sh es to th an k th e fol l o wi n g pe opl e wh o gave

en or mo u s con ti n u al su pp or t du r i n g th i s pr oject.

A ssoci ate Pr ofe ssor Gal e S pr i n g : R M IT A ppl i ed S ci en ce

(Ph otogr aph y)

Ph r ed Peter se n : R M IT A ppl i ed S ci en ce (Ph otogr aph y)

A l an E l l i ott : Con su l ti n g ch emi st.

D r S tu ar t Hen der son : Ul tr aviol et R adi ati on S ecti on of

A R PA NS A.

D r Joh n Javor n i cz ky: Ul tr av i ol et R adi ati on S ecti on of

A R PA NS A.

D r M i ch ael War e : Con su l ti n g ch emi st

Ph i l l i p Fr an c i s: M an ager , R M IT M i cr oscop y & M i cr oan al ys i s

Faci l i ty A ppl i ed Ph ysi cs

James R ei l l y : D i r ector , Image Per man en ce In sti tu te R och e ster

In sti tu te of Tech n ol ogy R och e ste r , NY

Pr ofessor M al col m M cC or mack : R M IT Un i ver si ty

Tr i sh an d War r en S i mpson : S i mpson Gr aph i cs

L oth ar Hu ber : B on d Imagi n g , R i chmon d

D an i el l e E dwar ds : A u sti n R epatr i ati on Hospi tal , Hei del ber g

M i ch ael Gr ey : For mer Cu r ator of Ph otog r aph y at th e Fox Tal b ot

M u seu m UK . (Gr ey i n tr odu ced th e sal t pr i n t to th e au th or in

1 9 99 )

vi i i

MECHANISMS OF CONTR OL LING COL OUR AND AEST HETIC

APPEARANCE OF THE PHOTOGR APHIC SALT PRINT

A B S T R A C T

Th e sal t pr i n t i s an i mp or tan t pa r t of ph oto gr aph y , both i n i t s

h i stor i c val u e an d i n th e t on al r an ge i t can pr ovi de. Th i s ton al

r an ge i s gr eater th an an y oth er ph otogr aph i c pr i n ti n g pr oc ess

avai l abl e to date attr i bu ted to th e i n h er en t mas ki n g abi l i ty of

th e metal l i c si l ver . Ho wever t h e i n tr i n si c pr odu cti on pr obl e ms

h ave made i t a „for gotten ‟ p r ocess. Th e r e ar e fi ve key

pr obl ems .

1 . Th e di ffi cu l ti es i n ach i evi n g t h e poten ti al ex ten si ve

ton al r an ge .

2 . Th e var yi n g col ou r of th e pr i n t .

3 . S tai n i n g th at appear s i n th e p r i n t, du r i n g an d after

pr ocessi n g.

4 . In stabi l i ty an d l on gevi ty o f th e s al t pr i n t .

5 . Con tr adi ctor y an d i n accu r ate i n for mati on i n m ater i al

pu bl i sh ed on th e sal t pr i n t.

A l th ou gh t h e emph asi s o f th e r esear ch i s on ex pl or i n g an d

con tr ol l i n g th e col ou r an d ton al r an ge , th e stai n i n g pr obl ems

an d stabi l i ty of th e pr i n t ar e a l so addr essed .

Th e mater i al s u se d for con t act n egati ves to day var y i n b oth

captu r e an d ou tpu t, f r om an al ogu e fi l m pr oces sed i n th e

tr adi ti on al wet dar kr o om to a var i ety of tr an spar en t fi l m

pr i n ted fr om di gi tal fi l e s . In ade qu ate den si t y an d ton al r an ge

can affect a l l type s of n egat i ves . To pr ovi de su ffi ci en t

ex posu r e ti me for th e sal t p r i n ts ex ten ded ton al r an ge

adju stm en ts to th e n egati ve wer e n ecessar y . L on g ex posu r es

ar e n ecessar y to con ver t su ffi ci en t si l ver sal ts to th e i mage

1

maki n g me tal l i c si l ver . Th i s m ax i mi ses th e i n tr i n si c s el f -

maski n g pr oce ss .

Ul ti matel y th i s r esear ch h as u n c over ed ways t o con tr ol col ou r

an d ton al r an ge an d cer tai n aesth eti c qu al i ti es of th e sal t

pr i n t , wh i l e si mu l tan eou sl y r esol vi n g some of th e con fl i cts i n

pu bl i sh ed i n for mati o n . A ccu r ate an d c on si sten t me th ods of

pr ocessi n g el i mi n ate stai n i n g , pr ovi di n g s ome stabi l i ty to th e

pr i n t . Th e acti vi ti e s an d step s ca r r i ed ou t to make a sal t pr i n t

ar e man u al ; pr eci se du pl i cati on i s th er efor e al most

u n attai n abl e. Never th el ess, a l th ou gh test s on a den si t ome ter

may di spl ay n u m er i c di ffer en ces , vi su al di ffer en ces ar e bar el y

n oti ceabl e.

2

I N T R O D U C T IO N

Th e sal t pr i n t wa s di sco ver ed i n 1 83 3 by Wi l l i am Hen r y Fox

Tal bot (1 8 0 7 – 1 87 7 ). Th i s two- step pr oce ss for m s l i gh t

sen si ti ve pap er . Fi r st, th e paper i s coated wi th a sal t sol u ti on .

Th en , si l ver n i tr ate sol u ti on sen si ti ses th e pap er by cr eati n g

si l ver ch l or i de. E x posu r e to l i gh t ch an ges th e si l ver ch l or i de

to i mage ma ki n g me tal l i c si l ver . Th i s s ame pr oces s occu r s i n

al bu men pr i n ti n g. A l bu men pr i n ti n g h ad an en or mou s i mpact

for an ex ten si ve per i od of ti me i n th e 1 9 t h cen tu r y. It i s o ften

tr eated as a di ffer en t pr oce ss bu t essen ti al l y i t i s a sal te d

paper pr i n t wi th an al bu m en bi n der . Th i s was th e r ati on al e f or

i n cl u di n g th e al bu men pr i n t i n th i s r esear ch . A l bu men i s

n or mal l y made fr om th e wh i t e of h en ‟ s eggs.

A l th ou gh th e sal t pr i n t i s q u i te si mpl y t wo ch e mi cal s

combi n ed on paper to ma ke th e l i gh t sen si ti ve si l ver ch l or i de,

i t i s fr au gh t wi th pr obl em s. Th es e pr obl ems can i n ter fer e wi th

th e appear a n ce an d th e stabi l i ty of th e sal t pr i n t. Wi th few

ex cepti on s mos t pr i n ted tex ts t oday pa y l i ttl e r egar d to th e

compl ex i ti e s of th e pr oc ess an d th e i n tr i n si c pr obl em s. S al t

pr i n ts can pr ovi de a wi d e r an ge of col ou r s an d ton e s. Ho wever

th ese c ol ou r s can be d i ffi cu l t to pr edi ct or c on tr ol . It i s

th er efor e n ecessar y to u n der st an d h ow di ffer en t ch emi cal

sol u ti on s an d var i ou s pr oces ses an d meth ods i n fl u en ce th e

ou tcom e of th e pr i n t. Th e sal t pr i n t h as an ex tr aor di n ar y ton al

r an ge wh i ch i s n ot ach i evabl e i n an y ot h er ph otogr aph i c pr i n t

pr ocess. Th i s t on al r an ge can on ly be gai n ed by n egati ves wi th

speci fi c qu al i ti es th at can u ti l i se th e u n i qu e sel f - mas ki n g

abi l i ty of pr i n ti n g -ou t si l ver ch l or i de.

A IM A ND S COPE

Th e ai m of th i s stu dy i s t o ex p l or e an d de vel op meth od s of

con tr ol l i n g col ou r wh i l e over co mi n g man y of th e i n h er ent

pr obl ems i n th e pr oces si n g. B ec au se to th e en or mou s var i ety

of paper avai l abl e, tes ti n g for pr i n ti n g was n ar r o we d to

pr i mar i l y 1 0 0 % cotton paper s.

3

Th e n egati ve was cr i ti cal i n r eal i si n g th e fu l l p oten ti al o f th e

sal t pr i n ts ton al r an ge. Th e fi l m teste d was l i mi ted b y

avai l abi l i ty i n th e A u str al i an market. Th e r esear ch i n to var i ou s

fi l ms to cr eate di gi tal ou tpu t n e gati ves pr oved to be co mpl ex

an d ti me con su mi n g. It be came c l ear th at an i n -dep th stu d y i n

th i s ar ea wou l d di st or t th e bal an ce of th i s th esi s. Th er efor e

on l y a sel ecte d n u mber of fi l m ou tpu t type s wer e ex ami n e d.

D i gi tal captu r e wa s n ot i n cl u de d du e to th e c ompl ex ch an gi n g

mar ket pl ace of di gi tal camer as.

For mu l as, addi ti ves an d bi n der s ar e an al ysed i n th e fi r st

ch apter ex ami n i n g h ow th e y affec t th e col ou r , ton al r an ge an d

aesth eti c app ear an ce of th e sal t pr i n t. B oth th e L *a. b. col ou r

syste m an d Pan ton e® col ou r ch arts i den ti fy an d as si st wi th

col ou r compar i s on s.

Th e n eed to u n der stan d p aper c ompo si ti on an d pr odu c ti on i s

h i gh l i gh ted, ex pl ai n i n g wh i ch t ypes to u se an d th e col ou r

di ffer en ces th ey mak e i n sal t pr i n ti n g. D i ffer en t meth ods an d

th e pr obl em s fa ced wh en ap pl yi n g for mu l as to th e pap er s ar e

ex ami n ed.

Compl ex i ti es an d ob stacl es i n fi n di n g su i tabl e n egati v e fi l m

mater i al s ar e di scu sse d, i n cl u di n g th e var i ou s for ms an d h o w

each of th ese affects th e ou tco m e of th e sal t pr i n t. Th e effects

th at u l tr a vi ol et (UV ) an d var i ous wa vel en gth s of vi si bl e l i gh t

h ave on th e pr i n t ar e ex ami n ed i n cl u di n g th e effec ts o f

ex posu r e ti me, i n ten si t y, h eat a n d h u mi di ty du r i n g ex posu r e.

A n i n vesti gati on of th e effects of pr ocessi n g of th e pr i n t was

car r i ed ou t. Th i s i s wh er e hi stor i cal an d con temp or ar y

pr acti ces ar e compar ed, an al y sed an d acces sed. Th i s i s

fol l o wed by an over vi e w, i d e n ti fyi n g pr obl em s an d th ei r

sol u ti on s. Th e eval u ati on s an d dedu cti on s of th e pr evi ou s

ch apter s ar e pu l l ed toge th er fo r a di scu s si on an d th e fi n al

con cl u si on s .

T h e Sa l t P r i n t Ma n ua l copy i s pr o vi ded i n A ttach men t 2 of th i s

th esi s. Th i s i s th e ou tcome of t h i s r esear ch , compr essed an d

4

si mpl i fi ed i n to th e for m of a pr acti cal u ser s gu i de. A bou n d

pu bl i cati on i s sch e du l ed for pr i n ti n g by ffotof fi l m p u b l i sh i n g ,

B r i gh ton , UK after th e assessmen t of th i s paper .

A CD pr ovi des a n i l l u str ati ve compar i son of sal t pr i n ts

ton al i ty an d c ol ou r var i ati on s i n A ttach men t 1 . Th e ph y si cal

ex h i bi ti on of th e wor k wa s o pen ed on 2 7 t h Feb 2 0 0 8 at

Ph otoS pace, 3 4 D i gh t S t. Col l i n gwood 3 0 6 6 .

5

B A C K GR O U N D

S i n ce A r i stotl e (3 8 4 -3 22 B C) (E der , 1 9 78 ) th er e i s evi den ce th at

men an d wom en h ave been ex pl o r i n g th e r el ati on sh i p between

l i gh t an d ch emi cal s . It wa s n ot u n ti l 1 8 34 th at Wi l l i am Hen r y

Fox Tal bot‟ s i n qu i r i n g mi n d l ed h i m t o th e mom en tou s

di scover y of per man en t ch emi ca l l y pr odu ced i mages cr eated

by l i gh t. Hi s sal ted paper pr i n ts wer e th e fi r st ph ot ogr aph i c

n egati ve -to -po si ti ve si l ver pr o cess. Tal b ot‟ s „ph otog en i c

dr awi n gs‟ an d h i s con ti n u al di sc over i es h ad a pr ofou n d effect

on both ph otogr aph y an d th e dev el opmen t of pr i n tmaki n g.

Wi l l i am Hen r y Fox Tal bot (1 8 0 0 -1 8 70 ) was an u pp er cl as s wel l

edu cated gen tl e man wi th a br i l li an t mi n d. A s ear l y as 1 84 2

Tal bot pr opo sed th e tel e ph oto l e n s, el ectr on i c fl ash , i n fr ar ed

ph otogr aph y an d ph ot oty pe setti n g, th u s setti n g th e

fou n dati on of ph otogr avu r e. Tal bot pr edi cted th e fu tu r e of

ph otogr aph y wou l d f ol l o w th e way of th e pr i n ti n g pr ess

(S ch aaf, 1 9 96 ) . Of Tal bot‟ s for ty - two pu bl i sh ed paper s, th i r ty -

two deal t wi th l i gh t, de mon s tr ati n g th e ob ses si on h e h ad wi th

th e po wer of l i gh t (Gr ay et al . , 20 0 2 ) . Th i s ou tstan di n g

sch ol ar , ex per i men ter , th i n k er an d ar ti st, was desti n e d to

become on e of th e m ost i n fl u en ti al sci en ti st s of th e

n i n eteen th cen tu r y. For tu n atel y for h i stor i an s an d

ph otogr aph i c r esear ch er s h e docu men ted m ost of h i s

ex per i men ts (S ch aaf, 2 0 0 0 ) . Fr om th e wor l d of sci en ce Tal b ot

cr eated a n e w cr aft an d ar t for m. He came i n to ph otogr aph y a s

a „pi ctu r e mak er r ath er th an a sci en ti st‟ (Wal l s an d A ttr i dge,

1 9 77 ) .

Tal bot di sc over ed th e r ati o bet we en sal t an d si l ver n i tr ate

r equ i r ed to cr eate , an d th en „stab i l i z e ‟ an i mage. In 1 8 39 wi th

th e assi stan ce of h i s col l eagu e S i r Wi l l i am Her sch el ( 1 79 2 –

1 8 71 ), h e was abl e to „fi x ‟ th i s i mage per man en tl y on paper .

D espi te th i s, i mage fadi n g th r ou g h i n adequ ate pr ocessi n g ,

cau se d Tal bo t a gr eat deal of gr i ef.

Th e ph oto gr ams, or a s Tal b o t cal l ed th e m „ph ot ogen i c

dr awi n gs ‟ , wer e cr eated by coati n g wr i ti n g paper wi th a sal t

6

(sodi u m ch l or i de) sol u ti on , to wh i ch after dr yi n g, h e appl i ed a

coati n g of s i l ver n i tr ate sol u ti on . A n object su ch as a l eaf or

l ace wa s pl aced on th e dr y, n ow l i gh t sen si ti ve paper . Tal bot

ex posed th i s to th e su n to cr ea te a n egati ve i mage. Th i s i s

wh at i s cal l ed a sal t pr i n t or sa l ted pap er pr i n t. In 1 8 3 4 h e

began ex posi n g i mage s i n a cam er a. Tal bot pr odu ce d p osi ti ve

i mages by c on tact pr i n ti n g th ese sal t pr i n t n egati ves.

In 1 84 0 h e di scover ed th at Gal l ic aci d d evel op ed ou t a l aten t

i mage on pap er . Th i s cr eated th e fi r st devel ope d -ou t n e gati ve -

to-p osi ti ve ph o togr aph i c pr i n t pr oce ss an d so dr a mati cal l y

decr eased th e ex p osu r e ti me i n th e camer a fr om h ou r s to

secon d s (S ch aaf, 2 0 0 0 ) . Th e effect on ph otogr aph y‟ s

r epr odu cti ve po wer wa s en or mou s.

S al t pr i n ti n g i n cl u des th e al bumen pr i n ti n g pr ocess. B oth

r equ i r e si l ver ch l or i de as th e fou n dati on to for m an i mage.

Th e Fr en ch ph otogr aph er L ou i s D ési r é B l an qu ar t -E vr ar d ( 1 80 2 -

1 8 72 ) devel ope d th e al bu men pr i n t i n th e l ate 1 8 4 0 s. He

di scover ed th e al bu men pa per wh i l e sear ch i n g f or

i mpr ovemen t s i n Tal bot‟ s cal o ty pe (pap er n egati ve) pr oces s.

B l an qu ar t -E vr ar d pr esen ted h i s di scover y to th e Fr en ch

A cademy on M ay 2 7 , 1 8 50 . By 1 8 5 5 most ph otogr aph er s

ch an ged to al bu men pr i n ti n g. Th i s r emai n ed th e pr i n ci pal

pr i n ti n g meth od u n ti l 1 8 9 5 . Ex per i men ts on a l bu men wi th ou t

sal t h ad be en car r i ed ou t i n 1 8 3 9 by Tal b ot an d R ober t Hu n t i n

1 8 41 . Th e i mage was n ot mad e fr om si l ver ch l or i de bu t si l ver

al bu mi n ates , wh i ch al so r edu ce s to met al l i c si l ver (R ei l l y,

1 9 80 ) .

„A l ter n ati ve ‟ i s a ter m u sed f or ear l y ph ot ogr aph i c pr i n t

pr ocess es. S al t pr i n ti n g i s co n si der ed th e fi r st of th e se

pr ocess es . Nu mer ou s pr o ce sse s fol l o wed, su ch as cyan o type,

gu m bi ch r omates, pl ati n u m/ pal l a di u m an d van dyke br o wn .

P H O T O G R A P H I C P R I N T P R O C E S S E S .

Th e maj or categor i es i n wh i ch ph otogr aph i c pr i n t pr oce sse s

fal l ar e „devel ope d -ou t‟ an d „pr i n ted -ou t‟ .

7

D evel oped -ou t, al so kn o wn a s p r ocesse d -ou t, r efer s t o m ost

ph otogr aph i c pap er s wh er e th e i mage i s ca ptu r ed bu t can n ot

be seen u n ti l ch emi cal bath s „de vel op‟ or „ pr o cess‟ th e l at en t

i mage. D escr i bed as th e ch emi c al r edu cti on of si l ver par ti cl es ,

i t i s car r i ed ou t i n th e dar kr o om u n der a r ed sa fe l i gh t .

Pr ocessi n g - ou t h as been th e most com mon pr acti ce of pr i n ti n g

fr om 1 9 0 5 (R ei l l y, 1 9 80 ) u n ti l r ecen tl y wh en di gi tal ou tpu t

su r passed tr adi ti on al wet pr oces s es.

Pr i n ti n g -ou t r efer s to th e pr oce s s es wh er e pr i n ts ar e cr eate d

by l i gh t en er gy on l y. Th e r e ar e n o ch e mi cal ai d s u se d t o

pr odu ce th e i mage. 1 9 t h cen tu r y ph otogr aph i c pr i n t pr oces ses

wer e car r i ed ou t by a pr ocedu r e kn o wn as con tac t pr i n ti n g.

Th e n egati ve i s th e same si z e as th e fi n a l pri n t an d the

n egati ve i s i n „ c on tact ‟ wi th t h e l i gh t sen si ti z ed paper . A

posi ti ve i mag e i s cr eated wh en e x posed to th e u l tr avi ol et an d

vi si bl e l i gh t spectr u m. Th e pr i n t can be vi e wed du r i n g th e

ex posu r e. A h i n ged back pr i n tin g fr ame al l ows ac cess t o ch eck

th e ex p osu r e du r i n g pr i n ti n g. For th e fi r st si x t y -fi ve year s of

ph otogr aph y th i s was th e meth od of cr eati n g ph otogr aph i c

pr i n ts (R ei l l y, 1 98 0 ) .

P R I N T T O N E

A sal t pr i n t i s mon och r omati c; h owever fr om th e ver y ear l y

yea r s of ph otogr aph y th e var yi n g ton al di ffer en ces h ave been

di scu ss ed . In th e i n tr odu cti on t o T h e P en c i l of Na tur e , 1 844

Tal bot d efen ds th e di ffer i n g col o u r s by s tat i n g “ th er e i s s ome

var i ety i n th e ti n ts th ey pr esen t” an d ar gu es th at th e i mages

su i t th e col ou r s. (S ch aaf, 2 0 0 0 ) S ch aaf su ggest s th at T al bot

may h ave been r el u ctan t t o u se „ fi x er ‟ du e to th e „u n pl easi n g‟

col ou r i t cr eated. Th er e i s di sc u ssi on abou t th e con tr ol of

col ou r bu t i n man y case s th e r ea son s f or th e col ou r var i ati on s

ar e n ot ex pl i cated .

Th e con tr ol of col ou r an d aest h eti c appear an ce of th e sal t

pr i n t r equ i r e d an i n -depth ex pl or ati on of th e ch emi cal an d

mech an i cal pr oces s es car r i ed o u t i n pr odu cti on . Th e h i gh

pr opor ti on of con fl i cti n g i n for m ati on fou n d on pr o cess es an d

8

th e for mu l as i n h i stor i c an d con tempor ar y pu bl i cati on s i s of

con cer n . R ecom men dati on s on fi x i n g th e sa l t pr i n t wer e a case

i n poi n t. Th ey r an ge d fr om 1 0 mi n u tes i n a 1 0 % sodi u m

th i osu l ph ate bath (Cr a wfor d, 1 9 7 9 ) to th e oth er ex tr eme of

two bath s wi th 3 0 secon ds i n e ach bath of 1 0 % sodi u m

th i osu l ph ate (Ja mes, 2 0 0 2 ) . A l thou gh th ese ar e th e ex tr eme s,

n ot on e of th e fol l o wi n g pu bl i ca ti on s con cu r : (B ar n i er , 2 00 0,

Far ber , 1 9 98 , R ei l l y, 1 98 0 , Webb an d R ee d, 2 0 0 0 ) . S i mi l ar

i n stan ces th r ou gh ou t th e meth ods an d f or mu l a s i n th es e

pu bl i cati on s en cou r age i n vesti gat i on .

S can n i n g E l ectr on M i cr oscope s h ave been u sed as a n on -

destr u cti ve me th od to an al yse h eavy metal s wh en

i n vesti gat i n g th e stabi l i ty of or i gi n al 1 9 t h cen tu r y sal t pr i n ts

(War e, 2 0 0 3 ) . Th e si l ver par ti cl es si z e s ar e di scu s sed i n

r el ati on sh i p to th e fr agi l e n atu r e of th e pr i n t . Th i s si l ver i s

vu l n er abl e to i mpu r i ti es , both at mosph er i c an d i n tr i n si c tr ace

el emen ts . War e an d Jen kyn - Jon es ar gu e t h e col ou r of th e sal t

pr i n t var i es as a r el ati on sh i p to th e per cen tage of su l ph i de ,

affect i n g l on g -ter m stabi l i ty ( Wa r e, 2 00 3 Jen kyn -Jon e s, 1 9 8 8)

Th ey di scu ss th e col ou r i n h i stor i c pr i n ts bu t do n ot r efer to

con temp or ar y sal t pr i n ts .

T h e Al b u men a n d Sa l ted P a p er Book : T h e H i stor y a n d P ra c tic e

of P h otogr a p h ic Pr i n ti n g, 18 4 0 -18 9 5 (R ei l l y, 19 80 ) i s th e most

compr eh en si ve pr i n ted mat er i al avai l abl e on th e sal t an d

al bu men pr oce ss e s. R ei l l y de scr i bes th e h ea t ton i n g pr oces ses

an d th e col ou r di ffer en ces bet we en fal se u l tr avi ol et l i gh t an d

n atu r al su n l i gh t ex posu r es bu t fai l ed to ex pl ai n the

ph en omen a occu r r i n g wi th th e si l ver par ti cl es an d ch emi cal s ,

on an d i n th e paper .

A l th ou gh th e di scover y of th e sal t pr i n t i s ackn owl e dged as

th e bi r th of ph otogr aph i c r epr od u cti on , toda y i t h a s l i ttl e r eal

r el evan ce i n th e mai n str eam an d comm er ci al wo r l d of

ph otogr aph y. In fact i t i s on e o f th e l east kn o wn an d pr acti sed

of th e „al ter n ati ve pr oce sses‟ . S tr on g ar gu men ts for th i s

r esear ch der i ve fr om th e si gn i f i can t h i stor i c val u e an d i t s

9

con si der abl e t on al r an ge wh i ch i s sti l l con si der ed gr eater th an

th a t of al l oth er ph otogr aph i c pr i n ti n g pr ocesses t o date.

1 0

R E S E A R C H D E S IG N

Ways of c on tr ol l i n g col ou r an d th e aesth eti c ap pear an ce of th e

sal t pr i n t wer e par a mou n t t o th i s r esear ch . R es ol vi n g

i n con si sten ci e s i n cu r r en t an d h istor i cal pu bl i cati on s wa s al so

an i mpor tan t c omp on en t. B ackgr ou n d r esear ch pr ovi ded l i ttl e

i n for mati on on th e ch emi cal reacti on s or wh at ph y si cal l y

sti mu l ates ac ti vi ty wi th i n th e pr i n t to affect col ou r .

E x cepti on s wer e fou n d i n ( Jen kyn -Jon e s 1 9 8 8; R ei ll y 19 8 0 ) an d

(War e 1 9 9 4 ). Th ey each di scu s s t h e si l ver par ti cl e si z e an d i ts

r el ati on sh i p to l i gh t wh i ch may affect th e pr i n t col ou r . Th ese

aspect s wer e al so ex pl or ed.

Th e meth od of cr eati n g a sal t pr i n t h as di sti n ct steps. E ach of

th ese step s ar e al l ocated sep ar ate ch apter s. Th i s i sol at e s th e

var i ou s pr obl ems wi th i n each of th e steps . Th e r esu l ts of th e

r esear ch on each of th ese steps a r e dr awn togeth er i n th e fi n al

di scu ssi on to for m th e fi n al con c l u si on .

Th e qu esti on s th i s r esear ch wa s desi gn ed to an s wer ar e as

fol l o ws:

1 . Wh at ar e th e con tr i bu ti n g factor s th at cau se th e col ou r

di ffer en ces i n th e sal t pr i n t?

2 . Can th e col ou r an d vi su al aspects of th e sal t pr i n t be

pr edi cted an d con tr ol l ed ?

3 . Can col ou r s u sed i n th e spec tr al n egati ve offer th e same

con tr ol i n con tr ast, col ou r an d to n al r an ges as tr adi ti on al

an al ogu e fi l m?

4 . D o con temp or ar y meth od s of pr o cessi n g offer pr ote cti on for

l on gevi ty of th e sal t pr i n t?

1 1

Th e i n vesti gati on wi l l i n cl u de:

1 . Iden ti fy i n g th e r el ati on sh i p bet ween th e col ou r of th e pr i n t

an d for mu l as, bi n der s an d paper s .

2 . A n a ttempt to d et er mi n e th e r el ati on sh i p bet ween col ou r

an d th e si z e of th e si l ver par ti cl es.

3 . R efi n i n g for mu l as an d meth ods.

P R O J E C T M E T H O D O L O G Y

S al t pr i n t tests wer e pr odu ced i n a con tr ol l ed en vi r on men t

u si n g var i ou s for mu l as , paper s, n egati ve typ e s an d meth o ds.

M E T H O D S

for both con temp or ar y an d 1 . R esear ch pr i n ted mater i al

h i stor i c sal t pr i n t for mu l a s, r evi ew an d te st di ffer en ce s.

2 . Test di ffer en t sol u ti on r ati o s o f sal t to si l ver u si n g s tep

we dges t o eval u ate col ou r an d to n al di ffer en ces .

3 . Fi n d a r el i abl e meth od of coa ti n g paper th at pr ovi des

con si sten c y an d accu r acy i n appl yi n g sol u ti on s .

4 . R ecor d th e pr i n t col ou r wi th Pan ton e® an d L *a . b. col ou r

syste ms f or con si sten t r efer en ce poi n t s.

5 . E x pl or e d i ffer en t water -s ol u bl e ch l or i des for ch an ge s i n

col ou r , n oti n g possi bl e effe cts on th e l on gevi ty of th e pr i n t.

6 . E x ami n e h o w di ffer en t pa per s aff ect th e ton al r an ge, c ol ou r

an d l on gevi ty.

1 2

7 . E stabl i sh a con tr ol n egati ve. Comp ar e var i ou s n egati ve

type s, i n cl u di n g spectr al n egati ves to fi n d wh i ch pr ovi des

th e g r eatest ton al r an ge.

8 . E val u ate th e r espon se of si l ve r ch l or i de i n th e var i ou s

spectr u m s of UV tu bes an d su n l i gh t s an d effect on col ou r

an d con tr ast.

9 . Fi n d th e peak sen si ti vi ty of si l ver ch l or i de i n both u l tr a

vi ol et an d vi si bl e l i gh t spectr u m s .

1 0 . In vesti gate ton i n g; co mpar e ch em i cal an d h eat meth od s of

ton i n g . A n al yse col ou r , possi bl e ch an ges i n th e paper an d

si l ver par ti cl es.

1 1 . R evi ew meth od s of pr oce ssi n g pr i n t s an d th e effect s on

th e l on gevi ty an d col ou r .

FE I Nova Nan oS E M was u sed to i n vesti gate an d r esol ve man y of

th e r esear ch qu esti on s . Th i s en v i r on men tal scan n i n g el ectr on

mi cr osco pe i s h ou sed i n th e Ph ysi cs de par tmen t at R M IT. It

pr ovi d ed a ph y si cal vi e w of th e s i l ver par ti cl es. A n E DA X X -r ay

detector attach e d to th e Nan o S E M r eveal ed tr ace el emen ts

pr esen t i n th e sal t pr in t paper , ho wever th er e wer e di ffi cu l ti es

du e to th e paper co mpo si ti on of t h e test sam pl e s.

Th e dete ctor for (E D X) an al y si s d i d n ot ca ptu r e u sabl e i mages;

bu t by empl oyi n g th e TL D an d E D X detec tor s both i magi n g an d

data cou l d be gat h er ed. Hi gh el ectr on en er gy mean t a pr obabl e

cr ystal cou l d be i den ti fi ed at abou t 1 3 0 , 0 00 ti mes

magn i fi cati on , on ce focu se d i t was magn i fyi n g u p to th e

max i mu m of 3 0 0 , 00 0 ti mes wh er e th e cr ystal fi l l ed th e l en s. It

wa s at th i s poi n t th at th e E D X r eadi n gs wer e taken as fe w

oth er el emen ts cou l d di stor t th e r eadi n g.

1 3

Th e atomi c wei gh t p er cen tage wa s gath er ed f or si l ver an d

su l ph u r i n al l sampl es. A n y u n u su al l y l ar ge peaks i n th e E D X

r eadi n gs cr eated by tr ace el e men ts wer e i n ves ti gated for

possi bl e r el evan ce.

D r Joh n Javor n i cz ky of th e Ul t r avi ol et R adi ati on S ecti on of

A R PA NS A u sed a CA R Y 5 0 spectr o ph otom eter to assi st wi th th e

gath er i n g of spectr al tr an smi ssi on data of fi l m r equ i r ed for

th i s r esear ch . Th i s i n cl u ded th e spectr al emi s si on r eadi n gs

fr om th e u l tr avi ol et fl or escen t tu bes.

1 4

C h a p t e r 1 T H E F O R M U L A S

Tests wer e car r i ed ou t on a n u mber of di ffer en t combi n ati on s

of for mu l as to stu dy th e effec t on th e col ou r , th e ton al r an ge

an d th e aesth eti c appear an ce of th e sal t pr i n t . E ar l y an d

cu r r en t for mu l as wer e ev al u ate d wi th th e best ou tc ome of

each di scu ss ed.

Tal bot u se d s odi u m ch l or i de i n h i s fi r st sal te d pa per pr i n ts.

S odi u m ch l or i de i s co mm on tabl e sal t . T oday mo st tabl e sal t s

con tai n addi ti ve s, (s odi u m al u m i n osi l i cate ) an ti -ca ki n g agen t

to st op m oi stu r e abs or p ti on a n d may be i odi z ed ( sodi u m

i odi de). Tes t s fou n d th ese addi ti ves r eact ed wi th th e si l ver

n i tr ate cr eati n g a ch emi cal fog . Th i s r edu c ed th e pr i n t qu al i ty

by degr adi n g th e wh i te i n th e h i gh l i gh t ar eas . A s a r esu l t al l

ch l or i des wer e pu r ch ased th r ou gh ch e mi cal su ppl i er s. Th e

col ou r s of step wedge s pr i n ted on th i s paper wi l l n ot pr ovi de

an accu r ate r epr esen tati on bu t wi l l cl ear l y i n di cate r el evan t

di ffer en ces. A col ou r an al y si s pr ovi ded wi th both Pan t on e®

an d L *a. b. c ol ou r s f or sh ado w an d mi d -ton e s (i n di cat ed b y th e

wh i te poi n ter s) wi l l al l o w th e r ea der to ch e ck th e col ou r s on a

compu ter scr een or c on su l t a Pan ton e® col ou r ch ar t i f

accu r acy i s desi r ed. A l l F or mu l as ar e set ou t i n A ppen di x 1 .

Th e fol l o wi n g i n for m ati on su m mar i ses th e r esu l ts o f th e

test ed sol u ti on s. Th e fi r st t wo s ol u ti on s wer e th e base f or th e

addi ti ves of sodi u m ci tr ate an d p otassi u m di ch r omate.

o S ol u ti on s: S odi u m Ch l or i de 2 % , si l ver n i tr ate 12 % (NaCl

12%) 2% + AgNO 3

o S ol u ti on s: A mmon i u m Ch l or i de 2 % , si l ver n i tr ate 12 %

12%) (NH 4 Cl 2% +AgNO 3

Wh en com par i n g th e pr evi ou s s ol u ti on s a m mon i u m ch l or i de

wi l l sl i gh tl y decr ea se ex p osu r e ti me an d th er ef or e th e c on tr ast

of th e pr i n t. S odi u m ch l or i de i s sl i gh tl y war m er i n col ou r as

seen i n Fi gu r es 1 -1 an d 1 -2 .

1 5

S O D I U M C I T R A T E

S odi u m ci tr ate i n cr eases th e r ed u cti on of th e si l ver ch l or i de

an d si l ver ci tr ate to me tal l i c si l v er on ex posu r e to l i gh t. Th i s

decr eases ex p osu r e ti me an d th e r efor e decr eases th e con tr as t.

Con tr ar y to t ex t su gge sti n g s odi u m ci tr ate war ms th e col ou r

r esu l ts of test s f ou n d th at i t c oo l s th e col ou r sl i gh tl y . Th e

ton al r an ge i s ex ten ded gi vi n g mor e br i l l i an ce by se par ati n g

th e ton es . In cr easi n g th e sodi u m ci tr ate per cen tage co ol e d th e

col ou r s fu r th er . Fi gu r es 1 -3 an d 1 -4 sh o w th e di ffer en ce

bet ween s odi u m ch l or i de wi th s odi u m ci tr ate an d A mmon i u m

ch l or i de wi th s odi u m ci tr ate.

3

3

o S ol u ti on s: S odi u m Ch l or i de 2 % + si l ver ni tr ate 12 % + 12%+ Na 2%) sodi u m ci tr ate . 2 % (NaCl 2% + AgNO C 6 H 5 O 7

3

12% +Na 2%) o S ol u ti on : A mmon i u m Ch l or i de 2 % + si l ver n i tr ate 1 2 % + Cl 2% +AgNO 3 sodi u m ci tr ate . 2 % (NH 4 O 7 H 5 C 6

P O T A S S I U M D I C H R O M A T E

2 dr ops of potassi u m di ch r oma te ( 5 % sol u ti on ) in 30 ml of the sal t sol u ti on : (R ei l l y, 1 9 80 )

o In cr ease d th e con tr ast of th e i ma ge . Fi gu r e s 1 -5 an d1 -6 i l l u str ate s th e ton e l oss i n th e h i gh l i gh ts .

o In cr ease d th e ex posu r e ti me an d sl i gh tl y war med th e ton es.

Wh en 2 dr ops of a 1 0 % potas si u m di ch r omat e s ol u ti on wer e

u sed th er e was l os s of i n for mati on i n th e sh ado ws b efor e th e

ex posu r e cou l d r en der de tai l s i n th e h i gh l i gh ts. A n ammon i u m

ch l or i de sol u ti on wi th pota ssi u m di ch r omate i s 8 % to 1 0%

cool er i n col ou r th an sodi u m ch l or i de wi th p otas si u m

di ch r omate . (Th ese col ou r di ffer en ces wer e cal cu l ated fr o m

den si to meter r eadi n gs) Th i s i s i l l u str ated Fi gu r e 1 -5 an d

Fi gu r e 1 -6 .

V ar yi n g th e amou n t of pot assi u m di ch r oma te al l o wed c on tr ol

over th e con tr ast . Potas si u m di ch r omate i s on l y l i gh t -sen si ti ve

wh en i t h as s ometh i n g to ox i di se l i ke gel ati n .

1 6

D r War e offer ed th e fol l owi n g ex pl an ati on of h o w di ch r oma te

possi bl y affect s c on tr ast by em ai l on th e 2 9 t h of N ovem ber

2 0 07 . Potassi u m di ch r omate wi th si l ver n i tr ate for m s

i n sol u bl e si l ver ch r omate , th e C r (V I) can n ot ox i di se A g+ an y

fu r th er . Cr (V I) can h owever , ox i di se si l ver metal , A g, to A g+ . It

cu ts off th e h i gh er val u es i n th e ton al s cal e , r edu ci n g

sen si ti vi ty an d i n cr eas i n g th e c o n tr ast. Th e ch r omi u m(V I) a s

di ch r omate i s „u sed u p‟ wh en th e pr i n t i s made by ox i di si n g

th e si l ver metal , an d i s i n er t wh e n r edu ced to ch r omi u m(III).

o S ol u ti on s: S odi u m Ch l or i de 2 % + si l ver ni tr ate 12 % +

Potassi u m D i ch r om at e: 2 dr op s of 5 % s ol u ti on i n 3 0 ml s

3

2

of sal t sol u ti on . ( NaCl 2 % + AgNO Cr ) 12 % + K 2 O 7

o S ol u ti on s: A mmon i u m Ch l or i de 2 % + si l ver n i tr ate 1 2 %

+ Potassi u m D i ch r omate : 2 dr o ps of 5 % sol u ti on i n 3 0 ml s

2

2

Cl 2 % + AgNO3 12 %+ K Cr ) of sal t sol u ti on . ( NH 4 O 7

Figure 1-1 Sodium Chloride + silver nitrate

Figure 1-2 Ammonium Chloride + silver nitrate

Figure 1-3 Sodium Chloride + silver nitrate + sodium citrate.

Figure 1-4 Ammonium Chloride + silver nitrate +sodium citrate

Figure 1-5 Sodium Chloride + silver nitrate + Potassium Dichromate

Figure 1-6 Ammonium Chloride + silver nitrate + Potassium Dichromate

1 7

L* a. b. S o di um Chl o r i de + si l ve r ni tr ate P anto ne ® S o l i d M att

S h ado ws 4 6 25 2 0 1 6 1 8

M i d-ton es 4 7 05 4 0 1 9 1 7

Ammo ni um Chl o r i de + si l v e r ni tr ate

S h ado ws B l ack m 1 2 1 0

M i d-ton es 7 5 30 5 0 5 1 2

S o di um Chl o r i de 2 % + si l v er ni tr ate 12 % + so di um c i tr ate

1 0 S h ado ws B l ack m 1 2

6 1 0 M i d-ton es 7 5 19 3 6

Ammo ni um Chl o r i de + si l v e r ni tr ate + so di um c i tr ate

1 0 S h a do ws B l ack m 1 2

6 1 3 M i d-ton es 7 5 31 3 8

S o di um Chl o r i de + si l ve r ni tr ate + Po tassi um Di c hr o mate

1 0 S h ado ws B l ack m 1 2

9 1 9 M i d-ton es 7 5 04 5 2

Ammo ni um Chl o r i de + si l v e r ni tr ate + P o tassi um Di c hr o mate

S h ado ws B l ack m 1 2 1 0

M i d-ton es 8 0 0 5 4 1 0 1 1

Table 1-1 Chlorides and Additives

V A R I A T I O N T O S A L T F O R M U L A S

S al t pr i n ts pr oved to be at th e ir best wh en th e ch l or i de (sal t)

con ten t i s appr ox i matel y 2 % an d th e si l ver sol u ti on i s 1 2 %.

Ch an gi n g th e r at i o of sal t to si l v er can be u sed to con tr ol th e

1 8

appear an ce an d th e col ou r of th e fi n al pr i n t. Th e sodi u m

ch l or i de sol u ti on was th e bas e fo r mu l a for th e fol l owi n g tes ts.

D E C R E A S E S A L T P E R C E N T A G E : Tal b ot di scover ed th at by de cr easi n g

th e sal t th er e wa s an i n cr eas e i n l i gh t sen si ti vi t y , (S ch aaf,

2 0 00 ) bu t decr easi n g th e ch l or i de sol u ti on bel o w 1 % ten ds t o

pr odu ce pr i n ts th at l ack br i l l i an ce an d den si t y. D ecr easi n g

th e sal t i n th e sol u ti on to:

o 0 . 2 % cau se d an i n cr ease i n con tr ast al l o wi n g

i n for mati on i n th e sh ado ws bu t l i ttl e i n th e h i gh l i gh ts

o 0 . 5 % cau se d a fu r th er i n cr ease i n con tr ast . It beca me

war m er i n col ou r an d l os t some d etai l i n th e h i gh l i gh ts .

o 1 % cau se d th e sal t sol u ti on to i n cr ease th e con tr ast an d

th e ton es bec a me war mer i n col o u r .

I N C R E A S E S A L T P E R C E N T A G E : Tal bot fou n d th at by i n cr easi n g th e

amou n t of sal t i n th e s ol u ti on t h e paper be came l ess l i gh t

sen si ti ve (th i s wa s h i s fi r st at tempt at stabi l i z i n g (fi x i n g)

i mages) (S ch aaf, 2 0 00 ) . E ffects of i n cr easi n g th e sal t i n th e

sol u ti on :

o 3 % cr eate d a sl i gh t decr ease i n con tr ast an d th e ton e s

wer e cool er . Th i s per cen tag e p r ovi ded an ac ceptabl e

ton al r an ge, al l owi n g con tr ol ove r con tr ast.

i n con tr ast an d th e i mage o 5 % cr eated a decr ease

appear ed fl at.

o 1 0 % cr eate d a su bstan ti al de cr ease i n th e con tr ast ,

r esu l ti n g i n a fl at we ak pr i n t th at r etai n ed a pu r pl e pi n k

col ou r .

Th e step we dges i n Fi gu r e 1 -7 i n di cate th e effect di ffer en t

per cen tages of s odi u m ch l or i de h ave on th e ton al r an ge an d

col ou r s. Th ey r an ge fr om 0 . 2 % to 1 0 % of sodi u m ch l or i de

con secu ti vel y . A l l wer e ex pose d u si n g a 1 2 % si l ver n i tr ate

sol u ti on .

1 9

Figure 1-7 Silver chloride % differences

O T H E R C H L O R I D E S

A l an E l l i ott su ggested by emai l 1 0 t h A pr i l 2 00 6 th at m an y oth er

ch l or i de sal ts ar e al s o sol u bl e i n wat er an d th er efor e mayb e

wor th testi n g. Cal ci u m c h l or i de an d pota ssi u m ch l or i de wer e

ch osen for tes ti n g du e to ava i l abi l i ty an d l o w h az ar d i n

h an dl i n g . B oth test sol u ti on s u se d 2 % r ati o to di sti l l ed water .

Th e col ou r an d ton al r an ge di ffer en ce bet ween each wa s sl i gh t

th er efor e fu r th er testi n g was n ot con si der ed n ece ssar y. Th e

fol l o wi n g Tabl e 1 -2 ou tl i n es th e per for man ce.

In order of light sensitivity In order of warmth of colour

1 . A mmon i a ch l or i de 1 . Potassi u m ch l or i de

2 . S odi u m ch l or i de 2 . A mmon i a ch l or i de

2 0

3 . Potassi u m ch l or i de 3 . S odi u m ch l or i de

4 . Cal ci u m ch l or i de 4 . Cal ci u m ch l or i de

Table 1-2 Other chlorides

B I N D E R S

B i n der s ar e th e su bstan ce s th at bi n d togeth er t wo or mor e

mater i al s or ch emi cal s i n a sol u ti on .

G E L A T I N B I N D E R

Th e gel ati n e bi n der su sp en ds th e ch l or i de sol u ti on al s o acti n g

as a si z i n g agen t . Th i s pr even ts th e si l ver par ti cl e s fr o m

si n ki n g i n to th e pa per fi br es; t h e i mage h as mor e acu tan c e

an d appear s br i gh ter .

0 . 2 % of gel ati n cau sed th e pr i n t to become co ol er i n col ou r . A s

th e per cen tage of gel ati n i n cr ea se d th e pr i n t bec a me war mer

an d a sl i gh t sh een app ear ed. 2 % of gel ati n cr eat ed a di sti n ct

su bstr ate el evati n g th e si l ver u p fr om th e paper . Th i s was

evi den t by th e i m pr oved vi si bl e sh ar pn ess of th e i mage an d

vi su al i mages fr om th e FE I No va Nan oS E M . L i gh t beg an to

r efr act i n th i s tr an sl u cen t ar ea a n d as wi th al bu men th e ton e s

became war mer . Gel a ti n bi n der s can b e com par ed i n F i gu r es 1 -

8 an d Fi gu r es 1 -9 for th e col ou r di ffer en ces.

A R R O W R O O T B I N D E R

A ccor di n g to wr i tten tex t ( R ei l l y, 1 9 8 0 ) ar r owr oot star ch es

acts a s a si z i n g an d cr eate a war m er ton e wh i l e en h an ci n g

detai l i n th e sh ado w r egi on . R ei l l y ( R ei l l y, 1 9 8 0 ) su ggests th at

th e si l ver n i tr ate sol u ti on r equ ir es ci tr i c aci d. A s “ star ch i s

n ot an acti ve or gan i c su bstan ce…i t h as n o eff ect on th e

r edu cti on of si l ver ch l or i de” ( R ei l l y, 1 9 80 p2 2 ) . However t e sts

wi th ar r o wr oo t wi th ou t ci tr i c aci d i n th e si l ver n i tr ate sol u ti on

pr oved th i s was n o t n eces sar y .

A r r owr oot wa s di ffi cu l t t o coa t bu t r esear ch u n cover ed an

ear l y for mu l a or i gi n al l y pu bl i sh ed i n 1 9 2 4 (Wal l an d Jor dan ,

2 1

1 9 75 ) . Th e per cen tag e of wat er wa s h i gh er an d so di u m

car bon ate i s i n cl u de d to ma ke i t l ess a c i di c. Th e odou r o f

ammon i a (fr o m a mm on i u m ch l or i de see ar r owr o ot f or mu l a on

page 9 3 ) was pu n gen t wh i l e m aki n g th e s ol u ti on , bu t th i s

r edu ced i n a fe w h ou r s . Th i s a m mon i a a ccel er ates t h e

sen si ti vi ty of th e star ch sol u ti on . S tar ch sol u ti on s appear ed to

si t i n th e space bet ween th e pape r fi br es . A s th e pa per dr i ed i t

became ma tt i n appear an ce. It th er efor e h as n ot th e same

l u mi n osi ty as al bu men or gel ati n .

A L B U M E N B I N D E R

Th e i mage si ts on th e su r face of th e paper pr ovi di n g th e

appear an ce of a gr eater den si t y r an ge th r ou gh th e r efr acti on

of th e l i gh t . It appear ed to r eso l ve fi n e detai l mor e th an th e

pl ai n sal ted pr i n t. D epen di n g on th e coati n g/ s ap pl i ed a n

al bu men pr i n t h as a sl i gh t sh ee n to gl oss y fi n i sh ed su r face,

pr ovi di n g br i l l i an ce , absen t i n sal ted paper pr i n ts.

B eati n g th e egg wh i te br eaks do wn th e al bu men i n to a u n i for m

con si sten c y . Th e sal t an d th e a ci d h el p wi th th e fer men ti n g of

th e al bu men s ol u ti on (se e al bu men for mu l a page 9 2 ) . Th e

sh or ter fer men tati on ti mes cr ea te d a du l l su r face. A fter t wo

we eks of fer men ta ti on th e su r face offer ed a better gl oss

fi n i sh . Th e su r face a ppear ed du l l wh en th e sol u ti on was

appl i ed u n der 1 5 ° C.

E i th er sodi u m an d a mmon i u m ch l or i de can be u sed i n th e

al bu men sol u ti on to cr eate si l ver ch l or i de , ammon i u m ch l or i de

cr eate s a col ou r 8 % to 1 0 % cool er th an sodi u m ch l or i de. (Th ese

col ou r di ffer en ces wer e cal cu l ate d fr om den si to meter

r eadi n gs)

Th e Fi gu r es 1 -8 to 1 -1 1 an d T abl e 1 -3 i n di cate th e di ffer ent

su r fac es, col ou r s an d ton e s fr om each of th e bi n der s.

2 2

Figure 1-8 0.2% Gelatin Binder

Figure 1-9 2% Gelatin Binder

Figure 1-10 Arrowroot

Figure 1-11 Albumen

0.2% Ge l ati n Bi nde r L* a. b. P anto ne ® S o l i d M att

S h ado ws B l ack M 1 2 1 0

M i d-ton es 7 5 18 4 0 1 9 1 7

2% gel ati n B i n der

S h ado ws 7 9 75 1 9 1 7 8

M i d-ton es 7 5 17 5 2 1 6 1 5

Arrowroot

S h ado ws B l ack m 1 2 1 0

M i d-ton es 4 7 05 4 0 1 9 1 7

Al bume n

S h ado ws 4 9 75 1 9 1 7 8

M i d-ton es 8 7 6 4 9 1 7 2 6

Table 1-3 Binders

Comp ar i son i n F i gu r e 1 -1 2 sh ows th e di ffer en t su r faces at

h i gh magn i fi cati on . A l th ou gh th e magn i fi cati on s ar e n ot

con si sten t 2 % of gel ati n sh o ws h o w i t si ts on th e fi br e su r face.

Th e 0 . 2 % of gel ati n an d star ch bin der s si ts bet ween th e fi br es

wh er eas th e al bu men bi n der com pl etel y con ceal s th e fi br es.

2 3

T H E S I L V E R N I T R A T E S E N S I T I Z E R

Figure 1-12 Binder surfaces

Th e l i gh t sen si ti ve su b stan ce i n sal t an d al bu men pap er i s

si l ver ch l or i de. S il ver ch l or i de is i n sol u bl e i n water . S odi u m

ch l or i de sol u ti on i s c oated on th e paper f ol l o wed by th e si l ver

n i tr ate sol u ti on , th u s cr eati n g si l ver ch l or i de an d sodi u m

n i tr ate. S odi u m n i tr ate i s sol u bl e an d i s wash ed a way du r i n g

th e pr ocessi n g.

Th e si l ver n i tr ate s en si ti z i n g sol u ti on wa s ma de u si n g

di sti l l ed or de -i on i z ed water . A n y con tami n ati on r esu l ted i n

cl ou dy wh i te pr eci pi tate of s i l ver ch l or i de an d si l ver

car bon ate. Th i s al so l i mi t ed th e ton al r an ge i n both th e

sh ado w an d h i gh l i gh t r egi on s of t h e pr i n t.

S i l ver n i tr ate i n i sol ati on i s n ot l i gh t sen si ti ve . It become s

ph otosen si ti ve i n th e pr esen ce of su bstan ce s th at r eadi l y

ox i di se. Th ese i n cl u de n ot on l y th e sal t sol u ti on s bu t paper

cel l u l ose, gel ati n or star ch .

D E C R E A S E T H E S I L V E R N I T R A T E P E R C E N T A G E

A smal l r edu cti on i n th e p er cen tage of si l ver n i tr ate i n th e

sol u ti on sh o wed ben efi t s i n pr i n ti n g h i gh con tr ast n egati ves.

A s th e per cen tage of si l ver r edu c ed fu r th er , th e pr i n ts became

we ak an d i n effecti ve .

Th e effect of de cr easi n g si l ver n i tr ate:

2 4

o 1 % sh owe d l i ttl e detai l i n th e h i gh l i gh ts an d th e mi d

ton es decr ease d i n c on tr ast. T h e sh ado w de tai l was

we ak. S po ts des cr i bed as „mea sl e s‟ appear ed after so me

ti me. M easl es ar e i l l u str ated i n Fi gu r e 1 -1 3 .

o 5 % i n cr eased th e war m th of th e col ou r an d th e pr i n t

beg an to l ose h i gh l i gh t detai l bu t gai n ed sh ado w det ai l .

O 1 0 % decr eased th e con t r ast a n d th e pr i n t appear s

war m er i n col ou r . Th e pr i n t was s ti l l sati sfactor y.

I N C R E A S E S I L V E R N I T R A T E P E R C E N T A G E

S mal l i n cr ease s i n th e per cen t age of si l ver n i tr ate i n th e

sol u ti on can be ben efi ci al i n pr in ti n g l ow con tr ast n egati ves .

A s th e per cen tage i n cr eased br on z i n g affect ed th e sh ado w

r egi on s an d yel l o wed th e h i gh l i gh ts , damagi n g th e pr i n t ‟ s

ton al r an ge .

R esu l t s of i n cr easi n g th e si l ver n i tr ate :

o 1 5 % i n cr ease d th e con tr ast . Th e col ou r was c ool er an d

sh o wed some l oss of detai l i n th e sh ado ws . Th e

h i gh l i gh t detai l wa s m or e appar en t . Th e pr i n t was s ti l l

acceptabl e.

o 2 0 % cr eate d fu r th er i n cr eas e i n th e con tr ast an d fu r th er

l oss of detai l i n th e sh ado ws . Th er e was s ome br on z i n g

an d mor e detai l i n th e h i gh l i gh ts .

o 3 0 % i n cr ease d th e con tr ast , al l owi n g l i ttl e det ai l i n th e

sh ado ws. B r on z i n g beca me obvi ou s wi th l es s detai l i n

th e h i gh l i gh ts. Th e h i gh l i gh ts be came yel l o w.

2 5

Figure 1-13 Measles

Figure 1-14 Silver Nitrate Variances

Fi gu r e 1 -14 i l lu str ate s th e effect di ffer en t per cen tages of

si l ver n i tr ate sol u ti on h a d on sal t pr i n t s. A 2 % sodi u m

ch l or i de sol u ti on was u se d i n al l tests .

A D D I T I V E S T O S I L V E R N I T R A T E

Ci tr i c A ci d i n th e si l ver n i tr ate sol u ti on (R ei l l y 1 9 8 0 ) i s

su ggested a s a pr eser vati ve of t h e sen si ti sed pa per . Ho wever

i t was f ou n d to pr eci pi tate ou t of th e si l ver n i tr ate sol u ti on

over a per i od of 2 to 3 h ou r s. The paper sen si ti se d wi th ci tr i c

2 6

aci d i n cl u ded e ffect s th e l i gh t sen si ti vi t y, th e r esu l ti n g

i mages app ear sl i gh tl y fogged, l o osi n g th ei r fu l l ton al r an ge.

Potassi u m di ch r o mate i n th e si l v er n i tr ate sol u ti on t o i n cr ease

th e con tr ast, as su gges ted b y (Jame s, 2 0 0 2 ) i mmedi atel y

pr eci pi tates cr eati n g si l ver ch r omate an d pota ssi u m n i tr ate

tu r n i n g th e sol u ti on br i gh t r ed.

E ach ch an ge or var i ati on to th e sal t sol u ti on cr eate d a

di ffer en ce to th e fi n al pr i n t. D r amati c di ffer en ces wer e

obser ved wh en i n cl u di n g pota s si u m di ch r oma te or s odi u m

ci tr ate i n th e sol u ti on . Th e rati o of sal t t o si l ver al so

per mi tted con tr ol over n ot on l y th e ton al r an ge an d con tr as t

bu t al so th e col ou r . If th e r ati o wa s to o far fr om th e n or m of

2 % sal t sol u ti on an d 1 2 % si l ver n i tr ate sol u ti on th e i mage l os t

ton e an d den si ty.

S i l ver n i tr ate sol u ti on s di d n ot b en efi t fr om an y ad di ti ves . B y

ch an gi n g th e per cen tage of th e si l ver n i tr ate i n th e sol u ti on ,

col ou r s an d th e ton al r an ge wer e con tr ol l ed .

2 7

C h a p t e r 2 T H E P A P E R

Th e or i gi n al paper s u sed b y Tal bot wer e 1 0 0 % cotton wr i ti n g

paper si z ed wi th gel a ti n fr om th e J. Wh at man 's 'Tu r key

M i l l ' . (S ch aaf, 2 0 00 )

Un der stan di n g th e ch ar acter i sti c s of paper wa s essen ti al wh en

deci di n g on paper s to te st . P ape r maki n g can be di vi ded i n to

th e fol l owi n g gr ou ps; h an d mad e, mou l d ma de an d ma ch i n e

made.

H A N D -M A D E : In di vi du al sh eets ar e mad e fr om cott on or l i n en

pu l p an d ar e h an dcr afted wi t h l i ttl e gr ai n wh i ch cr eates

gr eater str en gth . Owi n g t o avai l abi l i ty an d ex pen se on l y t wo

wer e ch o sen for th i s r esear ch .

C Y L I N D E R / M O U L D - M A D E : M ost wat er col ou r r ag paper s ar e made

fr om 1 0 0 % cotton or l i n e n . Qu a l i ty i s con si s ten t an d easi l y

avai l abl e. M ost of th e test wer e c ar r i ed ou t on th i s paper

M A C H I N E M A D E : Th ese wer e avoi d ed as th ey u su al l y con si st of

wood pu l p, l i gn i n , bl each es an d addi ti ves th at cau se ch e mi cal

foggi n g wh en ap pl yi n g si l ver n i tr ate sol u ti on s .

P A P E R C O M P O S I T I O N

S IZING: Th i s i n cr ease s su r fac e str en gth an d r esi st s th e

pen etr ati on of sol u ti on s i n to th e fi br es of th e paper . Gel ati n i s

th e most c om mon t yp e of si z i n g su i tabl e for sal t pr i n ti n g.

S UR FA CE S IZING i n di cates i t i s o n l y si z ed on o n e si de , mos t of

th e tests wer e car r i ed on su r face si z ed paper s .

TUB S IZIN G r efer s t o i m mer si n g dr y fi n i sh ed sh eet i n to a bath

of h ot gel ati n for mi n g a s ki n ov er th e paper su r face wh i ch i s

th en u su al l y h ar den ed .

2 8

INTE R NA L S IZING i s kn own as be ater or mach i n e. Th e si z i n g i s

added t o th e pr o ces s befor e t h e for mati on of th e sh ee ts

(Tu r n er , 19 98 ) .

FIL L E R S A ND L OA D INGS : M i n er al pi gmen ts bi n d th e fi br es

togeth er , fi l l i n g between th e gaps cr eati n g den ser sh eets

(Tu r n er , 19 98 ) . Th ese i n cl u de cal ci u m car bon ate (aci d bu ffer ),

Ch i n a cl ay (kaol i n ), ti tan i u m di o x i de an d opti cal br i gh ten er s.

A l l of th ese r eact ed wi th th e si l ver ch l or i de befor e ex posu r e,

cr eati n g ch emi cal foggi n g .

WA TE R L E A F: Th i s i s th e ter m fo r n o si z i n g , th ese ar e pap er s

ver y absor ben t a n d th er efor e ar e n ot su i tabl e for sal t pr i n ti n g .

Th ey cr eat ed fl at pr i n ts an d u n even col ou r s becau se of th e

i n con si sten t absor pti on r ates of th e sol u ti on s i n to th e pa per .

A l bu men h owe ver seal ed th e su r face of th e pa per th u s maki n g

i t u sabl e.

S U R F A C E F I N I S H I N G

R ou gh : Th i s was di ffi cu l t t o coat an d th e tex tu r e made th e sal t

pr i n t l ook fl at, du e to th e scatt er i n g of l i gh t r efl ect i n g fr om

th i s tex tu r e d su r face .

NOT: Col d pr ess ed , th i s m ean s i t i s n ot h ot pr es sed th r ou gh

r ol l er s. A br u sh was u sed to a p pl y th e coati n g an d a l th ou gh

some acu tan c e was l ost wi th t h e tex tu r e, th i s su r face was

aesth eti cal l y acc eptabl e.

Hot Pr ess : Th e s moo th fi n i sh i s ach i eved by u si n g h ot r ol l er s

or pr essed th r ou gh col d pol i sh ed metal r ol l er s . Th i s su r face

pr ovi de d th e gr eates t ton al r an ge an d acu tan ce. Th e col ou r s

wer e ea si er to eval u ate on th i s ty pe of su r face.

2 4 0 gsm to 3 5 0 gsm wer e easi er to u se f or sal t pr i n ti n g bu t

l i gh ter wei gh ts o f 1 8 0 gsm an d 1 4 0 gsm wer e te sted wi th

sati sfact or y r esu l ts . L i gh ter wei gh ts wou l d cu r l an d r equ i r e

tapi n g to a fi r m su r face. 1 40 gsm tor e at ti mes du r i n g th e wet

pr ocessi n g. Th e h eavi er paper s t ook l on ger for fi x er r em oval

to occu r .

2 9

C A R E O F P A P E R

Paper s wer e h an dl e d as l i ttl e a s po ssi bl e wi th wh i te cott on

gl oves. Fi n ger s l eft oi l s an d sal ts wh i ch i n cr e a se d th e

absor pti on r ate of th e sol u ti on cr eat i n g stai n s on th e pr i n t .

A n y su r face mar k s wer e r e move d gen tl y wi th a soft br u sh or

er aser . D i stu r b i n g th e su r face of th e paper made i t m or e

absor ben t an d appear ed a s a stai n on th e pr i n t .

P A P E R S S U I T A B L E F O R S A L T P R I N T I N G :

A l l paper t ests wer e car r i ed o u t u si n g 2 % sodi u m ch l or i de

sol u ti on an d 1 2 % si l ver ni tr ate sol u ti on u si n g th e con tr ol

n egati ve . Th i s u n i for mi ty al l owe d easi er compar i son s bet ween

th e per for man ce s of each of th e paper s. Th e r e su l ts ar e l i s ted

i n or der of th e abi l i ty of th e paper to r epr odu ce a fu l l ton al

r an ge an d acu tan ce . A l l paper s wer e a ci d-fr ee wi th n o op ti cal

br i gh ten er s an d Neu tr al pH. Th e fi ve best paper s wer e

magn i fi ed on th e Nova Nan oS E M to vi ew th ei r str u ctu r e. Th e

col ou r step - we dge s an d tabl e s h el p to an al yses col ou r s . Th e

poi n ter mar ks th e mi d-t on e an d sh ado ws on th e ste p - we dge

an d establ i sh es th e pa per base co l ou r .

B E R GGE R COT 3 20 M OUL D M A D E 3 2 0 gsm HP 1 0 0 %. Th i s paper

wa s n ot avai l abl e i n A u str al i a an d th e test sh eet s wer e

pu r ch ased di r ectl y fr om th e pa pe r wh ol esal er i n Fr an ce .

Th e h i gh magn i fi cati on s as sh o wn i n Fi gu r e 2 -1 i n di cates th e

l ar ge amou n t of gel ati n si z i n g. Wh en h ot pr essed i t pr ovi des a

h ar d su r face. Th i s h ar d co mp r essed su r face cr eates th e

cool n es s of th e pr i n t.

C ol ou r , T on es, a n d App ea ra n c e : Th e s al t pr i n t r esu l t ed i n a

cool deep br o wn col ou r . It h el d th e ton es i n both h i gh l i ght

an d sh ado ws , sh o wi n g 1 9 cl ear steps.

TA L B OT HA ND M A D E 2 40 gsm 1 0 0 % cotton h eavi l y gel ati n tu b

si z ed . Th i s i s n o t avai l abl e i n A u str al i a an d sa mpl e s wer e

pu r ch ased fr om th e R u sco mbe M i l l i n Fr an ce.

3 0

Hi gh magn i fi cati on s Fi gu r e 2 -2 sh o ws th e l ar ge amou n t o f

gel ati n si z i n g ; both i n an d on t h e su r face. Th i s h as n ot been

h ot pr ess ed l i ke th e B er gger paper , th e gel ati n r emai n s soft

n atu r al l y el ev ati n g th e si l ver ch lor i de pr ovi d i n g an ex tr emel y

war m col ou r .

C ol ou r , T on es, an d App ea ra n c e: Th e sal t pr i n t wa s a r i ch war m

br own col ou r . It h el d th e t on es i n both h i gh l i gh t an d sh ad o ws

sh o wi n g 1 9 cl ear steps. Th e Tal bot si z i n g was i n con si sten t

wi th so me fl a ws an d s pec k s th r ou gh ou t th e su r face . It wa s

i n con si sten t i n i ts per for man ce bu t th e qu al i ty of su cces sfu l

pr i n ts made i t wor th per si sti n g . Th e su r face beca me ver y s oft

wh en co ati n g th e sal t sol u ti on s. To en su r e an even coati n g of

si l ver n i tr ate sol u t i on th e sal ted paper was l eft t o „cu r e‟ for

2 4 h ou r s befor e sen si ti si n g . Th is l i gh ter wei gh t pap er cu r l ed

wh en moi stu r e wa s ap pl i ed an d n eed ed to be se cu r ed wh i l e

coati n g.

A R CHE S PL A TINE M OUL D M A D E (Fr en ch ) 3 1 0 gsm HP 1 0 0 %

cotton . Th e am ou n t of gel ati n s e en i n Fi gu r e 2 -3 , i s l es s th an

th e pr evi ou s t wo pa per s. A l th ou gh th i s com pr esse d su r face

cr eates co ol ton ed pr i n ts i t di d n ot el evate th e i m ages t o th e

same degr ee du e t o th e smal l er a mou n t of si z i n g.

C ol ou r , T on es P ap er App ea ra n ce: Th e sal t pr i n t wa s a c ool

br own col ou r . It h el d th e t on es i n both h i gh l i gh t an d sh ad o ws

sh o wi n g 1 8 cl ear steps. It h el d th e ton es ex tr emel y wel l an d

wa s con si sten t i n i ts per for man ce an d qu al i ty.

FA B R IA NO A R TIS TICO M O UL D M A D E (Ital i an ) 3 0 0 gsm HP 1 0 0 %

cotton . Th e gel ati n si z i n g a ppe ar s to be l ess th an pr evi ou s

paper s an d i r r egu l ar i n i ts cove r age (Fi gu r e 2 -4 ). Th e i mage

si ts i n th e fi br es wh i ch cu r bs th e ton al r an ge . Th e cr eam paper

col ou r base ma de th e t on es app e ar war mer .

C ol ou r T on es a n d Ap p ea r an c e : Th e paper wa s war m i n co l ou r

so th e h i gh l i gh ts wer e n ot as cl e an as th e pr evi ou s paper s . I t

h el d th e ton es i n bo th h i gh l i gh t an d sh ado ws sh o wi n g 1 6 cl ear

steps. Th e su r face si z i n g h el d th e ton es wel l .

3 1

B UXTON HA ND M A D E PL A TINOT YP E 2 4 0 gsm 1 0 0 % cotton HP .

Th i s i s u n -bu ffer ed an d i n ter n al l y si z ed wi th A l kyl -keten e -

di mer (A K D ) , a syn th eti c ar ch i val i n ter n al si z i n g agen t ; th i s i s

a h ydr oph obi c or water r ep el l en t si z i n g. Pr odu ced i n

R u scombe M i l l Fr an ce

Th e h i gh magn i fi cati on s i n Fi gure 2 -5 sh ow th e l ar ge amou n t

syn th eti c si z i n g. Th e i mage i s el evated by both th e si z i n g an d

th e al bu men bi n der . Th e tex tu re an d sl i gh t gl oss pr odu ce d

qu i te di ffer en t r esu l t to o th er p aper s. Th e ste p - wedge Fi gu r e

2 -1 0 i s al bu men coate d, al th ou gh n ot con si sten t wi th th e oth er

step we dges th e ch e mi cal foggi n g of th e sal t pr i n t wou l d n ot

al l ow a tr u e co mpar i son of th e t o n al r an ge .

C ol ou r , T on es a n d App ea ra nc e: Th i s paper wor ked ex tr emel y

wel l f or al bu men pr i n ti n g . It pr ovi ded r i ch pu r pl e br o wn ton es

wi th a fu l l ton al r an ge. B u x ton paper was n ot su i tabl e for sal t

pr i n ti n g . Wh en th e si l ver n i tr ate sol u ti on was appl i e d to th e

sal ted paper t h e A K D cr eated a ch emi cal fog , r edu ci n g th e

h i gh l i gh ts an d fl atten i n g th e sh ado w r egi on s . A l bu men

pr otected l ayer pr even t s th e si l ver n i tr ate fr om r each i n g th e

paper .

Figure 2-1 Bergger Paper High Magnifications

3 2

Figure 2-2 Talbot Paper High Magnifications

Figure 2-3 Arches Platine High Magnifications

Figure 2-4 Fabriano Artistico High Magnifications

Figure 2-5 Buxton Paper High Magnifications

3 3

Figure 2-6 Bergger Paper

Figure 2-7 Talbot Paper

Figure 2-8 Arches Platine

Figure 2-9 Fabriano Artistico

Figure 2-10 Buxton Paper

Be r g g e r P ape r b. L* a.

S h ado ws 0 P anto ne ® S o l i d M att B l ack m 1 2 1

M i d-ton es 7 1 1 m 4 2 4

Hi gh l i gh ts 1 2 7 4 99 m 9 2 -1

Paper base 7 7 4 85 m 9 0 -5

T al bo t P ape r

S h ado ws 2 3 1 4 5 m 2 0 1 7

M i d-ton es 3 0 4 6 35 4 5 1 9

Hi gh l i gh ts 2 1 6 7 0 m 9 4 -2

Paper base 1 2 7 4 99 m 9 2 -1

Ar c he s Pl ati ne

S h ado ws 8 4 9 75 m 1 7 1 9

M i d-ton es 6 1 0 m 4 7 4

Hi gh l i gh ts 1 2 7 4 99 m 9 2 -1

Paper base 1 2 7 4 99 m 9 2 -1

3 4

Fabr i ano Ar ti sti c o

S h ado ws 4 6 25 m 2 0 1 6 1 8

M i d-ton es 8 7 5 m 5 2 1 2 2 2

Hi gh l i gh ts 6 7 0 m 9 4 -2 2 1

Paper base 6 0 7 m 9 2 -4 2 1

Buxton Paper

S h ado ws B l ack m 1 2 1 0

M i d-ton es 7 5 18 m 4 0 1 1 1 0

Hi gh l i gh ts 7 4 01 m 9 2 1 1 8

Paper base 7 4 99 m 9 2 -1 1 4

Table 2-1 Paper Colours

Oth er paper s test ed :

S A UND E R S WA TE R FOR D (E n gl i sh ) 3 0 0 , an d 1 50 gsm HP 1 0 0 %

cotton . Th i s h el d ton e s wel l an d offer s ver y war m ton al r an ge.

It l ost th e h i gh l i gh ts to th e war m ton es of th e paper .

R IS ING S TONE HE NGE M A CHINE M A D E (E n gl i sh ) 2 4 5 gsm NOT

1 0 0 % cotton . A s i t i s bu ffer ed wi th cal ci u m car bon at e th e

sen si ti vi ty of si l ver n i tr ate cau se d foggi n g. Th e paper wa s

absor ben t cr eati n g a du l l pr i n t . A l bu men was n ot affect e d a s i t

i sol ates th e pa per fr om th e si l ver n i tr ate sol u ti on .

A R CHE S A QUA R E LL E M OUL D M AD E (Fr en ch ) 3 0 0 gsm H P 1 0 0%

cotton . Th i s i s an u n -bu ffer ed paper , i n ter n al l y an d su r face

si z ed wi th gel ati n e . It pr ovi d ed a r eason abl e ton al r an ge wi th

pl easan t war m ton e s.

FA B R IA NO TIE PE L O M OUL D M A D E Water col ou r ( Ital i an ) 2 9 0 gsm

1 0 0 % cot ton an d i n ter n al l y si z ed . Th i s was wel l pr i ced paper .

It wa s sof t su r faced paper wi th a h i gh absor pti on r ate

th er efor e u n su i tabl e for pl ai n sal ted pr i n ts . Th e r esu l ts

i mpr ove d wi th gel ati n an d al bu m en sol u ti on s.

3 5

L A NA QUA L L E M OUL D M A DE , 3 0 0gsm HP , 1 0 0 % cotton . Th i s i s

u n -bu ffer ed, i n ter n al an d ex ter nal l y si z ed wi th A K D . It i s w el l

pr i ced bu t th e r esu l ts wer e di s appoi n ti n g . Th e pr i n ts wer e

bl otch y du e to u n even abs or pti on ; even wh en bi n der s wer e

u sed i n th e sal t sol u ti on .

CR A NE ‟ S D IPL OM A PAR CHM E NT (US A ) (r epl acemen t for Cr an es

Pl ati n otype) M A CH I NE M A D E 1 7 7 gsm HP 1 0 0 % cotton r o si n an d

al u m si z ed. Th i s gave a r eason ab l e r esu l t bu t th e l i gh t wei gh t

paper t or e easi l y ma ki n g pr oces si n g di ffi cu l t.

CR A NE K ID FINIS H 17 7 gsm 10 0 % cotton u n -pr essed . Th i s

l i gh twei gh t paper n ee ded car efu l h an dl i n g wh en coa ti n g an d

pr ocessi n g .

A D D I N G S I Z I N G T O P A P E R

Th er e wer e ad van tages i n si z i n g paper befor e coati n g wi th th e

sal t sol u ti on s.

1 . It al l owe d u se of por ou s paper s t h at wer e n ot oth er wi se pr e-

si z ed.

2 . It cr eate d a di ffer en t fi n i sh to th e su r face .

3 . P aper s th at wer e h i gh l y tex tu r ed cou l d be u sed .

4 . Th i s was u sed a s a meth o d to c on tr ol th e col ou r .

Th e di ffer en t si z i n g tested:

o Gel ati n .

o Gel ati n h ar den ed wi th gl yox al .

Th e gel ati n si z i n g sol u ti on was kept ab ove 2 0 ° C or i t di d n ot

coat even l y . A sec on d co at of gel ati n assi st e d wi th coa ti n g

sol u ti on s on r ou gh tex tu r ed su r faces .

S i z i n g pr even t ed sol u ti on s fr om soaki n g i n to th e p aper maki n g

th e coati n g mor e u n i for m . A l thou gh h ot pr ess paper s wi th

h ar d su r faces ga ve th e sal t pr i n t s a bet ter defi n i ti on wi th a

cool col ou r , paper s wi th h eav y gel ati n si z i n g su ch as Tal bot

al so pr ovi ded war m col ou r s bu t s ti l l wi th a l on g ton al r an ge .

3 6

H A R D E N I N G T H E G E L A T I N S I Z I N G

Un for tu n atel y t h e ch e mi cal s u s ed for h ar den i n g gel ati n ar e

dan ger ou s .

A ddi n g sodi u m car bon ate to gl y ox al cr eates an al kal i n e b ath .

Th i s assi st s bi n di n g bet ween th e si z i n g an d th e h ar den er , the

h i gh pH max i mi s es th e h ar den i n g (Wal l s an d A ttr i dge, 1 9 77 ) .

Testi n g di sc over ed so di u m car bon ate r emai n ed i n th e paper

an d cr eated a ch emi cal foggi n g i n th e sal t pr i n t th er efor e

sodi u m car bon ate cou l d n ot be i n cl u ded.

1 0 0 % c otton pr oved to be th e most stabl e ba se for sal t

pr i n ti n g. Paper s made fr om ot h er fi br es wer e fou n d to b e

u n su i tabl e, r eacti n g wi th th e si l ver to cr eate a ch emi cal fog.

A n y addi ti ves apar t fr om gel ati n si z i n g, act as an ox i dan t wi th

th e si l ver ch l or i de cau si n g a ch emi cal fog, or n on i mag e

maki n g si l ver . A n al bu men coati n g pr even ted th e si l ver

ch l or i de fr om r each i n g th e pa per su r face al l o wi n g paper

n or mal l y n ot su i tabl e for sal t pr i n ti n g to be u sed.

Temper atu r e an d h u mi di ty i n fl u en ced th e absor pti on r ate of

th e sol u ti on s . Pa per s th at h ad l i ttl e or n o si z i n g wer e qu i te

por ou s an d th e s ol u ti on s s u n k i n to th ese types of pa per s .

Th ese ma de th e i mage l oo k s ofter , cr eati n g a du l l ma tt

appear an ce .

Tex tu r ed paper s wer e m or e di f fi cu l t to coat bu t t h i s was

over come by u si n g a br u sh to ap pl y th e s ol u ti on or si z i n g wi th

gel ati n befor e addi n g th e sol u tion s . Th e l i gh t scatter s fr om

th e tex tu r ed su r face s an d fl atten ed th e i mage appear an ce.

3 7

C h a p t e r 3 C O A T I N G T H E P A P E R

E n su r i n g th at th e sal t pr i n t coat i n g i s e ven an d c on si st en t i s

i mpor tan t t o eval u ati n g th e to n al r an ge an d col ou r s. Th i s

ch apter ex pl or e d ways of coati n g an d th ei r effects.

Coati n g paper can be br o ken i n to 3 basi c meth od s ; fl oati n g th e

paper i n a ba th of sol u ti on , b r u sh i n g on , or pu sh i n g th e

sol u ti on wi th a gl ass r od.

FL OA TING OR S UB M E R GING IN A S OL UTIO N B A TH : Th e paper

can be compl etel y su bm er ged, or fl oat on th e su r face o f th e

sol u ti on . S u bmer si on i n th e sal t sol u ti on cr eate d a fl at i mage

as th e si l ver seem e d to si t d e eper i n to th e paper . It was

di ffi cu l t to es ti mate th e amou n t of sol u ti on th at was ab sor bed

wh en fl oati n g th e paper on th e sol u ti on . C oati n g th e si l ver

n i tr ate i n th e bath was n ot atte mpted du e t o th e dan ger of

h an dl i n g l ar ge qu an ti ti es of th i s sol u ti on .

B R US HING : B r u sh es wi th n o met al par ts mu st be u sed as th e

metal r eacts wi th th e sol u ti on s . Th e ex ampl es tes ted wer e

h ake br u sh , spon ge br u sh es an d B u ckl e br u sh es (cotto n wool

twi sted i n t o a test tu be) . Car e wa s n eede d to en su r e th e

coati n g was even an d i t wa s di ffi cu l t to esti mate t h e amou n t

of sol u ti on u sed t o coa t th e paper . Th i s me th od was n o t

econ omi c al as th e br u sh r etai n ed some of th e sol u ti on .

PUS HING OR D R A GGING THE S OL UTIO N : Gl as s pu ddl e pu sh er s

or ch emi cal pu sh er s pu sh a pool of th e sol u ti on even l y acr oss

th e paper . B y measu r i n g th e sol u ti on ou t wi th a syr i n ge th i s

coati n g sys tem wa s econ omi c, fas t an d r el ati vel y pr eci se.

C H E M I C A L P U S H E R S

Hei n er Peter sen of Peter sen S ci en ti fi c Gl ass ma de th e fi r st test

ch emi cal pu sh er s f or th i s pr oject . Th ese wer e ma de fr om gl a ss

r ods 1 0 mm i n di amet er wi th a cen tr al h an dl e at tach ed.

A l th ou gh r el ati vel y su ccess fu l , th ey wer e n ot al wa ys

3 8

compl e tel y str ai gh t , l eavi n g ar eas wi th n o sol u ti on on th e

paper .

Hei n er su ggested du r i n g a tel eph on e

con ver sati on on 6 t h of Ju n e 2 0 0 6 to u se r ou n d

gl ass t u bes kn o wn as capi l l ar y gl ass , 1 0 mm i n

di ameter wi th 2 mm wal l s as i l l u str ated i n

Fi gu r e 3 -1 Th ese wer e ben t i n to a tr i an gu l ar

Figure 3-1 Glass Rod sh ape so th ey cou l d be h el d wi th on e h an d .

S A L T C O A T I N G

Th e amou n t of s ol u ti on r equ i r ed ch an ge d wi th :

1 . Hu mi di ty .

2 . Heat.

3 . Paper su r fa ce.

Wh en u si n g a h i gh er per cen tage of gel ati n i n th e sal t sol u ti on ,

th e paper an d th e s ol u ti on wer e h eated to 2 0 ° C. Th i s s top ped

th e on set of th e gel ati n setti n g an d „dr aggi n g ‟ u n even l y do wn

th e paper . In cr easi n g th e qu anti ty of fl u i d appl i ed to th e

paper al so ease s th i s pr obl em.

A l l owi n g th e s ol u ti on to soak i n befor e u si n g war m ai r to dr y

th e paper gav e a mor e c on si sten t an d even su r face. A ppl yi n g

ex cessi ve h eat wh i l e sti l l qu i te damp , dr i ed th e sal t on th e

su r face l eavi n g sal t cr ystal tr ai l s or patch es.

A L B U M E N C O A T I N G

A l bu men wa s mor e di ffi cu l t t o coat th an pl ai n sal t ed paper .

B u bbl es an d l u mp s of sol u ti on cr eate d dar k spo ts an d ci r cl es.

Un even pat ch es sh o wed as di ff er i n g den si ti es i n th e fi n al

pr i n t. Th er e was var i ati on fr om on e sol u ti on to an oth er , some

bei n g qu i te gl u ten ou s an d sti cky. Th i s i s du e to th e h en ‟ s di et

wh i ch af fects th e wh i te of th e egg. A ddi n g a l i ttl e mor e

3 9

di sti l l ed wat er u su al l y sol v ed th i s pr obl em. Coati n g was f ou n d

easi er wh en th e fol l o wi n g step s wer e ta ken .

In cr easi n g th e a mou n t of sol u ti on appl i ed. Th e o

ex cess s ol u ti on al l o ws c on tr ol o ver th e smooth n e ss

of th e coati n g.

o A ddi n g 0 . 5 % of wetti n g agen t t o t h e al bu men sol u ti on

wa s su gges ted i n som e tex t s to r edu ce ai r bu bbl es

(R ei l l y, 1 98 0 ) . In pr acti ce n o si gn i fi can t di ffer en ce

wa s fou n d .

o R emov i n g an y ex ce ss al bu men a r ou n d th e edges of

th e pr i n t; th e ex ces s for m s h ar d l u mps wh i ch mad e i t

di ffi cu l t to move th e r od even l y acr oss th e paper

wh en ap pl yi n g th e si l ver n i tr ate sol u ti on .

Th e ease of c oati n g i n cr eases a s th e al bu men ages. (Webb an d

R eed, 2 0 0 0 ) state th at th e sol u ti on can be u sed i mme di atel y.

Ho wever oth er tex ts su gge st th a t after th e fi r st twen ty f ou r

h ou r s i t sh ou l d be fi l ter ed th r ou gh ch eesecl oth , fol l o wed b y a

fer men tati on per i od of t wo da ys (Ja mes, 2 0 0 2 ) on e week

(Far ber , 19 9 8 , R ei l l y, 1 9 80 ) and M i ke R obi n son i n B ar n i er,

(2 0 00 ) .

A gl ossi er fi n i sh f or th e al bu men wa s cr eated by dr yi n g th e

su r face at a bou t 3 0 ° C .

Th e si l ver n i tr ate coati n g s ets o r coagu l ates th e fi r st coati n g

so th er e was n o n eed t o h ar den th i s u n l ess a se con d coat of

al bu men wa s pr efer r ed . A secon d coat i n cr eases th e su r face

gl oss, th er eby pr odu ci n g an ex tr a br i l l i an ce to th e al bu men

pr i n t. Har den i n g i s e ssen ti al t o avoi d s often i n g th e fi r st

al bu men coat wh i l e appl yi n g th e secon d.

Th e fol l o wi n g meth o ds of h ar den i n g wer e test ed:

1 . S tor i n g for fou r mon th s en su r ed th e al bu men wa s

su ffi ci en tl y „cu r ed‟ an d was h a r d en ou gh to accept a

secon d c oat .

4 0

2 . S teami n g th e su r face of th e fi r st coati n g for 1 mi n u te.

(Far ber , 1 99 8 ) . Th e si l ver n i tr ate sol u ti on soften e d th e

al bu men sol u ti on i n l es s th an on e mi n u te . Th er efor e wa s

n ot con si der ed su cces sfu l .

3 . Pl ace a pi ece of paper over th e su r face of th e dr y

al bu men coated paper . S et an i r on at max i mu m

temper atu r e an d move even l y o ver th i s paper (James,

2 0 02 ) . Th e si l ver n i tr ate s ol u ti o n soften e d th e al bu men

sol u ti on i n l ess th an on e mi n u te . Th er efor e th i s was n ot

con si der ed su c ces sfu l .

4 . Pl aci n g th e pr i n t i n a bath of 7 0 % i sopr op yl al coh ol f or

1 5 secon ds . Th i s me th od was co n ven i en t as th er e i s n o

wai ti n g ti me an d i t pr oved to per for m as wel l as th e

agei n g meth od.

M ost tex t s advi se th at 2 % am mon i u m ch l or i de sh ou l d b e adde d

to t h e bath of i sopr o pyl al coh ol as th e bath l ea ch es th e

ch l or i de fr om th e fi r st c oati n g (Jame s, 2 0 0 2 ) (R ei l l y, 1 98 0 )

r ei ter ated by Far ber 1 9 9 8 , an d Mi ke R obi n son (B ar n i er , 2 0 0 0 ).

Nu mer ou s test s wer e car r i ed ou t pr ovi n g th e added ch l or i de

i n cr eased ex po su r e ti me dr amati cal l y an d th e pr i n t was pal e

an d weak. Th e ex tr a ch l or i de decr ea sed th e con tr as t

con si der abl y. R ei l l y (emai l 18 t h D ecember 2 0 07 ) str on gl y

su ggested th at i t wa s a „ mi sta ke ‟ to add ch l or i de to th e

i sopr opyl al c oh ol ; th i s appear s to con tr adi ct h i s 1 9 8 0 tex t.

A R R O W R O O T ( S T A R C H ) C O A T I N G

E ven after fi n di n g a for mu l a th at gave con si sten t coati n gs ,

ar r owr oot sti l l pr oved t o be th e most di ffi cu l t sol u ti on t o

coat . Th i s di ffi cu l ty was r esol ve d by i n cr easi n g th e amou n t of

sol u ti on appl i e d to 6 ml for an 8 x 1 0 pr i n t. 3 ml s i s appl i ed at

th e top of th e page an d 3 ml of s ol u ti on at th e bo tto m ,

pr ovi di n g an even coati n g .

4 1

A defi n ed mar k was l ef t on th e paper i f th e r od stop ped

pu sh i n g fl u i d i n th e i mage ar ea, even for a fe w se con ds. Th i s

wa s du e to th e r api d abs or pti o n cr eated b y a mmon i a. Paper

sen si ti sed l es s th an th r ee h ou r s after th e s tar ch coati n g

decr eased ex posu r e ti mes b y 5 0 % . Th i s was du e to a mm on i a

i n cr eas i n g th e sen si ti vi ty of th e si l ver ch l or i de . Th er e was a

r api d absor pti on r ate of th e si l ver n i tr ate sol u ti on i f th e

ar r owr oot c oati n g was n ot l eft t o „cu r e‟ . Un l ess th er e was a

su bstan ti al i n cr ease of th e si l ve r n i tr ate sol u ti on t h e c oati n g

wa s u n even . L eavi n g th e coate d paper to cu r e for a mi n i mu m

of t wel ve h ou r s pr ovi de d a stabl e su r face wi th n or mal

ex posu r e ti mes.

S E N S I T I Z I N G T H E S A L T E D P A P E R

A s th e si l ver n i tr ate sol u ti on i s appl i ed th e paper become s

l i gh t sen si ti ve to u l tr a vi ol et l i gh t an d th e vi si bl e spe ctr u m u p

to 6 4 5 n m. A 5 0 watt i n can descen t l i gh t wa s se t at 1 . 5 m fr om

th e wor ki n g su r face s wh er e s en si ti si n g was car r i ed ou t .

Fl u or escen t l i gh ts wer e en cased wi th a UV fi l m bl o cki n g th e

spectr al l i gh t r ays bel ow 4 0 0 nm. Tests wer e per for med to

en su r e n o l i gh t wou l d „fog ‟ th e sal t pr i n t du r i n g sh or t peri od

of ti me (u p to fi ve mi n u tes) r e qu i r ed du r i n g th e sen si ti z i ng

step. Th e sen si ti sed paper was s tor ed i n th e dar k u n ti l r eady

for u se.

E ar l i er meth ods of sen si ti si n g wer e per for med by fl oa ti n g th e

sal ted pa per on th e su r face of a bath of si l ver n i tr ate sol u ti on .

Th i s i s con si d er ed a dan ger o u s pr acti ce an d a wa stefu l

meth od, u si n g l ar ge amou n t s of si l ver n i tr ate. A n u mber of

tex ts i n cl u di n g (Ja mes, 2 0 0 2 ) (R ei l l y, 1 9 80 , B ar ni er , 20 0 0 ) and

(B ar n i er , 20 0 0 ) sti l l today r eco m men d th i s me th od. Cr a wfor d

(1 9 79 ) fool i sh l y su gges ts th at i t i s con si d er ed a badg e of

h on ou r to stai n you h an ds wi th si l ver n i tr ate !

Th e u se of a gl ass r od an d th e syr i n ge meth od of coa ti n g

pr oved to be th e safes t meth od avoi di n g al l con tact wi th th e

4 2

si l ver n i tr ate sol u ti on . Th e same qu an ti ty of si l ver n i tr ate

sol u ti on i s u sed a s for th e sal t sol u ti on . Th er efor e i f 2 ml of

sal t sol u ti on i s u sed th en 2 ml of si l ver n i tr ate sol u ti on wa s

al so appl i ed .

B y u si n g a g l ass r od an d a syr i n ge ( wi th ou t th e n eedl e ) i t was

easy to c on tr ol th e amou n t of si l ver n i tr ate sol u ti on appl i ed.

Th e ex act a mou n t of si l ver n i tr ate sol u ti on can be dr a wn u p

i n to th e syr i n ge fr om th e bo t tl e. On ce pr acti se d at th i s

meth od, th e c oats be came ev en , th e r ati o bet ween th e sal t an d

th e si l ver n i tr ate sol u ti on was con tr ol l ed an d th e coa ti n g

dr i ed qu i ckl y.

Coa ti n g th e si l ver n i tr ate on t o th e dr y so di u m ch l or i de c oati n g

cr eat es si l ver ch l or i de , th e i m agi n g maki n g com pou n d an d

sodi u m n i tr ate wh i ch mu st be wa sh ed ou t of th e pr i n t after

ex posu r e.

S E N S I T I Z I N G A L B U M E N P A P E R

i n cr easi n g th e o A s wi th th e al bu men ch l or i de sol u ti on ,

amou n t of si l ver i n th e syr i n ge o r on th e br u sh en su r e d easy

appl i cati on , al so mi n i mi s i n g th e bu bbl es. Th e bu bbl es ar e

cr eated by th e sof ten i n g of th e al bu men sol u ti on .

o E ach bu bbl e r emai n i n g on th e paper l eft a dar k ci r cl e i n th e

i mage.

S E N S I T I Z I N G A R R O W R O O T P A P E R

Ci tr i c aci d i n th e si l ver n i tr ate s ol u ti on i s sai d t o decr eas e th e

ex posu r e ti me an d d ecr ease th e con tr ast . Wh i l e i n cr easi n g

sen si ti vi ty, th e ci tr i c aci d i n th e si l ver n i tr ate sol u ti on make s

th e paper mor e di ffi cu l t t o t o n e (Cr a wfor d, 1 9 7 9 ) . A ddi n g

ci tr i c aci d to th e si l ver n i tr ate sol u ti on decr ease d th e

ex posu r e ti me an d br on z i n g became an i ssu e i n th e sh adow

r egi on s. Th i s appear s to con tr adi ct th e n eed t o i n cr eased

sen si ti vi ty of th e si l ver n i tr ate sol u ti on .

R ei l l y states th at a r r owr o ot r equ i r es a str on ger si l ver n i tr ate

coati n g an d n eed s to be a ppl i e d r api dl y du e to th e star ch ‟ s

4 3

sol u bi l i ty (R ei l l y, 1 9 80 ) . In pr acti ce h o wever , i t was fou n d

u n n ecessar y to i n cr ease th e str en gth of th e si l ver n i tr ate

sol u ti on . Th e coa ti n g pr obl em wa s s ol ved b y appl yi n g an

i n cr eased am ou n t of th e si l ver n i tr ate sol u ti on an d dr ai n i n g

off th e ex cess.

S T O R A G E O F S E N S I T I Z E D P A P E R

Tr i al s pr oved th at stor i n g sen si ti z ed paper du l l s th e pr i n t.

S ome ch emi cal f oggi n g appear s after ti me, dep en di n g o n

temper atu r e an d h u mi di ty. T h e h i gh l i gh ts l os t th ei r cl ar i ty

an d th er e was l o ss of o ver al l den si ty an d sen si ti vi t y to l i gh t.

A l bu men star t ed to sh o w yel l o w i n g i n th e hi gh l i gh ts. It was

fou n d th at s tor i n g i n tem per at u r es bel o w 5 ° C l o wer ed th e

sen si ti vi ty an d th e foggi n g cou l d be del ayed for u p to fou r

h ou r s.

In su mm ar y g l as s r ods wer e f ou n d to b e an e con o mi c, pr eci se,

fast an d eas y m eth od for co ati n g an d ea si l y wa sh ed to r em ov e

al l ch emi cal tr ace s. Ho wever gl a ss r od s wer e n ot su i tabl e for

h i gh l y tex tu r ed su r faces . Pu sh i n g th e fl u i d do wn th e paper can

be di ffi cu l t an d th e r od may „br u i se‟ th e peaks o f th e tex tu r e .

On ce th e ch l or i de was o mi tted fr om i sopr o pyl al coh ol for

h ar den i n g th e al bu men th i s was c on si sten tl y su cces sfu l wh en

appl yi n g th e secon d coat.

L eavi n g th e most sa l te d paper to cu r e for twen ty -fou r h ou r s

r edu ced th e moi stu r e con t en t pr o vi di n g a mor e stabl e coati n g

su r face for th e si l ver n i tr ate sol u ti on . D espi te l i ter atu r e to th e

con tr ar y, s tor age of sen si ti sed pa per wa s u n sati sfact or y o wi n g

to th e decr ease i n sen si ti vi t y an d foggi n g.

4 4

C h a p t e r 4 T H E N E G A T I V E

Th e sal t pr i n t i s a con tact pr o c ess r equ i r i n g a n egati ve th e

t h a n p r o c e s s e d o u t p a p e r s , m i n u t e s t o h o u r s a s o p p o s e d t o s e c o n d s

i n a n e n l a r g e r . T h e e n l a r g e r l i g h t i s n o t s t r o n g e n ou g h t o e x p o s e

s a l t p r i n t s . U V i s r e q u i r e d f o r e x p o s u r e a n d t h e n e g a t i v e m u s t b e in

“c o n t a c t ” wi t h t h e s e n s i t i s e d p a p e r .

same si z e as th e desi r ed pr i n t. E x p o s u r e s a r e c o n s i d e r a b l y l o n g e r

Th e n egati ve s wer e ex pose d on 8 x 1 0 fil m to h el p ampl i f y

di ffer en ce s bet ween ea ch fi l m t y pe. A ste p we dge wa s pl ac ed

i n th e i mage , l ar ge en ou gh to r ead on a den si to meter . Th i s

el i mi n ated th e n eed to en l ar g e th e i mag e , mi n i mi z i n g an y

ar tefacts th e di gi tal scan may i n tr odu c e. Th e most su cces sfu l

an al ogu e fi l m n egati ve was sel ec ted as th e con tr ol t o com par e

al l oth er n egati ve types .

S el f -mas ki n g i s fu n damen t al i n pr odu ci n g th e sal t pr i n t ‟ s

ex ten ded ton al r an ge. Th i s i s cr eated by t h e si l ver ch l or i de

con ver t i n g to metal l i c si l ver du r i n g ex posu r e , th u s bl ocki n g

th e sh ado w ar eas ( th e l i gh t par t of th e n egati ve). Th i s sl o ws

th e ex posu r e to th e sh ad o w r egi o n al l owi n g th e h i gh l i gh ts ( th e

den se/ dar k par t of th e n e gati v e) to con ti n u e pr i n ti n g. Th e

sel f -ma ski n g per mi t s a gr adati o n of l i gh t ton es wh i l e sti l l

h ol di n g sh ado w d etai l . Cor r ect n egati ve den si ty i s th er efor e

i mpor tan t for th e h i gh l i gh ts so t h ese l i gh ter ton es do n o t over

ex pose. Negati ve s, wh eth er di gi t al or an al ogu e, ar e cr i ti cal to

th e pr i n t s t on al r an ge. Th i s ch apter ex pl or es th e di ffer en t

wa ys of pr o du ci n g n egati ves.

T Y P E S O F N E G A T I V E S

A l th ou gh n egati ves fal l i n to two major gr ou ps , an al ogu e an d

di gi tal , th ese gr ou ps do i n ter l ace . A n an al ogu e n egati ve can be

pr odu ced fr o m a di gi tal fi l e an d an al ogu e n egati v es can be

di gi ti sed to cr eate i n kj et n egati v es.

4 5

A N A L O G U E C O N T I N U O U S T O N E F I L M N E G A T I V E S

A n al ogu e n egati ve s h ave tr adi ti on al l y pr ovi de d an ex cel l en t

con ti n u ou s ton e. D evel o pmen t c on tr ol s can pr ovi de th e ex tr a

den si ty r equ i r ed for sal t pr i n ts.

Cer tai n di sadvan tag es c ome wi t h u si n g fi l m. Th e n u mber o f

bl ack an d wh i te fi l m s avai l abl e o n th e mar ket h as con ti n u ed t o

decl i n e si n ce th e i n tr odu cti on of di gi tal captu r e camer as.

3 5 mm an d medi u m for mat fi l ms mu st be en l ar ged for con tact

pr i n ti n g by mean s of i n t er -n eg ati ves or r ever se pr oc essi n g.

Th ese mater i al s ar e ex pen si ve an d dar kr oo m f aci l i t i es f or

pr ocessi n g ar e r eq u i r ed.

F I L M S T E S T E D

I L F O R D FP4 F I L M 12 5 IS O Th i s fi l m cr eate d a wi de t on al r an ge

ex ten ded by th e ch ar acter i sti c l o w fi l m bas e fog . A s a r e su l t of

th i s l o w fi l m base fog an d sl o wer spee d Il f or d‟ s HP4 fi l m

offer ed th e best r esu l t wi th most d evel oper s. Te sts wer e

car r i ed ou t at 8 0 IS O, 1 0 0 IS O, 1 25 IS O an d 2 00 IS O

I L F O R D HP5 40 0 IS O. Th i s fi l m offer s Si mi l ar qu al i ti es to o

th e Il for d FP4 fi l m . Ho we ver th e fi l m ba se wa s n ot as

cl ear an d di d n ot ex ten d th e t on al r an ge to th e sa me

degr ee . Th i s was te sted at 2 5 0 ISO an d 4 5 0 IS O

o F O M A P A N C L A S S I C 2 0 0 IS O. Th e PMK devel oper war med th e

n egati ve col ou r . Ho wever th i s f i l m emu l si on an d base

fog com pr esse d th e sal t pr i n t ton al r an ge.

o F O R T E F O R T E P A N 1 0 0 IS O fi l m r ated at 1 0 0 an d 20 0 IS O

B ase fog l i mi ted th e ton al r an ge cr eat i n g si mi l ar r esu l ts

to Fomap an , agai n compr es si n g th e sal t pr i n t ton al

r an ge .

o F O R T E F O R T E P A N 2 0 0 IS O fi l m Tests at 2 0 0 an d 40 0 IS O

both sh o wed th e b ase fog an d fi l m emu l si on l i mi ted th e

ton al r an ge . However , th i s per for med sl i gh tl y better

th an For te For tep an 1 0 0 IS O.

4 6

o R O L L E I S H E E T F I L M 2 5 IS O to 6 4 00 IS O r ate d at 20 0 IS O.

Th e fi l m emu l si on an d base fog agai n l i mi ted th e ton al

r an ge gi vi n g si mi l ar r esu l ts to F omapan .

Fi l m b ase fog or c h e mi cal f oggi n g of com mer ci al fi l m s i s par t

of th e devel opm en t pr oce ss cau s i n g den si ty i n th e h i gh l i gh ts

an d r edu ci n g th e con tr ast of th e fi l m. Th i s fog may al so take

pl ace du r i n g poor stor age or ag ei n g. Il for d FP4 wi th th e l o west

fog base pr oved t o pr ovi de th e b est r esu l ts .

F I L M D E V E L O P E R S T E S T E D

A l l devel oper s wer e teste d at both r ecomm en ded an d

i n cr eased ti me s, var yi n g str en gth s an d temper atu r es .

PM K D E V E L O P E R Th e ox i di si n g acti o n of th e pyr ogal l ol devel o per

h ar den s th e gel ati n , cr eati n g a r el i ef on th e fi l m su r face. Th i s

l eaves a gr een / yel l o w/ br o wn s t ai n . To fu r th er th e t an n i n g

pr ocess (Hu tch i n gs, 1 9 9 2 ) su ggests pl aci n g th e n egati ve back

i n th e devel oper . Th i s h o wever fl atten ed th e ton al r an ge an d

th er efor e n ot u sed i n th e devel o pi n g pr ocess es. PM K pr ovi ded

th e best ton al r an ge to th e sal t pr i n t i n al l fi l m test s. Th e

for mu l a for th i s devel oper i s s et ou t i n A ppen di x 3 of th i s

paper .

o A G F A R O D I N A L D E V E L O P E R Th i s for m u l a dates ba ck t o 1 8 8 0 s

an d i s con si der ed a h i gh defi n i t i on devel oper wi th

en h an ced acu tan ce an d i s acce pt ed as a good al l r ou n d

devel oper (A n ch el l , 2 00 0 ) . A l th ou gh i t per for med

r eason abl y wel l i t di d mat ch th e ton al r an ge of th e PM K .

Th i s i S Pyr ocate ch ol -ba sed o P Y R O C A T -HD D E V E L O P E R

devel oper wh i ch i s sai d t o pr o du ce si mi l ar r esu l ts t o

PM K devel oper s . It pr o du ces a bl u e/ br own stai n i n s tead

of th e gr een / br own stai n l eft by PM K . Th i s pr odu ces a

l i mi ted ton al r an ge.

i s th e most co mm on l y u sed o K O D A K D 7 6 D E V E L O P E R

devel oper du e to i ts stabi l i ty a n d pr edi ctabi l i ty . Th i s

di d n ot pr ovi de an adequ ate t on al r an ge.

4 7

I N C R E A S I N G T H E T O N A L R A N G E P O S T D E V E L O P M E N T

Negati ve r edu cer s ar e n or mal l y u sed to r edu ce th e den si t y of

fi l m wh en over devel o ped or ove r ex posed. Th i s wa s ex pl or ed

as a way t o i n cr ease th e ton al r a n ge by r edu c i n g th e ch emi cal

fog .

o A mmon i u m th i osu l fat e an d ci tr i c aci d. Th i s r edu ced

sh ado w r egi on bu t di d n ot r edu ce th e h i gh l i gh ts to th e

same degr ee .

o K odak R -4 b: D espi te th e stateme n t th at i t r emoved th e

fog base (A n ch el l , 2 0 0 0 ) i t pr oved to r e move th e den si t y

i n th e h i gh l i gh ts al so.

o Far mer s R edu cer r emoved th e fog base bu t al so r emove d

th e den si ty i n th e h i gh l i gh ts .

Negati ve i n ten si fi er s ar e gen er al l y u sed to i n cr eas e th e fi l m ‟ s

den si t y wh en ei th er u n der ex pos u r e or u n der devel opmen t h a s

occu r r ed .

o S el en i u m sol u ti on of 1 : 1 0 for 10 mi n u tes i n cr eased th e

h i gh l i gh t ‟ s den si ty, i n cr eas i n g th e ton al r an ge by 2

stop s wh i l e i n cr easi n g th e sh a do w r egi on t o a l e sser

degr ee .

S el en i u m wa s th e on l y s u cce ssfu l agen t to i n cr ease th e ton al

r an ge u si n g a post devel op men t p r ocess.

R E S U L T S O F A N A L O G U E N E G A T I V E S T E S T S

Th e combi n ati on of HP4 fi l m an d PM K devel oper pr odu ced th e

best sal t pr i n t n egati ve s . Th e n egati ve s wer e ex po sed for th e

sh ado ws , r ati n g th e fi l m at 1 00 IS O. Th e str en gth of th e

devel oper sol u ti on was dou bl e d t o i n cr ease th e fi l m den si ty.

M an y of th e n egati ve s tested app ear ed to pr ovi de a good r an ge

an d den si to meter r eadi n gs see m ed to con fi r m th i s. Ho wever

th e pr i n t test s di d n ot match th e ex pecte d r esu l ts, ex c ept f or

th e FP4 fi l m i n PM K devel oper . Ch emi cal fog seem ed to i mp ede

4 8

th e i n for mati on i n th e h i gh l i gh t an d mi d -ton e r egi on s.

A n al yses i n di cate d th at th e gr ee n / br own of th e PM K n egati ve

con tr ol s th e wa y th e UV spectr u m tr an smi ts th e l i gh t t o th e

sen si ti sed p aper , ex ten di n g th e ton al r an ge. Th e PMK stai n s

th e gel ati n base pr opor ti on al l y t o th e den si ty , th e den ser th e

r egi on th e gr eater stai n i n g. Fu r th er , th e swel l i n g or r el i ef

vi si bl e acr os s th e n eg ati ve su r face app ear s to add an ex tr a

di men si on .

Th e fol l o wi n g fi gu r es, ch ar t an d tabl es s et ou t h o w each of th e

fi l ms wer e teste d an d r ecor ded . Fi gu r e 4 -1 A . i s th e an al ogu e

n egati ve fi l m an d fi gu r e 4 -1 B . i s th e r esu l ti n g sal t pr i n t. Th e

Tabl e 4 -1 sets ou t th e r eadi n gs taken on th e den si tomet er

fr om th e fi l m, wh i ch ar e con ver t ed to th e Ch ar t 4 -1 . Th e same

r eadi n g meth od was u sed f or each fi l m t ested an d th e

r esu l ti n g pr i n t . M or e th an 1 5 0 tests wer e car r i ed ou t ; th ei r

i n cl u si on was c on si der ed u n wi el dy for th e r eader . Th ese are

avai l abl e for vi ewi n g i f so r equ i r ed.

A B

Figure 4-1 A Negative and B Salt Print

4 9

Film No. Date:

Development

FP4 30 26/10/06

Pre-

Dev..Time Dev..Temp Dev. Type Stain wash

7 min 26 C PMK 2:4:100 No No

Cyan Magenta Yellow VIS Steps

1 0.30 0.30 0.33 0.35

2 0.63 0.60 0.68 0.65

3 0.75 0.73 0.85 0.80

4 0.78 0.76 0.89 0.83

5 0.85 0.83 0.98 0.90

6 0.96 0.94 1.11 1.01

7 1.01 0.99 1.17 1.06

8 1.07 1.05 1.24 1.12

9 1.13 1.10 1.32 1.18

10 1.21 1.19 1.42 1.26

11 1.29 1.26 1.52 1.34

12 1.37 1.34 1.62 1.42

13 1.46 1.43 1.73 1.51

14 1.55 1.52 1.85 1.60

15 1.64 1.60 1.95 1.69

16 1.73 1.70 2.05 1.78

17 1.83 1.80 2.18 1.87

18 2.03 1.99 2.41 2.07

19 2.12 2.09 2.52 2.16

Density

1.82 1.79 range 2.19 1.81

Image

Film Exposure

Av density

density

EI

ISO speed

Aperture

units

units

1.74

1.2

1.90

100 MAR

f32

Table 4-1 Film Density Readings

5 0

FILM No FP4 30 PMK developer 2:4:100

2.80

2.30

i

1.80

g n d a e R y t i s n e D

1.30

0.80

0.30

1

2

3

4

6

10

7

9

12

13

14

15

16

17

18

19

5 11 8 Steps 1/2 stops .15 density units

Cyan

Magenta

Yellow

B & W

Chart 4-1 Film Density Readings

R E A D I N G S O N A D E N S I T O M E T E R

D en si ty i s th e measu r e of l i gh t wh i ch p asse s th r ou gh th e

n egati ve . Th i s i s kn own as tr an smi ssi on den si t y. L i gh t

r efl ecti n g fr om pr i n ted mat er i al i s kn o wn as r efl ec ted den si t y .

Th e den si to meter gi ves se t val u es to tr an smi tte d an d r efl ected

l i gh t . Th i s se t o f val u es al l o ws a c on si st en t co mpar i son for

both th e fi l m an d th e r esu l ti n g p r i n ts . D en si ty r an ge r efer s to

measu r i n g th e th i n n est an d th e den sest par t of th e n ega ti ve;

th e di ffer en ce bet ween i s th e den si ty r an ge.

5 1

Ch ar t 4 -2 demon str ates th e di ffe r en ce th e devel o per s made on

th e fi l m an d cor r espon di n g effect on th e pr i n t.

Film Print Comparison

3

2.5

2

1.5

e g n a R y t i s n e D

1

0.5

0

PMK Developer Rodinal Developer

FP4film FP4Print FP5 Film FP5 Print Forte Film Forte Print Foma film Foma print

Chart 4-2 Film Print Comparison

E N L A R G I N G N E G A T I V E S I N T H E D A R K R O O M

For con tact pr i n t i n g, 3 5 mm an d medi u m for mat 1 2 0 r ol l fi l ms

mu st b e en l ar ged to th e de si r ed pr i n t si z e. Th i s was ach i eved

by mean s of i n ter -n egati ve s wh i ch i s a t wo ste p pr oce ss or

r ever se pr ocessi n g , a on e st ep pr ocess . In ter -n ega ti v es ar e

cr eated by ma ki n g a po si ti ve f i l m to th e de si r ed si z e an d

con tact pr i n ti n g th e po si ti ve on to fi l m to cr eate a n egati ve .

Th ese mat er i al s wer e ex pen si ve a n d n ot r eadi l y avai l abl e .

Th e or th o fi l m an d l i th fi l m ar e h i gh con tr ast so di l u ted paper

devel oper s wer e u sed t o l o wer t h e con tr ast. A l l wer e ex p osed

an d pr ocesse d u n der a r ed safe l i gh t.

5 2

FIL M S TE S TE D :

I L F O R D O R T H O P L U S F I L M Th e po s i ti ve was pr oc esse d i n o

K odak S ol ectol 1 : 2. Th e n egati ve wa s pr oces sed i n both

PM K an d S el ectr ol an d compar ed. A l th ou gh b oth

pr ovi ded r eason abl e ton al r an ge s th e PM K pr oved mor e

su cces sfu l . E ven so a l o ss of con t r ast was appar en t wh en

compar i n g th e or i gi n al fi l m .

o B E R G G E R O R T H O C H R O M A T I C B PFB –1 8 F I L M . Th e posi ti ve was

pr ocess ed i n A gfa Nu etol . The n egati ve test s wer e

pr ocess ed i n both PM K an d A gfa Nu etol . Compar i son s

pr oved agai n th at th e PM K pr ovi d ed th e be tter r esu l t bu t

sti l l some l o ss of c on tr ast wa s ob ser ved .

o M A C O G E N I U S F I L M Th i s i s a ver y h i gh con tr ast fi l m so

di l u ted paper devel op er wa s u se d to l o wer th e con tr a st.

Th e posi ti v e was p r oces sed i n d i l u ted paper devel o per .

B y adju sti n g th e str en gth of th e devel oper th e con tr ast

wa s c on tr ol l ed . Th e con tr ast of t h i s fi l m c ompr e ssed th e

ton al r an ge.

o P H O T O C H E M R E V E R S E P R O C E S S I N G Il for d Oth o Pl u s an d M aco

Gen i u s fi l m wer e t este d , n ei th e r wer e su cc essfu l . Th e

Il for d was qu i te fl at i n ton es an d th e M aco fi l m di d n ot

r espon d wel l to th e ch emi cal s , bl each i n g th e si l ver fr om

th e fi l m.

D I G I T A L N E G A T I V E S

B on d Col ou r I magi n g, a pr ofe ssi on al ph otogr aph i c l ab or ator y ,

scan n ed th e 8 x 1 0 n egati ve at 40 0ppi gi vi n g a good qu al i ty fi l e

at 3 6 M B. Th i s was u sed as t h e con tr ol n egati ve for th e

fol l o wi n g secti on of th i s r esear ch .

D i gi tal n egati ves i n cl u de In kjet n egati ves fr om di gi tal fi l es

an d an al ogu e n egati ves fr om di gi tal fi l es. Th ese i n cl u de

i n kjet, i mage set ter or K odak D u r acl ear ™ pr ovi di n g bl ack an d

wh i te or c ol ou r n egati ve s. Th e c ol ou r n egati ves ar e kn o wn as

spectr al n egati ves.

5 3

S P E C T R A L N E G A T I V E S

Th i s i s a ter m u sed to descr i b e fi l m wh i ch u ses col ou r to

tr an smi t or bl ock di ffer en t l i gh t wav el en gth s r each i n g l i gh t

sen si ti z ed pap er .

Th e spe ctr al n egati ve wor ks on th e sa me pr i n ci pl e. Col ou r s

con tr ol th e ton al r an ge b y th e qu al i ty an d qu an ti ty o f l i gh t

r each i n g th e l i gh t sen si ti ve paper . A l th ou gh th e col ou r dye on

fi l m can act as a den si t y , bl o cki n g l i gh t si mi l ar to si l ver

par ti cl es i n an al ogu e fi l m, i t do es n ot h ave th e sa me su btl e

ton al gr ad ati on s wh i ch tr adi ti on al an al ogu e bl ack an d wh i te

fi l m offer s. Th i s i s sh o wn t o be mor e pr obl emati c i n

I N K J E T N E G A T I V E S F R O M D I G I T A L F I L E S

h i gh l i gh ts an d sh ado w r egi on s.

Th er e ar e n u mer ou s appr oach es to maki n g di gi tal n egati ve s.

M ar k Nel son ‟ s P r ec i si on Di gi ta l N ega ti ves sy stem em po wer s th e

r eader to cu s tomi se th ei r c ompu ter syst em , t o cr eate

n egati ves i n a n u mber of ou tpu t mod es th at wi l l su i t

par ti cu l ar pr ocess e s. U si n g r ed i n k to con tr ol th e ex p osu r e

wa s favou r ed by D an B u r kh ol der (B u r kh ol der , 19 99 ) . A l th ou gh

th er e wa s s ome su cce ss gen er al l y i t i n cr ease d th e con tr as t ,

cu r bi n g th e ton al r an ge.

It was fou n d th at pi gmen t i n ks an d dye -base d i n ks i n i n kjet

pr i n ter s made a c on si der abl e di ffer en ce to th e n egati v es ‟

den si ty an d ton al r an ge. Gen er al l y dye ba sed i n k s pr odu ce a

wi d er gamu t of col ou r an d a h i g h er r esol u ti on . Th e i n k si t s i n

th e str u ctu r e of th e fi l m. Th e pi gmen t i n k si ts on th e su r face

of th e fi l m . Th e dye -base d i n ks abi l i ty to bl o ck UV l i gh t i s

gr eater th an th e pi g men t base d i n ks ( Nel son , 2 0 0 4 ) . Th e

pi gmen t i n ks r equ i r ed con si der abl e adju stmen t to cr eate th e

same den s i ty an d con tr ast a s th e dye base d i n ks.

Th e type of i n kjet fi l m var i ed fr om cl ear to opaqu e. D i ffer en t

fi l m i s pr odu ced to a ccept pi g men t i n k an d dy e bas ed i n k s.

Tests wer e car r i ed ou t to sel ec t th e bes t r esu l ts. Th e dye

5 4

based i n k on A gfa Copy Jet wa s r e l ati vel y i n ex pen si ve,

avai l abl e l ocal l y an d for tu n atel y pr ovi ded th e better r esu l ts.

In kjet bl ack an d wh i te n egati ve s . Th ese fai l ed t o pr ovi de o

su ffi ci en t den si ty .

In kjet s pectr al n egati ve s . Th es e pr ovi ded th e b est of al l o

th e di gi tal n egati ve s. A s th e ou t p u t was fa st an d easy on

an i n kjet pr i n ter , n u mer ou s te st s cou l d b e car r i ed ou t.

Th e col ou r s th at pr ovi d e th e gr eatest t on al r an ge

ach i eved a r esu l t si mi l ar to th e su cces sfu l FP4 fi l m an d

PK M devel oper as sh o wn i n Fi gu r e 4 -2 .

i n kjet n egati ves . E ven t h ou gh th e fi n e paper o Paper

tested h ad mi n i mal tex tu r e i t affect ed th e pr i n t den si ty

an d th e paper cu r bed th e t on al r an ge wh i l e th e tex tu r e

soften ed th e i m age acu tan ce.

Figure 4-2 PMK Tones in Digital Negatives

In an al ogu e pr i n ti n g th e emu l si on si de of th e fi l m i s pl aced on

th e l i gh t sen si ti sed si de of th e p aper . Th i s r u l e sti l l ap pl i e s i n

i n kjet n egati ves .

5 5

A N A L O G U E N E G A T I V E S F R O M D I G I T A L F I L E S

D i gi tal fi l es wer e cr eated fr om t h e scan n ed con tr ol n egati ve.

B oth of th e fol l o wi n g n egati ve s wer e cr eat ed by ex p osi n g th e

di gi tal fi l e by l aser on to l i gh t sen si ti ve mater i al . Th i s mater i al

wa s th en pr oces sed b y de vel opi n g i n a tr adi ti on al " wet" fi l m

pr ocess or .

o K O D A K D U R A C L E A R ™ S P E C T R A L N E G A T I V E . Th i s col ou r fi l m i s

man u factu r ed for adver ti si n g l i g h t box es. Its cl ear fi l m

base made i t su i tabl e f or spec tr al n egati ves. V ar i ou s

tests wer e car r i ed ou t u si n g di f fer en t col ou r s . Th e i n -

bu i l t UV pr otecti on sl o we d th e ex posu r e ti mes

con si der abl y i n a UV l i gh t box . H owe ver th i s wa s

r eason abl y su cces sfu l i n pr odu ci n g th e ton al r an ge

u si n g su n l i gh t . Th i s i mpr oved th e ex posu r e ti me s o wi n g

to th e tr an smi s si on of l i gh t - wa ves i n th e vi si bl e

spectr u m. Th i s i s i l l u str ated i n Ch ar t 4 -3 . Th i s fi l m i s

qu i te ex pen si ve , h o wever B on d Col ou r I magi n g L ab

su bsi di se d th e cost f or th i s r esear ch .

I M A G E S E T T E R F I L M F R O M T H E S C A N N E D N E G A T I V E . Th i s ou tpu t i s o

bl ack an d wh i te an d th e c ost of th i s fi l m i s r eason abl e.

Nu mer ou s te sts wer e car r i ed o u t an d th e var i ou s d ot

scr een s, sp ot ty pes an d an gl es cr eated var yi n g col ou r s

wi th th e sal t pr i n t. Th e ou tcome fr om th e pr i n ts was n ot

as pr omi si n g as oth er meth o d s an d th e testi n g wa s

aban don ed. H o wever i t di d r ai se qu es ti on s wh y th e

space an d an gl e s of th e dots a ff ected th e c ol ou r of th e

pr i n ts test ed.

5 6

Figure 4-3 Spectral Negatives

Th e di ffer en t col ou r tests du r i n g th e ex pl or ati on of th e

spectr al n egati ves wi th th e ou tpu t on i n kjet an d K odak

D u r a cl ear ™ fi l m ar e demon str ated i n Fi gu r e 4 -3 . In th e top

r i gh t cor n er th e di ffer en t squ ar es of col ou r assi st ed i n fi n d i n g

th e col ou r s th at wou l d pr ovi de th e max i mu m an d mi n i mu m

den si ty i n th e pr i n t.

Ch ar t 4 -3 i l l u str ates th e tr an s mi s si on of a n u mber of th e fi l m s

tested. Th e r eadi n gs wer e ta ken on th e cl ear par t of th e fi l m

wi th ex cep ti on of „F P4 S i l ver Tr an smi ssi on %‟ . Th i s was ta ken

i n th e D -max of th e si l ver . Th e r esu l ti n g sampl es wer e

5 7

acqu i r ed u si n g a Car y 5 0 UV S pectr oph oto meter at th e

Ul tr avi ol et R adi ati on S ecti on of A R PA NS A .

Film Transmission

100

90

80

70

60

% n o i s s i

50

m s n a r T

40

30

20

10

0 3 4

0 0 2

0 0 3

5 1 3

0 3 3

0 5 3

0 7 3

0 9 3

0 1 4

0 5 4

0 5 5

0 5 6

0 5 7

0

FP4 Silver

FP4 Clear

Kodak Durotrans™

Agfa CopyJet

Pictorico %

Imagesetter %

Lith %

Wavelength

Chart 4-3 Film Transmission

In vesti gat i n g th e t on e r epr odu cti on of th e sal t pr i n t wa s ti me

con su mi n g. E ach n egati ve type wa s fou n d to h ave n u mer ou s

var i ati on s an d pr obl e ms. Th e t i me sp en t on th e n egati ve,

5 8

especi al l y th e di gi tal as pect , be came di s pr opor ti on ate t o th e

en ti r ety of th i s r esear ch paper . A l th ou gh a gr eat deal mor e

ex pl or ati on cou l d be car r i ed ou t, th e r esu l ts at th i s poi n t wer e

fel t to be r eason abl y con cl u si ve.

Th e fi l m n egati ve offer s th e gr eatest ton al r an ge, pr ovi di n g

su btl eti es o f ton e s th at th e di gi ta l n egati ve cou l d n ot pr odu ce.

Th e con jec tu r e was d ots maki n g u p th e i n kjet n egati ve ar e at

on e l evel bu t th e si l ver an al ogu e n egati ve pr ovi des a gr adati on

of ton es . A ddi ti on al l y , a r el i ef o f di ffer en t l evel s i n th e fi l m

emu l si on o ffer s fu r th er di men si o n s. PM K devel oper f or m ed th e

gr eatest r el i ef i n th e fi l m emu l si on .

Th e su cc essfu l sal ted pap er pr i n t r equ i r es a n egati ve wi th a

l on g ton al r an ge an d su ffi ci ent den si ty for en ou gh si l ver

ch l or i de to ch an ge i n to i mage maki n g metal l i c si l ver du r i n g

ex posu r e . E x ten si ve testi n g pr oved th at Il for d FP4 n egati ves

pr ocess ed i n th e dou bl e str en gt h PM K devel oper pr ovi de d an

ex cel l en t con ti n u ou s ton e , an d pr odu ced th e ex tr a den si ty

desi r abl e for sal t pr i n t i n g. Th e i n kjet n egati ve s wi th s i mi l ar

col ou r s to th e FP4 / PM K n egati ve pr oved to su r pas s a n u mber

of oth er types of an al ogu e fi l m n egati ves tes ted.

Negati ve s wi th i n adequ ate ton al r an ges an d den si ty f ai l e d to

pr odu ce qu al i ty sal t pr i n t s.

Hi gh con tr ast n egati ves ar e often qu oted i n tex t (James, 2 0 0 2 )

(Webb an d R eed, 2 0 0 0 ) as a basi c r equ i r emen t for th e

su cces sfu l sal t pr i n t. A l o w con t r ast n egati ve pr odu ce s a fl at

pr i n t bu t h i gh con tr ast n egati v e s r esu l t ed i n h ar sh „con tr ast y ‟

pr i n ts l osi n g detai l i n th e sh a do ws an d / or th e h i gh l i gh ts. Th e

l on g ton al r an ge of sal t pr i n ts pr ovi des ex cepti on al separ ati on

i n th e h i gh l i gh ts an d r ec or ds mi d ton e s par ti cu l ar l y wel l .

Ho wever s h ado ws l ack th e sa me degr ee of separ ati on an d may

l ack det ai l . A n egati ve wi th a h i gh per cen tage of sh a do w ar ea

cau se s an i mage to a ppear fl at , s o ex po si n g for th e sh ado ws i s

cr i ti cal . Th i s i s wh en th e sal t pr i n ts sel f -mas ki n g abi l i ty can

be u ti l i sed to max i mi s e th e ton al r an ge.

5 9

C h a p t e r 5 E X P O S I N G T H E P R I N T

A cti n i c i s th e l i gh t th at cau se s ch emi cal s to co mbi n e an d

decom pos e . S al t pr i n ts r el y on th i s en er gy as i t i s r i ch i n u l tr a

vi ol et an d bl u e r ays to cr eat e a ch emi cal r eacti on . Th e su n or

i ts al ter n ati ves (l a mp s or tu be s th at emi t UV l i gh t ) pr ovi de

th i s en er gy .

Wh i l e ex posi n g n egati ve s on th e sen si ti z ed paper , th e i mage

can be obser ved as i t appear s. Th i s ch apter i n vesti gates h o w

th e col ou r an d c on tr ast of th e pr i n t ar e affected by ex p osu r e.

Th er e ar e con tr ol s over th e i nten si ty of th e l i gh t an d th e

l en gth of ex posu r e wh i ch affe ct th e col ou r an d den si ty of th e

fi n al pr i n t.

Th e UV l i gh t affect s th e si l ver ch l or i de r el easi n g ver y s mal l

si l ver par ti cl es . Wh en si l v er i s i n ex cess, th e si l ver h al i de

car r i es th e ex ces s si l ver i on s abs or bed on to th e paper su r face

(War e, 1 99 4 ) .

Th e fol l o wi n g var i abl es wer e ex pl or ed .

l evel s of UV an d visi bl e l i gh t , an d the o V ar yi n g

di ffer en ces th ey ma y gen er ate .

o Ti me of th e day an d t i me of th e y ear .

o Hu mi di ty an d ambi en t t emper atu r e .

o D i r ect su n l i gh t (cr eates l ess con t r ast as th e ex po su r e i s

faster ).

In di r ect su n l i gh t an d cl ou d cove r ( i n cr eases c on tr ast a s o

th e ex posu r e i s sl o wer ) .

S I L V E R C H L O R I D E S E N S I T I V I T Y T O U V A N D V I S I B L E S P E C T R U M

It wa s establ i sh ed th r ou gh tes ti n g th e gl ass u sed i n the

ex posu r e fr ames bl o cked 1 0 0 % of wave l en gth s fr o m 3 3 0

n an ometr es an d bel o w. T h e l i gh t th at i s of i n ter est for th e sal t

6 0

pr i n t i s fr om 3 3 0 n m i n th e u l tr a vi ol et r egi on an d vi si bl e l i gh t

u p to 6 5 0 n m.

A l an E l l i ot advi sed by emai l 2 9 t h of M ar c h 2 0 0 7 h e h ad

i n vesti gat ed th e spec tr al sen si ti vi ty of si l ver i odi de . A n

ex per i men t wi th a smal l n eon l aser at 6 5 0 n m an d a

dagu er r eotype pl ate s en si ti sed wi th i odi n e sh o wed th e

sen si ti vi ty of si l ver i odi de ex t en ded to at l east 6 5 0 n m.

A l th ou gh sen si ti vi ty wa s ver y l o w at th at wavel en gth i t

defi n i tel y wa s n ot z er o. Th i s en cou r aged th e i n ves ti gati on of

si l ver ch l or i de ‟ s sen si ti vi t y u p to th e 6 5 0n m r egi on .

D u r i n g th e mi d par t of th e day th e su n i s i n a mor e dir ect l i n e

to th e ear th an d th er efor e th e r e i s mor e UV pen etr ati on .

Testi n g for th e var i ou s sp ectr u m cu t- ou t fi l ter s t ook pl ace

bet ween 1 2 . 0 0 h ou r s an d 1 4 . 3 0 hou r s at D e -i on i si n g R adi ati on

B r an ch of th e A u str al i an R adi ati on Pr otecti on an d Nu cl ear

S afety A gen cy . Th e fi l ter s teste d r an ge d fr om 3 0 5 n m to 6 4 5n m

as sh o wn i n Ch ar t 5 -2 .

Figure 5-1 Cut- off Filter Tests

6 1

Silver Chloride Sensitivity

1.80

1.60

1.40

1.00

1.20

0.80

y t i s n e D

0.60

0.40

0.20

l

5 9 3 G G

5 3 4 G G

5 7 3 G G

5 8 3 G G

0 0 4 G G

0 2 4 G G

5 5 4 G G

5 9 4 G G

0 3 5 G O

0 7 5 G O

0 1 6 G O

5 4 6 G O

o r t n o C

5 0 3 G W

0 2 3 G W

5 4 3 G W

0 6 3 G W

e s a B r e p a P

0.00

Cutoff Filters Formulas

NaCl + Gel Arrowroot

NaCl NH4Cl + GEL +Sodiun citrate Albumen

Chart 5-1 Silver Chloride Sensitivity

Cut-Off Filters

100.00

90.00

80.00

70.00

)

60.00

%

50.00

i

40.00

i

30.00

20.00

( n o s s m s n a r T

10.00

0.00

200 400 600 800 1000

WG305 GG400

WG320 GG420

Wave length WG360 GG455

WG345 GG435

GG385 GG495

GG395 OG530

Chart 5-2 Cut-off Filters

6 2

Th e test i n di cated pe ak sen si ti v i ty of si l ver ch l or i de i s fr om

3 6 0 n m to 3 8 5n m. Ho wever as sh o wn i n Ch ar t 5 -1 an d Fi gu r e 5 -

1 th er e i s sti l l str on g sen si ti vi ty u n der 3 6 0 n m. A bove 3 85 n m

sh o ws a gr adu al decl i n e an d at 4 5 5 n m th e sen si ti vi ty dr ops

r api dl y. S u bstan ti al l y wea ker acti vi ty i s appar en t to 6 4 5 n m.

Th e cu t of f fi l ter s avai l abl e a t th e D e-i on i si n g R adi ati on

B r an ch of th e A u str al i an R adi ati on Pr otec ti on an d Nu cl ear

S afety A gen cy st oppe d at 6 5 0 n m, h owever , an assu mp ti on th at

sen si ti vi ty c ou l d ex ten d beyon d 6 5 0 n m wou l d be r eason abl e .

Th e tests c on cl u ded th e gr eates t effect of l i gh t on th e sal t

pr i n t peaks at abou t 3 8 0 n m (n an ometr es) de pen di n g on th e

for mu l a an d bi n der , bu t vi si bl e l i gh t u p to 6 5 0 n m wi l l r edu ce

si l ver ch l or i de to metal l i c si l ver . S en si ti v i ty at th e h i gh er en d

of th e spec tr u m i s ver y l o w bu t some a cti vi ty of th e si l ver

ch l or i de i s sti l l appar en t .

Th e ambi en t tem per atu r e a ffect s sen si ti vi ty of th e ex posi n g

pr i n t wi th mu ch sl o wer r edu c ti o n of si l ver t aki n g pl ac e b el o w

5 ° C. Hi gh er temper atu r es al so cr eate h u mi di ty a s th e m oi stu r e

i s r el eased fr om th e pap er , i n cr easi n g th e sen si ti vi ty of th e

si l ver ch l or i de. Th i s wa s mor e n oti ceabl e wi th ar r owr o ot

bi n der s o wi n g t o th e am mon i a con ten t r e spon di n g mor e

r api dl y as th e h u mi di ty i n cr eases .

D i ffer en t types of n egati ves h ave di ffer en t UV an d vi si bl e

l i gh t spectr u m tr an smi s si on s. Th i s i s at tr i bu tabl e to th e

di ffer en t fi l m emu l si on s, deve l oper s, base f og an d i n ks

appl i ed to fi l m. Th e K odak D ur a cl ear ™ an d th e FP4 i n PMK

devel oper sh o wn i n Ch ar t 5 -3 ar e a good ex ampl e of th i s

di ffer en ce. A l so sh o wn i n Ch ar t 5 -3 th e FP4 an d th e A gfa Copy

Jet h ave si mi l ar tr an smi ssi on pr oper ti es th r ou gh th e fi l m D -

mi n base. A s si l ver or dye i s appl i ed th e tr an smi ssi on wi l l

ch an ge accor di n g to th e c ol o u r an d den si ty. Ch ar t 5 -3

compar e s FP4 D -mi n an d FP4 D -max i n di cates th e di ffer en ce i n

6 3

th e % of l i gh t tr an smi tted fr om t h e cl ear to th e den sest par t of

th e fi l m. (NB : Ch ar t 5 -3 i s si mi l ar to Ch ar t 4 -3 , th e data i s

r eu sed for easi er compar i s on i n th i s ch apter ).

.

Film Transmission

90

80

100

70

60

% n o i s s i

50

40

m s n a r T

30

20

10

0 9 3

0 0 2

0 0 3

5 1 3

0 3 3

0 5 3

0 7 3

0 1 4

0 3 4

0 5 4

0 5 5

0 5 6

0 5 7

0

Wavelength

FP4 PMK D-max FP4 PMK D-min

Kodak Duraclear D-min Agfa Copy Jet D-min

Chart 5-3 Film Transmission

Th e i n ten si ty of acti n i c l i gh t vari es wi th th e ti me of year an d

th e ti me of da y. A s th e an gl e of t h e su n to th e ear th i n cr ease s

th e con tr ast of th e pr i n t al so i n cr eases. D u r i n g th e wi n ter

mon t h s th e pr i n t ex p osu r e i s mor e gr adu al be cau se of th e

an gl e of th e su n an d th e l o wer ambi en t te mper atu r e s. Tu r n i n g

th e ex posi n g pr i n t awa y fr om th e su n i n cr ease s th e con tr ast.

A n ex posu r e fr ame, or con tact pri n t fr ame , i s made u p fr om 3

par ts; th e fr ame, g l ass an d a r emovabl e h i n ged back. Th e

fr ame h ol ds th e gl as s i n pl ace an d th e h i n ged bac k ap pl i es

pr essu r e on th e pa per an d n egati ve t o s top mo vemen t,

en su r i n g th ey r emai n i n r egi s tr ati on . Th e fi l m e mu l si on i s

6 4

pl aced agai n st th e sen si ti se d pap er emu l si on . Th e h i n ged back

al l ows i n spect i on of each si de o f th e pr i n t wi th l i ttl e r i sk of

der egi ster i n g th e fi l m an d paper .

Wh en th e ex posu r e fr ame i s pl aced i n th e su n l i gh t, th e

di ffer en ce i n temper atu r es bet we en th e cool gl as s an d th e

en cased sen si ti z ed pa per cr eat es a h u mi di t y ch a mber wi th i n a

fe w sec on ds . Th i s i n cr eases th e sen si ti vi ty of th e p aper an d

th e i mages app ear war m er i n col ou r .

E X P O S U R E T I M E S

Ju dgi n g th e r i gh t ex posu r e i s di f fi cu l t . Th e pr i n t mu st be over

ex posed b y abou t t wo stop s . F i x e r r emoves abou t t wo to th r ee

stop s of den si ty, bu t as th e i ma ge dr i es i t r egai n s on e to t wo

stop s i n den si ty. It i s t h e amou n t of si l ver ch l or i de con ver ted

to metal l i c si l ver ma kes th e den s i ty i n th e i mage.

Li g ht S o ur c e T i me

UV l i gh t box 1 5 to 3 0 mi n u tes

D i r ect s u n (n oon ) 1 0 to 2 0 mi n u tes

In di r ect su n (du l l day ) 3 0 mi n u tes to 3 h ou r s

Table 5-1 Exposure Times

In tabl e 5 -1 th e UV l i gh t box ex po su r e i s b ase d on a ban k of 1 7

Ph i l i ps A cti n i c B L 40 watt mer cu r y vapou r fl u or e scen ce UV

tu bes at a di stan c e of 2 0 cm fr o m th e pr i n t. Th ese t u bes e mi t

UV A fr om 4 0 0 to 3 2 0 n m pe aki n g r ou n d 3 7 0 to 3 8 0 n m . Th i s i s

sh o wn i n Ch ar t 5 -4 wi th a compar i son of Osr am 8 8 0

fl u or escen t tu bes u se d i n th e wor k r oom. UV fi l ter s for

fl or escen t tu be s i n di ca ted l i t tl e e ffect a s l i gh t bel o w 4 0 0 n m i s

n ot emi tted .

6 5

Fluorescent Tube Wavelength Frequency

λ

4200 4000 3800 3600 3400 3200 3000 2800 2600 2400 2200 2000 1800 1600 1400 1200 1000 800 600 400 200 0

0 3 2

0 5 4

0 6 6

0 0 2

0 6 2

0 9 2

0 3 3

0 6 3

0 9 3

0 2 4

0 8 4

0 1 5

0 4 5

0 7 5

0 0 6

0 3 6

0 9 6

0 0 8

Wavelengths

Osram880 Osram 880 with UV Filter Philips - 40W

Chart 5-4 UV Tube Wavelenghts

B y com par i n g C h ar t 5 -1 , Ch ar t 5 -2 an d Ch ar t 5 -3 th e si l ver

ch l or i de pr i n t ex posed i n th e U V l i gh t box on l y r ecei ves th e

wa ves of pea k sen si ti vi t y an d t h i s mean s th e n egati ves ar e

on l y tr an smi tti n g a smal l por ti on of th e possi bl e spectr u m.

Th e ex posu r e ti mes ar e de pen den t on a n u mber of var i abl es:

1 . Negati ve den si t y an d fi l m type .

2 . B i n der type ( ar r owr oot i s fast er th an al bu men du e to th e accel er ati n g effect of a mmon i a i n th e sol u ti on ) .

3 . A ddi ti ves (pota ssi u m di ch r omat e wi l l i n cr ease ex po su r e ti me, sodi u m ci tr ate decr ease s ex posu r e ti me ).

4 . M eth od of ex posu r e (su n l i gh t or con tr ol l ed UV l i gh t box )

6 6

Tr an smi ssi on S tep wedge s

Tr an smi ssi on ste p wedge s as si s t ed ton al r an ge co mpar i son s

agai n st n egati ves. B y ex posi n g th e step wedge besi de th e

n egati ve h el p ed t o i n di cate th e ton al r an ge i n th e ex pos ed

pr i n t, th u s assi st i n g i n cal cu l ati n g fu tu r e ex posu r es. Th e step

we dge wa s tr eated a s fu l l y ex po s ed wh en th e fi r st st ep wa s th e

same col ou r as th e ex p osed pap er ou tsi de th e n egati ve ar ea.

Th i s wa s ju s t bef or e br on z i n g occu r r ed. Th i s h el p ed to

deter mi n e :

ton al scal e of th e ex po sed paper . Th i s wa s o Th e

i n di cated by th e n u mber of se par ate step s vi si bl e.

If th e n egati v e h a d th e sa me to n al scal es as th e st ep o

we dge.

Tests wer e ma de u si n g th e var i o u s n atu r al den si ty fi l ter s. A s

th ese sl o w th e ex po su r e ti mes i t wa s ex pecte d th at an i n cr ease

of con tr ast wou l d be th e r esu l t. Th i s di d n ot occu r . R esear ch

establ i sh ed some n eu tr al den si ty sh eet fi l m u s ed dye s to

absor b th e l i gh t an d s ome gl ass fi l ter s i n cl u de d car bon wh i ch

al so fi l ter s di ffer en t wav e l en gth s bu t on l y i n th e vi si bl e l i gh t

spectr u m.

R E C I P R O C I T Y F A I L U R E

S l ower ex po su r e s i n cr ease th e co n tr ast of th e i mage wh i l e fast

ex posu r es d ecr ease th e con tr as t . Th e ex tr emes of ei th er of

th ese wi l l cau se r eci pr oci ty fai l u r e.

Hi gh i n ten si ty r eci pr oci ty fai l u re can occu r i f th e i mage i s

ex posed di r ectl y to h i gh UV co n ten t i n br i gh t su n l i gh t. Th e

ph oto l ysi s acti vi ty decr ease s an d th e sh ado ws wi l l n ot pr i n t as

dar k as l on ger ex posu r es . Th e l oss of th e dar kn ess i n th e

sh ado ws fl atten s th e ton al r an ge an d decr eases th e c on tr ast.

.

6 7

S E L F M A S K I N G

Th e sal t pr i n t „sel f - mask s‟ as i t i s ex posed to l i gh t . Th e

r edu ced me tal l i c si l ver bl o cks l i gh t to th e u n ex posed si l ver

bel o w. Th e sh ado w r egi on ( th e mor e tr an spar en t par t of th e

n egati ve) sl o ws th e r edu c ti o n of

si l ver . Th e pr i n ts l i gh ter ar eas (th e

den se par t of th e n ega ti ve) c on ti n u e

to ex po se n or mal l y. It i s t h i s sel f -

maski n g th at pr odu ces th e ex te n ded

ton al r an ge of th e sal t pr i n ts

(Cr awf or d , 1 9 7 9 ) . Th i s i s i l l u strated Figure 5-2 Self Masking i n fi gu r e 5 -2

B R O N Z I N G

B r on z i n g mean s th e par ti cl es of r edu ced metal l i c si l ver h ave

mi gr ated to th e su r face for mi n g a l ayer on th e su r face of th e

pr i n t. Th i s i s th e satu r ati on p oi n t wh er e th e pr i n t i s ov er

ex posed . D u r i n g ex posu r e th i s b r on z e gr een i sh br assy br o wn

sh een appe ar s on pr i n ts (R ei l l y, 1 9 80 ) . V er y l i gh t br on z i n g i n

th e i mage di sap pear ed du r i n g pr ocessi n g.

Fi gu r e 5 -3 i l lu str ates at di ffer en t mag n i fi cati on s h o w th e

si l ver par ti cl e s h ave mi gr ated t o th e su r face. Th e 1 s t i mage

sh o ws magn i fi cati on at 2 3 1 ti me s l i fe si z e , th e 2 n d i s at 1 3 5 1

ti mes l i fe si z e an d th e 3 r d at 3 6 1 ,1 8 0 ti mes l i fe si z e .

Figure 5-3 Bronzing Surface Detail

6 8

Paper fi br e str u ctu r e i s n or mal l y vi si bl e bu t wi th br on z i n g i t

appear s smo oth u n ti l th e h i gh er magn i fi cati on r eveal s th e

si l ver par ti cl es th at h ave been r ai sed to th e su r face .

Figure 5-4 Bronzing high Magnification

Fi gu r e 5 -4 magn i fi cati on at 1 0 1 , 69 1 ti mes l i fe si z e, i l l u str ates

th e var yi n g par ti cl e si z es fr om 2 0 n m to 1 5 1 n m. Th ese ar e

measu r ed on th e scr een du r i n g th e n an oS E M scan n i n g pr ocess.

Con ti n u i n g th e ex posu r e cr eate s a deep br on z i n g wh i ch

r emai n s i n th e i mage sh ado w r egi on s after pr oces si n g . Th i s

destr oy s th e pr i n t s sh ado w ton es . If a n egati v e h as c or r ect

den si ty an d b r on z i n g h as for m e d i n th e mar gi n s , th e pr i n t is

at i ts max i mu m den si ty. Th i s mean s ex po su r e can be

mon i tor ed b y vi e wi n g mar gi n s ou tsi de th e n egati ve ar ea

wi th ou t open i n g th e ex posu r e fr ame .

Wh en th e pr i n t i s ex posed to l i gh t :

o Th e si l ver ch l or i de di sa ss oci at es th e si l ver an d th e

ch l or i de, r el easi n g smal l par ti cl es of si l ver metal .

o S i mu l tan eou sl y fr ee ch l or i n e mol ecu l es ar e r el eased.

o Th e ch l or i n e absor ber s , compr i si n g of moi stu r e of th e paper fi br es an d ex ce ss si l ver n i tr ate , r eact wi th th e r el eased ch l or i n e for mi n g mor e s i l ver ch l or i de.

6 9

o Th e

l i gh t con ti n u es to br eak do wn th i s n e w si l ver ch l or i de cr eati n g mor e metal l i c si l ver , an d th e cycl e con ti n u es (War e, 1 9 9 4 ).

Wi th ou t l i gh t, spon tan e ou s r edu c ti on of me tal l i c si l ver cr eate s

a yel l ow c ol ou r . Th i s con si sts o f r edu ced metal l i c si l ver i n a

fi n el y di vi ded state (sl o w ex p osu r es i n cr ease con tr ast b y

cr eati n g fi n er si l ver ) , accel er ated by war m th an d h u mi di ty

(R ei l l y, 19 8 0 ). Wh en th e r edu cti on of si l ver co n ti n u ed th e

col ou r ch an ge d to r ed br o wn a n d after a per i od of mon th s ,

actu al l y h a d a br on z ed appear an ce .

Ti n y si l ver par ti cl e s c ombi n e for mi n g l ar ger par ti cl es

ch emi st s cal l col l oi dal . Th ey ab s or b so me wavel en gth s bu t ar e

n ot l ar ge en ou gh to absor b a l l wa vel en gth s of l i gh t. Th i s i s

depen dan t on th e i n dex o f r efr acti on of th e bi n der i n wh i ch

th ey ar e di sper sed. For ex am p l e , al bu men h as a di ffer en t

r efr acti on to gel ati n cr eati n g a di ffer en t col ou r .

Th e sen si ti vi ty of th e si l ver ch l or i de to th e vi si bl e s pectr u m

pr oved to be far m or e wi de -r an gi n g th an ex pected . Th e UV

l i gh t box Ph i l i ps A cti n i c BL 4 0 watt mer cu r y vapou r

fl u or escen ce mi r r or ed th e pea k sen si ti vi t y t o th e sol ar

spectr u m. Th i s ex pl ai n s th e po or ou tcome fr om fi l m wi th a

h i gh base fog or i n bu i l t UV fi l te r s su ch as K od ak D u r ocl ear ™

as i n su ffi ci en t l i gh t was tr an sm i tted at th e si l ver ch l or i des

peak sen si ti vi ty. Ho wever s u n l i gh t ex posu r es pr ovi d ed

en ou gh r adi ati on fr om th e vi si bl e spectr u m to cr eate i mages,

al th ou gh th e ex po su r es wer e 3 t o 5 ti me s l on ger wi th K oda k

D u r ocl ear ™. Fi n di n g h ow th e l on ger l i gh t - waves i n th e

spectr u m s pl ay a par t i n ex ten di n g th e ton al r an ge an d c ol ou r s

cal l s for possi bl e fu r th er r esear ch .

7 0

C h a p t e r 6 P R O C E S S I N G T H E P R I N T

Th e wash , t on i n g, fi x er an d fi n al wash i n g h a ve an effec t on

th e col ou r an d th e l i fe of th e pr i n t. A ccou n ts of t h e di ffer en t

ar eas of pr oces si n g con t ai n a n u mber o f con fl i c ti n g

statem en ts. Ti me was spen t te sti n g an d ch ecki n g var i ou s

r esou r ces to fi n d some accu r acy an d con si st en cy. M i ke War e,

(emai l 2 8 t h Ju n e 2 0 04 ) i n di cate d th e effect of th e 'Hyp o' fi x i n g

bath i s pr ofou n d i n modi fyi n g t h e col ou r of th e si l ver i mage .

He bel i eve d th i s i s mor e i mp or tan t th an th e par ti cl e si z e an d

su spect s i t ma y be du e to a mo n ol ayer (or mor e) o f su l ph i de

deposi t ed on th e su r face of th e si l ver n an o - par ti cl es, wh i ch

str on gl y mo di fi es th e ' su r face pl asma r es on an ce' effec ti n g th e

col ou r . He bel i eve s th i s „ su l ph i de ton i n g' i s r esp on si bl e for

mu ch of th e col ou r ph en ome n a . A s a r esu l t o f War e‟ s

statem en t a stu dy of r esi du al su l ph u r was i n cl u de d i n th e

an al ysi s.

F I R S T W A S H

Th e fi r st wa sh i s desi gn ed to r emove ex ces s s al ts of

u n ex posed si l ver ch l or i de an d si l ver n i tr ate. Th er e ar e man y

di scr epan ci es i n th i s ar ea . On e of th e r ecommen da ti on s i s to

pl ace th e pr i n ts i n a 5 % sol u ti on of so di u m ch l or i de an d

agi tate for 2 mi n u tes (Wal l and Jor dan , 1 97 5 ) . Ter r y K i n g

su ggests wash i n g i n pl ai n water f or two mi n u tes or u n ti l water

i s cl ear (B ar n i er , 20 0 0 ) . „„Wash f or sever al mi n u tes u n ti l . . . n o

fu r th er mi l ki n ess ” (Far ber , 19 9 8) . Ch r i stoph er James (Ja mes,

2 0 02 ) su ggests a sodi u m ch l or i d e bath for 3 0 secon d s an d a

fu r th er 2 0 mi n u tes of wa sh . No t wo bo ok s see m to co n cu r .

Th e E n cycl o paedi a of Ph otogr a ph y (J on es, 1 9 7 4 ) (or i gi n al

pu bl i cati on 1 8 7 9 ) su ggests a we ak s ol u ti on of sal t befor e

ton i n g to r emove si l ver sal t s.

7 1

M i ke War e ‟ s co mmu n i cati on by emai l ( 2 2 n d Febr u ar y 2 0 0 5 )

ex pl ai n ed th e ph en o men a of t h i s sal t ba th . “ It pr even t s

stai n i n g i n th e fi x er . Th e di l u te sodi u m ch l or i de s ol u t i on wi l l

n ot di ssol ve th e si l ver sal t s as th e sodi u m th i osu l fate d oes.

S ol u bl e si l ver i on s ar e fr o m ex ce ss si l ver n i tr ate i n sal t pr i n ts .

Th ese ar e ox i di si n g an d t en d to r eact wi th 'h ypo' u l ti matel y

cr eati n g si l ver su l ph i de . Th i s ca n cau se a yel l o w/ br o wn s tai n .

B efor e fi x i n g a sal t pr i n t wi th th i osu l ph ate i t i s i mpor tan t to

r emove th e fr ee sol u bl e si l ver i o n s . S odi u m ch l or i de does th i s

by pr eci pi tati n g si l ver ch l or i de , wh i ch i s n ot ox i di si n g . It th en

di ssol ve s i n th e th i osu l ph at e fi x er wi th n o su l ph i de

for mati on . ”

A n u mber of test s wer e con du ct ed an d i t was fou n d th at th e

i n cl u si on of sodi u m ch l or i de i n th e ser i es of th e fi r st wash es

el i mi n ated st ai n i n g. D u r i n g th e pr ocess c ol ou r ch an ges wer e

obser ved, t h e sal t s ol u ti on „bl e ach e d‟ th e pr i n t fr om a r i ch

deep br o wn t o a l i gh t or an ge / br o wn col ou r . Th ese wer e si mi l ar

to th e fi x i n g pr ocess ch an ges.

E x cess si l ver n i tr ate, si l ver ch l or ide an d sodi u m n i tr ate r etar d

th e ton i n g pr ocess; th i s fi r st bat h ser i es i n cl u di n g th e sodi u m

ch l or i de en su r ed th ei r r emoval . Th e te mper atu r e of th e water

wa s mai n tai n ed at 2 0 ° C to i n cr eas e th e speed of th e

di ssi pati on o f ex cess sal ts. Th e p r i n t a t 3 0° C i n th i s wash

dr i ed sl i gh tl y cool er i n col ou r .

T O N I N G

Ton i n g wi th gol d , pl ati n u m an d pal l adi u m n ot on l y i n ten si fi e s

th e i mage bu t al s o i n cr ease s th e l i fe s pan of th e pr i n t. Th e

mass of mi n u scu l e si l ver par ti cl es on th e paper su r face ar e

su scepti bl e to d estr u cti on i n ox i di z i n g an d su l ph ur i c

con di ti on s of a n or mal atmos ph e r e . Th e gol d sh i el d s th e si l ver

par ti cl es fr om ox i di z ati on for mi n g a comp ou n d th at i s mor e

r esi stan t to ox i di z ati on (War e, 2 0 06 . ) . Th e ton er s cr eate a

l i gh t sen si ti v e ch l or i de as a b y pr odu ct of t on i n g , th i s i s

r esol ved by fi x i n g after th e ton i n g (R ei l l y, 1 98 0 ) .

7 2

M u ch of th e cur r en t tex t on t on i n g pr esen ts con tr adi ctor y

i n for mati on an d i n c on si st en t fo r mu l as. R esear ch an d test i n g

ton i n g for mu l as easi l y sol ved man y of th ese pr obl ems.

Tex tbook s al so di ffer on th e impor tan ce of ton i n g (B ar n i er ,

2 0 00 ) h as n o men ti on of t on i n g , wh er eas (R ei l l y, 1 9 8 0 ) an d

(War e, 2 00 6 . ) di scu ss i n -depth t h e vi tal i mpor tan ce of ton i n g

sal t pr i n ts. Th e for mu l as for th e ton er s ar e se t ou t i n

A ppen di x 2 .

Th e ter ms su ch as “ don e by i n sp ecti on ” (R ei l l y, 1 9 8 0 ) “ ton e to

th e desi r ed col ou r , ” or “ wh en th e pr i n t ch an ged to your

sati sfacti on ” (Webb an d R eed, 2 0 00 ) ar e u sed to state th e

col ou r ch an ges du r i n g ton i n g . It i s i mpos si bl e to de tect th e

fi n al col ou r du r i n g ton i n g as man y ch an ge s i n col ou r take

pl ace befor e th e sal t pr i n t i s fi n a l l y dr y. Un l es s r i gor ou s te sts

h ave been car r i ed ou t n oti n g t y pe, str en gth an d ti me i n th e

ton e r , i t can be di ffi cu l t to r ep l i cate th e ton ed col ou r .

Th e type of bi n der an d th e pr i n t su r face make a di ffer en ce

wh en ton i n g. M an y of th e tex ts s u ggest th at al bu men r equ i r es

dou bl e th e amou n t of g ol d ch l or i de i n th e gol d ton i n g sol u ti on

(R ei l l y, 1 98 0 , Far ber , 19 98 ) . Thi s was fou n d to yel l o w th e

h i gh l i gh ts as i l l u str ated i n Fi g u r e 6 -1 4 . Ton er s for sal t

pr i n ti n g pr oved to be adequ ate for al bu men pr i n ti n g , an d i f

n ecessar y ex ten d i n g ton i n g ti me .

Ton i n g for mu l as asses sed i n cl u ded gol d bor ax , gol d sodi u m

acetate, t wo str en gth s of th i oc yan ate gol d t on er s, p l ati n u m

ton er an d a pal l adi u m ton er . S pl i t ton i n g u si n g t wo di ffer en t

ton er s an d h eat ton i n g w er e al so eval u ated.

Th i ocyan ate gol d ton e r s cr eate a mu ch cool er col ou r , sh ado w

r egi on s al most a ppear bl ack , mi d ton es pu r pl e bl u e an d th e

h i gh l i gh ts l aven der . Th i s i s d epen den t on th e pa per an d

for mu l as u sed. S ee Fi gu r es 6 -3 , 6-8 , an d 6 -1 8 .

Pl ati n u m ton er cr eate s a gr ey/ bro wn / bl ack ton e . A l th ou gh th e

same str en gth an d ti me i s su g gested for al bu men an d sal t

pr i n ts, i n testi n g th e al bu men h i gh l i gh ts tu r n ed yel l o w an d

7 3

th e pr i n t bl each e d back on e sto p (Fi gu r e 6 -1 5 ). For al bu men

th i s for mu l a i s better di l u ted by 5 0 per cen t. Gel ati n si z ed sal t

pr i n ts yel l o wed ver y sl i gh tl y i n h i gh l i gh ts an d th e pl ai n sal ted

paper h i gh l i gh ts r emai n ed wh i te.

Th e p al l adi u m ton er cr eate s a cool gr ey / br o wn bu t th e

str en gth of th e for mu l a r api dl y tu r n s th e al bu men h i gh l i gh t

ver y yel l o w (Fi gu r e 6 -1 6 ). In testi n g th e for mu l a was cu t back

to 2 5 per cen t an d th e pr i n t was l eft i n th e ton er for on e

mi n u te. Gel ati n si z ed sal t pr i n ts sh o wed sl i gh t yel l o wi n g i n

h i gh l i gh ts an d th e pl ai n sal ted paper h i gh l i gh ts r emai n ed

wh i te.

S pl i t ton i n g was car r i ed ou t by u si n g gol d bor ax ton i n g

fol l o wed by pl ati n u m t on i n g (Fi gu r e 6 -5 ) an d gold thiocyanate

toner followed by platinum toning (Figure 6-20). Wh en spl i t ton i n g ,

gol d ton er s mu st be u sed b ef or e th e aci di c pl ati n u m or

pal l adi u m ton er s. Th e aci d wi l l sl o w or stop th e acti vi ty of th e

al kal i n e gol d ton er s

Tex tbook s sta te ti m e i n th e ton er sh ou l d be: fr om 3 mi n u tes to

1 5 mi n u tes (R ei l l y, 1 9 8 0 ) , 5 to 1 0 mi n u tes (Far ber , 1 9 9 8 ) an d 6

mi n u tes to 1 2 mi n u tes (Web b an d R eed, 2 00 0 ) . Tests

demon s tr ate th at i n a fr esh ton er , 1 mi n u te to 2 mi n u tes i n

th e bath wi l l sh o w ch an ge s an d 3 mi n u tes to 1 0 mi n u tes

su bstan ti al l y ch an ge s th e pr i n t . Ho wever th i s de pen ds on th e

n u mber of pr i n ts th at h ave pr evi ou sl y been th r ou gh th e ton er

Th e test t on i n g bath s wer e at 2 0 ° C. 3 mi n u tes to 5 mi n u tes;

th i s appear ed to gi ve pr ot ecti on wi th s ome c ol ou r ch an ge.

A l l r eadi n g s i n Tabl e 6 -1 to 6 -3 wer e taken fr om step n u mber

1 1 i n th e ton i n g step wedge s.

7 4

Figure 6-1 Sodium Chloride – no Toner

Figure 6-2 Sodium Chloride –Gold Borax Toner

Figure 6-3 Sodium Chloride - Gold Thiocyanate

Figure 6-4 Sodium Chloride – Platinum

Figure 6-5 Sodium Chloride- Gold Borax and Platinum

Figure 6-6 Ammonium Chloride + Gelatin - No Toner

7 5

Figure 6-7 Ammonium Chloride + Gelatin - Gold Borax Toner

Figure 6-8 Ammonium Chloride + Gelatin - Gold Thiocyanate

Figure 6-9 Ammonium Chloride + Gelatin - Platinum Toner

Figure 6-10 Ammonium Chloride + Gelatin - Gold Borax and Platinum

Figure 6-11 Ammonium Chloride + Gelatin - Gold Acetate1

Figure 6-12 Ammonium Chloride + Gelatin - Palladium Toner

Figure 6-13 Albumen No Toner

7 6

Figure 6-14 Albumen Gold Borax Toned

Figure 6-15 Albumen Platinum Toned

Figure 6-16 Albumen Palladium Toned

Figure 6-17 Albumen Gold Acetate Toner

Figure 6-18 Albumen Gold Thiocyanate Toner

Figure 6-19 Albumen Gold Borax and Platinum Toned

Figure 6-20 Albumen Gold Thiocyanate and Platinum Toned

7 7

S o di um Chl o r i de L* a. b.

No ton er : Fi gu r e 6 -1 P anto ne ® S o l i d M att 4 0 75 m 4 0 1 9 1 7

Gol d B or ax Ton er : Fi gu r e 6 -2 4 1 1 m 3 9 6 5

7 5 40 m 4 6 1 -3 Gol d Th i ocyan at e Ton er : Fi gu r e 6 -3

Pl ati n u m Ton er Fi gu r e 6 -4 7 5 31 m 5 0 5 1 2

4 3 8 m 3 1 9 2 Gol d B or ax an d Pl ati n u m Ton er : Fi gu r e 6 -5

Chart 6-2 Sodium Chloride Toning

Ammo ni um Chl o r i de +Ge l ati n

No ton er : Fi gu r e 6 -6 7 5 18 m 4 0 1 1 1 0

Gol d B or ax Ton er : Fi gu r e 6 -7 1 1 m 4 2 4 7

Gol d Th i ocyan a te Ton er : 4 3 8 m 3 1 9 2 Fi gu r e 6 -8

Pl ati n u m Ton er : Fi gu r e 6 -9 7 5 33 m 2 8 5 1 1

7 5 05 m 4 5 1 1 2 4 Gol d B or ax & Pl ati n u m Ton er : Fi gu r e 6 -1 0

Gol d A cetate T on e r : Fi gu r e 6 -11 1 0 m 5 0 4 6

9 2 2 Pal l adi u m Ton er : Fi gu r e 6 -1 2 8 7 4 m 5 1

Chart 6-3 Ammonium Chloride and Gelatin

Al bume n

No ton er : Fi gu r e 6 -1 3 7 5 15 m 4 2 1 5 1 6

Gol d B or ax Ton er : Fi gu r e 6 -14 1 0 m 5 0 4 6

Pl ati n u m Ton er : Fi gu r e 6 -1 5 8 7 3 m 5 2 7 2 3

Pal l adi u m Ton er : Fi gu r e 6 -1 6 4 6 5 m 6 8 6 2 9

3 6 Gol d A cetate T on er : Fi gu r e 6 -17 9 m 5 5

8 0 21 m 5 4 1 0 1 1 Gol d Th i ocyan at e Ton er : Fi gu r e 6 -1 8

7 5 04 m 5 2 9 1 9 Gol d B or ax an d Pl ati n u m Ton er : Fi gu r e 6 -1 9

7 5 19 m 4 0 1 1 1 0 Gol d Th i ocyan a te an d Pl ati n u m Ton er : Fi gu r e 6 -2 0

Chart 6-1 Albumen Toning 7 8

Th e pr i n t col ou r i s sai d to be in fl u en ced by si z e, sh ape, th e

di stan ce b et ween th e si l ver par ti cl es an d th e of r efr acti on

l i gh t th ou gh th e medi u m i n wh i c h th ey ar e di sper se d . Th e gol d

ton i n g modi fi es th e i mage c ol o u r by ch an gi n g th e si z e an d

sh ape of th e si l ver par ti cl es . It r epl ac es si l ver ato ms wi th g ol d

atoms. Th i s en l ar gemen t of th e p ar ti cl es mak es th e i mage l o ok

cool er an d mor e n eu tr al i n to n e (War e, 2 0 0 6. ) . In al kal i n e

ton er s th e ato ms of g ol d r epl ac e on l y o n e of th e si l ver l eavi n g

a cool er col ou r wi th th e ton al r a n ge r emai n i n g i n tact (R ei l l y,

1 9 80 ) .

Heat ton i n g i s per for med after th e pr oces si n g an d wh en th e

pr i n t i s dr y. M an y su ggest ( Far ber , 1 99 8 , R ei l l y an d K en n edy,

1 9 84 , R ei l l y, 1 98 0 , James, 2 00 2 ) cover i n g th e pr i n t wi th br o wn

paper an d pr es si n g wi th a h ot i r on . Th i s d emon str ated

mi n i mal ch an ge . Ho wever a dr y mou n t h eat pr ess wh er e th e

pr i n t i s en cl osed made a su bsta n ti al di ffer en ce to th e col ou r .

Th e paper becam e c ompr e ssed an d si l ver par ti cl e s wer e dr a wn

to th e su r face by th e h eat an d h u mi di ty as sh o wn i n Fi gu r es 6 -

2 1 an d Fi gu r e 6 -2 2 .

Figure 6-21 Heat Toned High Magnification

7 9

Figure 6-22 Heat Toned

Th i s h eat an d h u mi di t y ca u s es th e pr i n t to co ol i n col ou r fr om

war m br o wn to bl u e br o wn . Th i s i s cl ear l y appar en t i n th e s tep

we dge i n fi gu r e 6 -2 3 . Th e l i ght i s r efl ecti n g off th e n o w

masse d par ti cl es. A l l paper s t est ed r espon de d by ch an gi n g to

cool er col ou r s i n var yi n g degr ees .

Figure 6-23 Result of Heat Toning

L * a. b.

Heat Ton ed: S h ado ws Pan ton e® S ol i d M att B l ack m 1 2 1 0

Un ton ed : S h ado ws 4 9 75 m 1 9 1 7 8

Heat Ton ed: M i d-t on es 7 4 97 m 4 7 0 1 6

Un ton ed : M i d-ton e s 7 5 04 m 5 2 9 1 9

Heat Ton ed: Hi gh l i gh ts 7 4 99 m 9 2 -1 1 4

Un ton ed : Hi gh l i g h ts 4 6 85 8 6 5 9

Table 6-1 Heat Toning

S el en i u m Ton i n g

Th i s was f ou n d be an u n sati sfact or y ton er for sal t or al bu m en

pr i n ts ei th er befor e or after fi x in g . Th e pr i n ts con stan tl y l oo k

bl each ed ou t. War e ex pl ai n s i t is a con sequ en ce of th e ti n y

par ti cl es ‟ l o w abs or bi n g po wer . Th e si l ver sel en i de an d si l ver

su l fi de bec ome se mi -tr an s par en t appear i n g a s a bl each ed

i mage (War e, 1 9 9 4 ).

8 0

T H E F I X

Th e pu r pose of fi x i n g i s t o r emove th e u n r edu ced si l ver

ch l or i de an d oth er l i gh t -sen si ti ve su bstan ces wh i ch ma y be

pr esen t , gi vi n g stabi l i ty to th e pr i n t

Fi x i n g th e i mage i s compl ex ; for l on g ter m stabi l i ty en ou gh

ti me mu st be al l o wed to di ssol v e th e u n ex posed si l ver wi th ou t

bl each i n g an d damag i n g th e qu al i ty of th e i mage.

R eady-m ade fi x er s wi l l di ssol v e th e si l ver sal ts . However th ese

com mer ci al l y man u fact u r ed fi x e r s , especi al l y aci d h ar den er

fi x er s, ar e n ot su i tabl e for sal t pr i n ts . Th e y bl each ou t th e

n an o-par ti cl es of si l ver , weaken i n g th e pr i n t s den si ty . Th i s i s

ex acer bated wh er e gel ati n i s u se d i n th e co ati n g or th e si z i n g

of th e pr i n t.

A ddi n g 0 . 2 % of sodi u m car bon ate to a 1 0 % fi x er of sodi u m

th i osu l fate mak es a sl i gh tl y al k a l i n e fi x er bath stoppi n g aci ds

fr om decom posi n g th e sodi u m th i osu l fate an d l i ber ati ng

su l ph u r . A ci d fi x er bath s cau se b l each i n g i n th e h i gh l i gh ts an d

mi d ton es b y attac ki n g th e fi n e si l ver metal l i c par ti cl es

(R ei l l y, 1 98 0 ) .

Th e fi x er sh ou l d be made ju st befor e u s e t o mi n i mi se

decom posi ti on . S odi u m th i osu l fa te i n i ts dr y for m i s r el ati vel y

stabl e. It i s u n stabl e wh en di ss ol ved i n water , de com posi n g to

sodi u m su l ph i te an d el e men tal su l ph u r (R ei l l y, 1 98 0 ) .

D ar k mottl e d s tai n s i n di cate d th e fi x er i s ex h au sted, wh er e as

yel l o wi n g of th e pr i n t or yel l o w stai n s i n di c ated th e p r i n t i s

l eft too l on g i n fi x er .

T wo fi x er bath s ar e es sen ti al as th i osu l fat e i on s mu st b e

pr esen t i n ex cess or i n sol u bl e co mpl ex es ar e for med wh i ch ar e

on l y sol u bl e i n fr esh th i osu l fate .

1 . In th e fi r st bath si l ver th i osu l fate compl ex e s for m .

2 . In th e secon d bath i n sol u bl e co m pl ex es a r e r emoved .

Pr i n ti n g ou t paper s after fi x i n g become yel l o w/ r ed/ br own i n

col ou r . R ei l l y (1 9 8 0 ) su ggests th e s i l ver par ti cl es pack cl os e l y

8 1

togeth er as th e fi x er di ssol ves u n r edu ced si l ver ch l or i de.

A n oth er th eor y su ggest th e yel l owi n g of th e pr i n t i n th e fi x er

i s du e t o th e tr an sf or mati on of t h e si l ver to a l o wer r efr acti ve

po wer so th e abs or pti on i s mov ed to th e sh or t wave l en gth s

(Cl er c, 1 9 4 4 ). Th e secon d th eor y i s mor e pr oba bl e as th e si l ver

par ti cl es adh er e to th e paper fi br es, th e paper s d o con tr act

an d ex pan d bu t th i s yel l o w col o u r wou l d be a ppar en t i n th e

fi r st con tact wi th th e water i f R ei l l y‟ s th eor y was cor r ect.

T H E C L E A R I N G A G E N T

Th e u n pr otected paper base of t h e sal ted paper an d al bu men

pr i n ts al l ows a gr eater absor pti o n of sodi u m th i osu l fat e th an

mass pr odu ced devel opi n g ou t paper s. For th i s r ea son i t i s

al most i mp os si bl e to r emo ve al l th e tr aces of fi x er s wi th ju st

wa ter . A wash i n g ai d i s th er efor e essen ti al for m or e co mpl ete

r emoval of dama gi n g si l ver -th i os u l fate compl ex e s.

T H E F I N A L W A S H

In su ffi ci en t wash i n g i s sti l l th e mai n cau se of de ter i or a ti on of

sal t pr i n ts . Fa ctor s fou n d f or c r i ti cal wa sh i n g ar e a gi tati on

an d water r epl a cemen t du r i n g t h e wash . A l s o mai n tai n i n g a

temper atu r e above 2 0 ° C. an d al l owi n g t i m e for th e fi x er to

di ssi pate ou t of th e paper i n to th e wa ter .

D epen di n g on th e th i ckn e ss of th e paper , th e pr i n ts sh ou l d

r ecei ve at l east a 3 0 - mi n u te wa sh . Heavi er paper s an d mor e

den sel y coa ted pap er s su ch as al bu men wi l l r equ i r e l on ger

wa sh i n g ti mes th an pl ai n sal t ed pr i n ts (L avedr i n e, 2 00 3 ).

Testi n g fou n d th at 2 h ou r was n ot adequ ate i n r emovi n g al l

tr aces of su l ph u r for th e fi x er .

8 2

TE S TS FOR R E S ID UA L S OD IUM THIOS UL FA TE

A r ch i val pr ocessi n g pr acti ces wer e adh er ed to du r i n g th e

var i ou s test s . Th e K odak Hyp o T est S ol u ti on HT1 a was u se d to

i den ti fy r esi du al sodi u m th i osu l fate. E ven th ou gh th e se test s

i n di cat ed n o r esi du al s odi u m th i osu l fate , th e E D A X i n di cated

oth er wi se. Th e al bu men an d star ch bi n der s gave th e h i gh est

r eadi n gs of su l ph u r . G el ati n h a s th e l o we st r eadi n g , bu t al l

i n di cated th e pr esen ce of su l ph u r . A l bu men i s per h aps

ex pected to r etai n so me su l ph u r attr i bu ted t o th e su l ph u r i n

th e egg wh i te.

E ach step of pr oces si n g th e pr i n t n ot on l y i n fl u en ces th e pr i n t

col ou r bu t al so i t s l i fe. Th e mo s t dr amati c ch an ge i n th e sal t

pr i n t col ou r came th r ou gh th e var i ou s ton i n g for mu l as.

8 3

C h a p t e r 7 D I S C U S S I O N

Wi l l i am Hen r y Fox Tal bot ‟ s or i gi n al sal t pr i n t for mu l a of a

sodi u m ch l or i de sol u ti on ( co m mon tabl e sal t) an d a si l ver

n i tr ate sol u ti on appear s si mp l e . Ho wever , si l ver n i tr ate

i n ter acts wi th n u mer ou s or gan i c an d i n or gan i c su bstan ces.

S tai n i n g or ch emi cal „foggi n g ‟ appear s i n th e pr in t u n l ess th e

paper , paper coa ti n g tool s an d t h e wa ter for th e for mu l as ar e

fr ee fr om an y con tami n ati n g mat t er .

Th e bi n der s su spen ded th e ch l o r i de sol u ti on an d acted as a

si z i n g agen t h ol di n g back si l ver ch l or i de sol u ti on s bei n g

absor b ed i n to th e paper fi br es. It i s th i s su b str ate or l ayer

wh i ch r efr acts l i gh t an d con sequ en tl y th e th i cker th e

su bstr ate th e war mer th e pr i n t col ou r . Th e war mth an d

acu tan ce of th e pr i n t can be c on tr ol l ed by th e a mou n t of

gel ati n si z i n g. A l th ou gh al bu men war m ed th e i ma ge col ou r an d

gave br i l l i an ces to th e i ma ge, th e ton al r an ge was n ot as

ex ten si ve as th e pl ai n sal ted or gel ati n si z ed paper s. S tar ch i s

typi cal l y a du l l su bstr ate an d as a r esu l t r efr acts l i ttl e l i gh t .

In spi te of th at i t h ol d s de ta i l i n both th e sh ado w an d

h i gh l i gh t r egi on s ex cepti on al l y wel l .

S u bstan ti al r esear ch wa s n ece s sar y wh en sel ec ti n g su i tabl e

paper s for th e sal t pr i n t tests o wi n g to th e en or mou s r an ge of

paper types av ai l abl e.

E x pl or i n g th e paper su r face u si ng th e Nova Nan oS E M pr ovi ded

an i n si gh t to h ow si z ed pa per i n fl u en c es th e pr i n t . Th e paper

ch oi ce di d i n fl u en ce th e col ou r , con tr ast an d t on al separ ati on

of th e i mage. S mooth h ar der fi n i sh ed , su r face si z ed paper s

gave a sh ar per mor e br i l l i an t i mage wi th c ool er col ou r ton es .

S i l ver n i tr ate sol u ti on s r espon d u n favou r abl y to an y ch emi cal

paper addi ti ves th er efor e on l y qu al i ty 1 00 % cotton , water

col ou r paper s can be u sed. A K D , th e syn th eti c ar ch i val

8 4

i n ter n al si z i n g agen t , sti l l cr eated ch emi cal foggi n g wi th th e

ex cepti on of al bu men pr i n ts . A n u n der stan di n g of th e

str u ctu r e an d comp osi ti on of pa per s was an e ssen ti al t ool i n

con tr ol l i n g th e col ou r an d th e fi nal l ook of th e pr i n t .

A gl ass r od an d a syr i n ge pr ovi de d gr eater accu r acy over th e

amou n t of sol u ti on th at wa s ap pl i ed. Th e c oati n g wa s m or e

even an d th e r ati o bet ween th e sal t an d th e si l ver n i tr ate

sol u ti on was mor e c on tr ol l ed. B y i n cr easi n g th e vol u me of th e

al bu men an d a r r owr o ot sol u ti on s, coati n g pr obl e ms wer e

r esol ved. A ppl yi n g th e sec on d coati n g of al bu men was

con si sten tl y su c ces sfu l on ce th e ch l or i de i n i sopr o pyl al c oh ol

wa s omi t ted.

M an y th eor i es state th e c ol ou r of a ph ot ogr aph de pen ds on th e

si l ver par ti cl e si z e an d sh ape . T h e col ou r of metal col l oi d s i s

a r esu l t of th e abs or pti on an d s c atter i n g of l i gh t . R M IT Ph ysi cs

depar tmen t‟ s FE I No va Nan oS E M wi th an E D A X X -r ay de tect or

wa s u sed to s ear ch for a r el ati on sh i p bet ween th e var yi n g

si z e s an d sh apes o f si l ver par ti cl es an d h ow th e y ar e

di sper sed wi th i n th e pr i n t to affect col ou r .

Th e si z e var i ati on s of th e si l ver par ti cl es wi th i n a si n gl e pr i n t

sampl e wer e u n ex pec ted . Wr i tte n mater i al sta tes th e si z e of

si l ver par ti cl es r a n ges fr om 10n m to 1 3 0 n m (War e, 1 9 94 ) . A l bu men par ti cl es ar e sai d to be l ess th an 3 n m to 50 n m, wi th most bet ween 5 n m an d 2 0 n m (Rei l l y an d K en n edy, 19 84 ) . It wou l d be ex pe cted f or a speci fi c col ou r , th e par ti cl es wou l d be

wi th i n a si z e r an ge. For ex ampl e , at th e smal l er en d of th e

scal e , yel l o w si l ver par ti cl es wo u l d r an ge fr om 1 0 n m to 2 0 n m

an d at th e l ar ge r en d of th e scales par ti cl es of a gr ey/ gr een

col ou r wou l d r an ge fr om 1 2 0 n m to 1 3 0 n m (War e, 1 9 94 ) . Th i s

di d n ot appe ar to be so. S i l ver par ti cl es r an ged fr om 1 . 4 5 µ m

to 8 2 0 n m. In som e cas es i t w ou l d be ex pe cted th e si l ver

par ti cl es may cl u mp tog eth er maki n g th e par ti cl es appear as

on e . Th e amou n t of sa mpl e s m i gh t h ave l ed to a l evel of

con fi den ce i n cer tai n fi n di n gs bu t th e evi den ce r e th e si z e

came fr o m th e ex ami n ati on of a l ar ge n u mber of sa mpl es of

si l ver par ti cl es sh o wi n g th e sa mpl es ex ceede d th at o f th e

8 5

pr evi ou sl y r epor te d ph o tol yti c s i l ver par ti cl es . E x ampl es of

th ese par ti cl e si z e s ar e sh o w i n Fi gu r e 5 -4 ti tl ed B r on z i n g

Hi gh M agn i fi cati on .

A l th ou gh th e par ti cl es ‟ si z e an d sh ape may h ave so me ef fect

on col ou r , fi n di n gs of th i s r e sear ch su ggest th e bi n der s,

paper s, si z i n g, ex posu r e, h u midi ty , th e pr ocessi n g an d i n

par ti cu l ar ton i n g , h ave a mu ch greater effect.

In vesti gati n g th e t on e r epr odu cti on of th e sal t pr i n t wa s ti me

con su mi n g. E ach n egati ve type wa s fou n d to h ave n u mer ou s

var i ati on s an d pr obl e ms. Th e t i me sp en t on th e n egati ve,

especi al l y th e di gi tal as pect, be came di s pr opor ti on ate t o th e

en ti r ety of th i s r esear ch paper . A l th ou gh a gr eat deal mor e

ex pl or ati on cou l d be car r i ed ou t, th e r esu l ts at th i s poi n t wer e

fel t to be r eason abl y con cl u si ve.

Th e fi l m n egati ve offer s th e gr eatest ton al r an ge, pr ovi di n g

su btl eti es o f ton e s th at th e di gi ta l n egati ve cou l d n ot pr odu ce.

E x ten si ve testi n g pr ov ed th at Il for d FP4 n egati ves pr oces sed

i n th e dou bl e str en gth PM K devel oper pr ovi de d th e gr eat est

con ti n u ou s ton e an d pr odu ced t h e ex tr a den si ty de si r abl e for

sal t pr i n t i n g. Th i s i s wh en th e sa l t pr i n ts ‟ sel f -ma ski n g abi l i ty

wa s u ti l i sed to max i mi se th e ton a l r an ge.

D ots mak i n g u p an i n kjet n egat i ve ar e at on e l evel bu t the

si l ver an al ogu e n egati ve pr ovi de s a gr adati on of t on es at man y

l evel s. A ddi ti on al l y, a r el i ef of di ffer en t l evel s i n th e fi l m

emu l si on o ffer s fu r th er di men si o n s. PM K devel oper f or med th e

gr eatest r el i ef i n th e fi l m emu l si on . Th e i n kjet n egati ves wi th

si mi l ar col ou r s to th e FP4 / PMK n egati ve pr oved to su r pass a

n u mber of ty pes of an al ogu e fi l m n egati ves tes ted i n ter m s of

ton al r an ge .

Th e col ou r an d c on tr ast of th e pr i n t ar e i n fl u en ced by th e

i n ten si ty an d col ou r of th e ex posi n g l i gh t. A UV l i gh t b ox

offer s s tabi l i ty an d r epeatabi l i ty wh i l e su n l i gh t ‟ s UV an d

vi si bl e spectr u m ar e var i abl e an d compl ex . Th e i mage s

ex posed i n th e su n l i gh t ten d to r etai n war mer ton es an d

8 6

gr eater den si ty. Th i s war mth ap pear s to devel op th r ou gh th e

di ffer i n g vi si bl e an d UV r ays an d al so h u mi di ty con ver ti n g

mor e si l ver ch l or i de to me tal l i c si l ver wh i ch gr avi tat e to th e

pr i n t su r face.

Tests wi th cu t -off fi l ter s pr oved con cl u si vel y t h e sen si ti vi ty

of th e si l ver ch l or i de t o th e vi si b l e spectr u m i s far mor e wi de -

r an gi n g th an pr evi o u sl y r epor ted i n var i ou s wr i tten mater i al .

A cti n i c B L 4 0 watt mer cu r y vapou r fl u or escen ce l am ps

mi r r or ed th e spectr al qu al i ty of th e sol ar spectr u m. Th i s

ex pl ai n s th e poor ou tcome fr om fi l m wi th a h i gh base fog or

u n bu i l t UV fi l ter s su ch as K odak D u r ocl ear ™ as i n su ffi ci en t

l i gh t wa s tr an smi t ted at th e si l v er ch l or i de ‟ s peak sen si ti vi t y.

Ho w th e l on ger wave l en gth s i n th e spectr u m pl ay a p ar t i n

ex ten di n g th e ton al r an ge an d col ou r s cal l s for p ossi bl e

fu r th er r esear ch .

D espi te adh er i n g to ar ch i val pr acti ces i n pr o cessi n g an d i n

par ti cu l ar th e wash i n g, su l ph u r wa s sti l l fou n d t o be r esi di n g

i n th e paper . Th e var i ou s me t h ods of t esti n g for r esi du al

sodi u m th i osu l ph at e (r esu l ti n g i n su l ph u r ) appear to be l ess

th an adequ ate. Th e E D A X X -r ay detector r eveal ed th at bi n der s

ex pected to pr ote ct th e si l ver par ti cl es fr om su l ph u r

attach men t appear i n eff ecti ve. S u l ph u r was di s cover ed on th e

si l ver par ti cl e s o f gel ati n bi n de r s . Ho wever on al bu men an d

star ch bi n der s th e atomi c per cen tage was gr eater . S u l ph u r h as

a damagi n g effect on i mage stabi l i ty. Fu r th er r esear ch on each

of th e pr oce ssi n g ste ps may co n tr i bu te to establ i sh m en t of

meth od s t o ex ten d pr i n t i mag e stabi l i ty of th e sal t an d

al bu men pr i n t.

E ach step of pr oces si n g i n fl u en ces th e pr i n t col ou r an d i ts

l i fe. A pr ocedu r e for th e i n i ti al wa sh i n g stag e wa s d evel ope d

to el i mi n ate th e stai n i n g th a t was appar en t th r ou gh ou t

pr ocessi n g.

Th e most dr amati c ch an ge i n t h e col ou r of sal t pr i n t came

th r ou gh th e var i ou s ton i n g for mu l as. M an y of th e ton i n g

for mu l as pr oved to be t oo con c en tr ated for th e al bu men an d

8 7

gel ati n pr i n ts. Th i s was easi l y r esol ved by di l u ti on of th e

ton er wh i ch appear ed to h ave mi n i mal effect on th e l on g t er m

stabi l i ty.

Th e ear l y pr oces ses ar e oft en tau gh t an d con si der ed pu r el y an

ar t for m wh er e a mi sta ke or acc i den t i s con si der ed cr eati ve.

Th e h i stor y an d th e ch emi cal acti vi ty, r espon se s an d l on gevi ty

ar e n ei th er di scu ssed n or even con si der ed r el evan t. A l l too

often , tex t on th e sal t pr i n t i s w r i tten i n a wa y wh i ch al mo st

bel i ttl es th e pr oce sse s. It cl ose s a d oor on th e p eopl e wh o

wi sh to ex pl or e, u n der stan d an d con tr ol th e pr oces s. A l th ou gh

often i t i s cl ear fr om wh er e th e wr i tten mater i al or i gi n ate s, i t

i s di sapp oi n ti n g so man y au th o r s h ave n ot r efer en ce d th ei r

or i gi n al sou r ce.

8 8

C h a p t e r 8 C O N C L U S I O N

S al t pr i n ti n g i s an in ex act sci en ce.

D espi te r i gor ou s car e an d atten ti on to coati n g, ex posu r e an d

pr ocessi n g, th e n u mber of var i a bl es at ever y ph ysi cal stag e

ten ds to ma ke ex act r epeatabi l i ty i mpr obabl e . It i s di ffi cu l t to

pr ovi de a cl ear -cu t r ati on al e for th e col ou r an d appear an ce of

th e sal t pr i n t i n ter ms of th e se var i abl es u n l ess th ey ar e

man aged an d addr es sed du r i n g each stage of pr odu cti on .

Th er e ar e a n u mb er of mech an i s ms t o c on tr ol th e col ou r an d

th e appear an ce of th e sal t pr i n t. Ch l or i de for mu l as an d

addi ti v es al l o w s ome con tr ol of col ou r an d con tr ast bu t i t i s

th e bi n der s th at ch an ge h o w th e si l ver i mage si ts on th e pa per

su r face wh i ch of fer gr eater con tr ol . Th i s i s attr i bu tabl e to

l i gh t r efr acti n g th r ou gh th ese b i n der s as th ey l i ft th e i mage

u p or ou t of th e paper fi br es.

Th e p aper s u sed for sal t pr i n t i n g h ave a con si der abl e effect

on th e col ou r an d ton al r an ge . T h e paper mi l l s pr odu ce si z ed

paper s wi th h ar d or soft su r face s . Th ese su r faces dr ama ti cal l y

affect th e ton al r an ge an d th e pr i n t col ou r , var yi n g fr om co l d

bl u e / br own c ol ou r s to war m r i ch pu r pl e/ r ed/ br own .

Un der stan di n g th e con str u cti on an d comp osi ti on of th e pa per

pr ovi des th e abi l i ty t o pr edi ct an d con tr ol col ou r . S peci fi c

paper s can be sel e cted t o pr ovi de defi n ed ton al r an ges an d

acu tan ce.

Th e ex ten si ve r esear ch i n to fi n d i n g th e best type o f n egati ve

wa s val u abl e. Th e Il for d FP4 n egati ve wi th th e gr een / br own

tan n i n g stai n fr om th e PM K devel oper pr ovi ded a su b stan ti al

ton al r an ge by u ti li si n g th e in tr i n si c sel f -mas ki n g abi l i ty .

In kjet n egati ve s wh e n du pl i ca ti n g th e PM K stai n col ou r

pr ovi ded a r eason abl e ton al ran ge al th ou gh th ey di d n ot

separ ate ton e s or per for m wel l i n th e h i gh l i gh ts an d sh ado w

r egi on s. Th ey di d h o wever per for m better i n con tr ast an d

8 9

ton al r an ge th an man y an al ogu e fi l ms an d n egati v e en l ar gi n g

pr ocess es.

Ch oosi n g t o u se a con tr ol l ed UV l i gh t box r ath er th an su n l i gh t

to ex pose pr ovi d e d pr edi ctabi l i ty bu t l ost mu ch of th e

spectr u m to wh i ch si l ver ch l or i de i s al so sen si ti ve. Th e vi si bl e

spectr u m an d th e h u mi di t y c o n tr i bu te to ex tr a war mth i n

col ou r an d den si ty of th e fi n al p r i n t. E x posi n g th e pr i n t cl ose

to br on z i n g i n di cates a h i gh p or ti on of si l ver ch l or i de h as

been con ver ted to metal l i c si l ve r . Th i s makes th e pr i n t l ess

vu l n er abl e to ox i dati on , assi st i n g i n th e pr i n ts‟ l on gevi ty.

Ton i n g offer s th e gr eatest con t r ol an d dr amati c ch an ge of

col ou r wh i l e al s o pr ote cti n g th e l i fe of th e pr i n t . P r i n ted

mater i al on ton i n g an d th e o th er pr ocessi n g meth od s h o wever

wa s fr au gh t wi th con tr adi ctor y i n for mati on . Th e devel op men t

of a pr e- wash m et h od r esol v ed m a n y of th e stai n i n g pr obl ems .

D espi te al l effor ts to u se th e most ar ch i val meth ods of

pr ocessi n g , th e E D A X X -r ay detector i n di cated su l ph u r wa s

sti l l pr esen t i n th e paper . E ven t h ou gh t est s for r esi du al fi x er

i n di cated th e paper was fr ee f r om th i s damagi n g su l ph u r

el emen t.

Th e th eor y of th e par ti cl e si z e a n d sh ape di ctati n g th e col ou r

of th e sal t pr i n t fel l sh or t wh e n compar i n g th e col ou r s th at

ar e con tr ol l ed by th e bi n der s, ton er s an d paper s. Th e Nan oS EM

pr ovi ded i mage s i n di cati n g th e si z e of th e si l ver par ti cl es i n

most sam pl e s wer e too di ver se i n si z e to di cta te on e l i mi t ed

col ou r r an ge. A l th ou gh su l ph u r on th e si l ver par ti cl e s may

h ave so me bear i n g on c ol ou r , t h e paper bi n der s, ton er s an d

ex posu r e h ave a far gr eater effect an d con tr ol on th e fi n al

col ou r of th e sal ted pap er pr i n t.

Th e sal t pr i n t col ou r an d ton es th er efor e can be con tr ol l ed

an d pr edi cte d. Th i s h o wever i s l i mi ted by th e abi l i ty of th e

sal t pr i n ter to r epeat each of th e oper ati on s con si sten tl y .

9 0

A P P E N D IX 1 S A L T F O R M U L A S

S O D I U M C H L O R I D E F O R M U L A

D i sti l l ed Water 2 5 0 ml

S odi u m ch l or i de 5 gm

Meth od :

A dd th e sal t to th e r oom te mper a tu r e di sti l l ed wa ter . Th i s wi l l

di ssol ve ea si l y an d i s r eady for u se wh en di ss ol ved.

A M M O N I U M C H L O R I D E F O R M U L A

D i sti l l ed Water 2 5 0 ml

A mmon i u m ch l or i de 5 gm

Meth od :

A dd th e sal t to th e r oom te mper a tu r e di sti l l ed wa ter . Th i s wi l l

di ssol ve ea si l y an d i s r eady for u se wh en di ss ol ved.

S O D I U M C H L O R I D E S O L U T I O N + G E L A T I N

5 0 ml D i sti l l ed Water

2 gm Gel ati n

2 0 0 ml D i sti l l ed Water at 3 8 ° C

5 gm S odi u m ch l or i de

Meth od :

1 . M i x 2 gm of gel ati n wi th 5 0 ml of di sti l l ed water at r oom

temper atu r e an d l eave for 1 0 mi n u tes.

2 . Heat th e 2 0 0 ml of di sti l l ed wa ter to 3 8 ° C.

3 . A dd th e sal t wh en di ssol v ed .

4 . S ti r i n th e gel ati n.

5 . Th e sol u ti on i s r eady wh en co ol e d to a bou t 2 0 ° C.

9 1

A M M O N I U M C H L O R I D E S O L U T I O N + G E L A T I N

5 0 ml D i sti l l ed Water

2 gm Gel ati n

2 0 0 ml D i sti l l ed Water at 3 8 ° C

5 gm A mmon i u m Ch l or i de

Meth od :

1 . M i x 2 gm of gel ati n wi th 5 0 ml of di sti l l ed water at r oom

temper atu r e .

2 . L eave for 1 0 mi n u tes.

3 . Heat th e 2 0 0 ml of di sti l l ed wa ter to 3 8 ° C.

4 . A dd th e sal t wh en di ssol v ed .

5 . S ti r i n th e gel ati n.

6 . Th e sol u ti on i s r eady wh en co ol e d to abou t 2 0 ° C.

S O D I U M C H L O R I D E + S O D I U M C I T R A T E

2 5 0 ml D i sti l l ed Water

5 gm S odiu m chl ori de

5 gm S odi u m ci tr ate

Meth od :

1 . A dd th e sal t to th e di sti l l ed wa te r . It wi l l di ssol v e easi l y.

2 . A dd 5 gm sodi u m ci tr ate; i t i s r eady for u se wh en th i s h as

di ssol ve d.

A M M O N I U M C H L O R I D E + S O D I U M C I T R A T E

2 5 0 ml D i sti l l ed Water

5 gm A mmon iu m Ch l ori de

5 gm S odi u m ci tr ate

Meth od :

1 . A dd th e sal t to th e di sti l l ed wa te r . It wi l l di ssol v e easi l y.

2 . A dd 5 gm sodi u m ci tr ate; i t i s r eady for u se wh en th i s h as

di ssol ve d.

9 2

S O D I U M C H L O R I D E + P O T A S S I U M D I C H R O M A T E

D i sti l l ed Water 2 5 0 ml

S odiu m chl ori de 5 gm

Meth od : 1 . A dd th e sal t to th e di s ti l l ed wa te r . It wi l l di ssol v e easi l y.

2 . Take 3 0 ml of sal t sol u ti on .

3 . A dd 2 dr ops of th e 5 % potassi u m di ch r omate sol u ti on .

A M M O N I U M C H L O R I D E + P O T A S S I U M D I C H R O M A T E

D i sti l l ed Water 2 5 0 ml

A mmon i u m Ch l or i de 5 gm

Meth od : 1 . A dd th e sal t to th e di sti l l ed wa te r . I t wi l l di ssol v e easi l y.

2 . Take 3 0 ml of sal t sol u ti on .

3 . A dd 2 dr ops of th e 5 % potassi u m di ch r omate sol u ti on .

P O T A S S I U M D I C H R O M A T E 5 % S O L U T I O N

D i sti l l ed Water at 2 0 ° C 1 0 0 ml

Potassi u m di ch r omate 5 gm

Meth od : 1 . Heat water to 2 0 ° C .

2 . Pu t on gl oves, eye pr ote cti on an d mask.

3 . D i ssol ve po tassi u m di ch r omate i n th e di sti l l ed water .

4 . S tor e i n a smal l stopper ed br o wn bottl e .

A L B U M E N F O R M U L A – A M M O N I U M C H L O R I D E

A l bu men (egg wh i t e) 250 ml (8 - 10 eggs)

Gl aci al aceti c aci d 0 . 5 ml

D i st i l l ed water 8 ml

A mmon i u m ch l or i de 4 gm

Meth od :

1 . Car efu l l y separ ate e gg wh i te s r emovi n g al l con tami n ati on of yol k, str i n gy ti ssu e, bl o od or sh e l l fr om th e egg wh i te s.

3 . A dd al l ch emi cal s .

4 . B eat th i s sol u ti on u n ti l i t i s con ver ted to fr oth .

5 . L e t th e sol u ti on si t for 2 4 h ou rs i n th e r efr i ger ator .

9 3

6 . B r in g to r oom temper atu r e .

7 . S tr ain th ou gh mu sl i n or ch eesecl oth .

8 . Cover an d r efr i ger ate for 1 we ek to fer men t.

A R R O W R O O T F O R M U L A ( W A L L A N D J O R D A N , 1 9 7 5 )

D i sti l l ed water 7 5 0 ml

A r r owr oot star ch 2 0 gm

D i sti l l ed water 2 5 0 ml

A mmon i u m ch l or i de 1 4 gm

S odi u m car bon ate 2 3 gm

Ci tr i c aci d 7 gm

Meth od : 1 . M i x th e arr owr oot star ch wi th abou t 2 0 ml of th e 7 50 ml

vol u me of th e di sti l l ed water mak i n g a smooth cr eam y

su spen si on .

2 . B r i n g to th e b oi l th e bal an ce of di sti l l ed water .

3 . Gr adu al l y add th e star ch wh i l e st i r r i n g.

4 . Con ti n u e to boi l u n ti l th e l i qu i d is tr an sl u cen t.

5 . In th e secon d am ou n t of di sti l l ed wat er di ssol ve th e

ammon i u m ch l or i de, s odi u m car b on ate an d ci tr i c aci d . Wh i l e

addi n g th e ci tr i c aci d th i s sol u ti o n wi l l effer vesc e.

6 . A dd th e sol u ti on to th e ar r owr o ot an d boi l for 5 mor e

mi n u tes. Th e smel l of a mm on i a wi l l be qu i te str on g .

7 . S tr ai n th r ou gh mu sl i n or ch eese cl oth wh i l e h ot an d al l o w t o

cool .

8 . R emove an y s ki n th at h as for med befor e appl yi n g to th e

paper .

S I L V E R N I T R A T E S E N S I T I Z I N G F O R M U L A

D i sti l l ed or de -mi n er al i z ed water 5 0 ml

6 gm S i l ver n i tr ate

Meth od :

1 . Wi th gl oves an d eye pr ot ecti on i n pl ace, a dd th e si l ver n i tr ate

to th e di sti l l ed wat er at r oom te mper atu r e.

9 4

A P P E N D I X 2 T O N E R F O R M U L A S

2 . S tor e i n a br own gl ass bottl e.

G O L D B O R A X T O N E R ( F A R B E R , 1 9 9 8 )

D i sti l l ed water 1 0 00 ml

S odi u m tetr abor ate (bor ax ) 6 gm

Gol d ch l or i de 1 % sol u ti on 1 2 ml

Meth od :

1 . Heat di sti l l ed wat er to 3 8 ° C.

2 . A dd th e s odi u m t etr abor ate .

3 . A dd th e gol d ch l or i de.

S O D I U M A C E T A T E G O L D T O N E R ( J A M E S , 2 0 0 2 )

D i sti l l ed water 1 0 00 ml

S odi u m acetate 1 0 gm

Gol d ch l or i de 1 % sol u ti on 1 0 ml

Meth od : 1 . Heat di sti l l ed wat er to 3 0 ° C.

2 . A dd th e sodi u m ace tate .

3 . A dd th e gol d c h l or i de.

T H I O C Y A N A T E G O L D T O N E R 1 ( R E I L L Y , 1 9 8 0 )

D i sti l l ed water 5 0 0 ml

S odi u m th i ocyan ate 9 gm

Gol d ch l or i de 1 % sol u ti on 3 5 ml

Meth od : 1 . Heat di sti l l ed wat er to 3 0 ° C.

2 . A dd th e sodi u m t h i oc yan ate .

3 . A dd t h e gol d ch l or i de.

9 5

9 6

T H I O C Y A N A T E G O L D T O N E R 2 ( C R A W F O R D , 1 9 7 9 )

5 0 0 ml D i sti l l ed water

2 . 5 gm S odi u m th i ocyan ate

1 gm Tar t ar i c aci d

2 . 5 gm S odi u m c h l or i de

1 0 ml Gol d ch l or i de 1 % sol u ti on

D i sti l l ed water to mak e 5 0 0 ml

Meth od : 1 . Heat di sti l l ed wat er to 3 0 ° C.

2 . A dd th e s odi u m t h i oc yan ate .

3 . A dd tar tar i c aci d.

4 . A dd sodi u m ch l or i de.

5 . A dd th e gol d ch l or i de.

6 . A dd wa ter to make 5 0 0 ml .

P L A T I N U M T O N E R ( J A M E S , 2 0 0 2 ) A D J U S T E D

D i sti l l ed water at 3 0 ° C 10 00 ml

Potassi u m ch l or opl ati n i te 2 0 % 2 . 0 ml

Ci tr i c aci d 2 . 5 gm

Meth od : 1 . Heat di sti l l ed wat er to 3 0 ° C.

2 . A dd th e Potassi u m ch l or opl ati n i t e .

3 . A dd th e ci tr i c aci d.

4 . Th e ton er i s r eady for u se wh en cool ed to 2 0 ° C.

P A L L A D I U M T O N E R ( J A M E S , 2 0 0 2 ) A D J U S T E D

D i sti l l ed water 1 0 00 ml

S odi u m ch l or opal l adi te 1 5 % sol u ti on 2 .0 ml

Ci tr i c aci d 2 .5 gm

S odi u m ch l or i de 2 .5 gm

Meth od : 1 . Heat di sti l l ed wat er to 3 0 ° C.

2 . A dd th e S odi u m ch l or opal l adi te.

3 . A dd th e ci tr i c aci d, di ssol ve.

4 . A dd th e S odi u m ch l or i de .

5 . Use wh en co ol ed to 2 0 ° C.

9 7

A P P E N D I X 3 D E V E L O P E R A N D F I X E R F O R M U L A S

P M K D E V E L O P E R ( H U T C H I N G S , 1 9 9 2 )

S o l uti o n A

D i sti l l ed water at r oom te mper at u r e 7 5 0 ml

M etol 1 0 gm

S odi u m bi su l fi te 2 0 gm

Pyr ogal l ol 1 0 0 gm

Water to make 1 0 00 ml

S o l uti o n B

D i sti l l ed water at r oom te m per at u r e 1 4 00

S odi u m metab or ate 6 0 0 gm

Water to make 2 0 00 ml

Meth od : S to c k S ol uti o n A

1 . Wei gh ou t th e sodi u m bi su l fi te.

2 . A dd a pi n ch of th e sodi u m bi su l fi te to th e 7 5 0 ml of water

an d set th e r emai n der asi de.

3 . A dd th e metol an d sti r u n ti l com pl etel y di s sol ve d.

4 . A dd r emai n i n g sodi u m bi su l fi te, sti r u n ti l di ssol ved.

If a ven ti l ati n g h ood i s n ot avai l a bl e , measu r e th e 5 .

pyr ogal l ol ou tsi de.

6 . Pu t on gl oves, mas k an d eye pr ot ecti on .

7 . M easu r e ou t th e pyr ogal l ol an d add to th e sol u ti on .

S to c k S ol uti o n B 1 . D i ssol ve th e so di u m me tabor ate i n th e 1 40 0 ml of water .

2 . A dd wa ter to make 2 0 0 0 ml .

3 . S tor e i n br own gl ass bot tl es cl ear l y mar ked.

9 8

F I X E R

Water 7 5 0 ml

S odi u m th i osu l fate 1 5 0 gm

S odi u m car bon ate 2 . 5 gm

Water to make 1 0 00 ml

Meth od :

1 . Heat th e 7 5 0 ml of water to 3 0 ° C .

2 . A dd th e s odi u m th i osu l fat e.

3 . A dd th e sodi u m car bon ate.

4 . A dd wa ter to make 1 0 0 0 ml .

K O D A K F I X E R T E S T S O L U T I O N F T 1

Water 1 0 0 ml

Potassi u m i odi de 1 9 gm

Meth od : 1 . Heat water to 3 8 ° C .

2 . A dd potas si u m i odi de.

3 . It i s r eady for u se wh en di ss ol ve d an d cool ed t o 2 0 ° C.

K O D A K F I X E R T E S T S O L U T I O N S T - 1

Water at 3 8 ° C 1 2 5 ml

S odi u m su l ph i de 2 gm

Meth od : 1 . Heat water to 3 8 ° C

2 . A dd S odi u m su l ph i de.

3 . R eady for u se wh en di ss ol ved an d cool ed t o 2 0 ° C.

C L E A R I N G A G E N T

Water at 3 0 ° C 1 0 00 ml

S odi u m su l ph i te 1 0 gm

Meth od : 1 . Heat water to 3 0 ° C.

2 . A dd S odi u m su l ph i te.

3 . Wh en di ssol ved an d th e t emper at u r e i s appr ox i matel y 2 0 ° C

i t i s r eady for u se.

9 9

K O D A K H Y P O T E S T S O L U T I O N H T 1 A ( R E S I D U A L F I X E R )

D i sti l l ed water at 2 0 ° C 1 8 0 ml

Potassi u m per man gan ate 0 . 3 gm

S odi u m h ydr ox i de 0 . 6 gm

D i sti l l ed water to mak e 2 5 0 ml

Meth od : 1 . Heat 1 8 0 ml water to 2 0 ° C.

2 . A dd potas si u m per man gan ate, wh en di ssol ved .

3 . A dd th e S odi u m h ydr ox i de .

4 . A dd wa ter to make 2 5 0 ml .

T o Use: 1 . D i l u te 1 ml of th e sol u ti on i n 12 5ml s of water .

i n to a gl ass 2 . Pou r 1 5 ml of th e pr epar ed sol u ti on

con tai n er .

3 . Take th e pr i n t fr om th e wash tr ay .

4 . A l l ow to dr i p for 3 0 secon ds i n to th e sol u ti on .

5 . If an y r esi du al fi x er r emai n s i n th e paper i t wi l l ch an ge

th e sol u ti on fr om pu r pl e to or an ge i n 3 0 secon ds. It

become s col ou r l es s agai n i n on e mi n u te.

1 0 0

G L O S S A R Y

Ac ti ni c l i g ht: L i gh t i n th e UV , vi ol et an d bl u e r egi on of the

spectr u m th at i s r equ i r ed for l i gh t -i n du ced ch emi cal r eacti on s

i n pr i n ti n g -ou t pr ocesse s to cr eat e an i mage.

Al k al i ne : Opposi t e of aci d wi th a pH gr eater th an 7 on a pH

scal e.

Anhydr o us : Fr ee fr om water .

Ar r o wr o o t: S tar ch made fr om tu ber ou s r oots, i n cl u di n g

potatoe s. It i s a fi n e wh i te p o wd er th at i s u sed for si z i n g an d

bi n di n g.

Bi nde r : Th e su bstan c e th at bi n ds togeth er t wo or mor e

mater i al s or ch emi cal s i n a mi x tu r e , i . e. gel ati n an d al bu men

bi n der s h ol d th e ch l or i de, di sper si n g th e si l ver ch l or i de wh i l e

adh er i n g i t to th e paper .

Br o nz i ng : Th i s des cr i bes th e sa tu r ati on poi n t of a sal t pr i n t

ex posu r e . Th e metal l i c si l ver p ar ti cl es si t so cl o se togeth er

th ey for m a l aye r on th e su r face.

Buc k l e Br ush : A test tu be, gl as s or pl asti c tu be wi th cott on

wool t wi s ted ti gh tl y i n on e en d.

Came r a L uc i da: N ot actu al l y a c amer a bu t a n o pti cal dr awi n g

ai d.

D.ma x i s th e max i mu m d en si ty r e cor ded on fi l m or paper .

D.mi n i s th e mi n i mu m d en si ty r e cor ded on fi l m or paper .

De c a-hydr ate d : C on tai n s 1 0 mol ecu l es of water .

De -i o ni z e d Wate r : Water pu r i fi ed fr om al l i n or gan i c sal ts by

an i on ex ch an ge pr ocess or rever se osm osi s bu t or gan i c

comp ou n ds ma y sti l l r emai n .

De l i que sc e nt : A bsor bs water f r o m th e ai r .

1 0 1

De -mi ne r al i z e d Wate r : S ame as d ei on i sed water .

De nsi ty : A m easu r e of l i gh t ab so r bed or tr an smi tted i n an ar ea

of an i mage. Th i s can be measu r ed by a den si tome ter . D en si ty

i s a l ogar i th mi c val u e. If on e ar ea of a n egati ve tr an smi t s

twi ce as mu ch l i gh t as an oth er th e den si ty di ffer en ce i s 0 . 3

(i . e. th e l og of 2 ) Usi n g S tep wedges th at ar e 2 1 steps wi th a

den si ty u n i ts of . 1 5 step i n ter val s gi ves a total r an ge of 3 . 1 5

den si ty u n i ts. Cou n ti n g th e n u mber of steps th at ar e di sti n ct

i n th e pr i n t an d mu l ti pl yi n g th i s by th e . 1 5 den si ty i n ter val

bet ween th e step s , wi l l gi ve th e ex posu r e r an ge i n l og u n i ts.

To con ver t th i s r an ge to sto ps m u l ti pl e th e l og u n i ts by 3 . 3 .

De nsi ty R ang e : Th e di ffer en ce b et ween th e l i gh test r ecor ded

ar ea an d th e dar kes t r ecor ded ar ea. In fi l m i t r efer s to

measu r i n g th e th i n n est par t of th e n egati ve, th en measu r i n g

th e den ses t par t of th e n egati v e an d su btr acti n g th i s val u e.

Th i s wi l l gi ve y ou th e d en si ty r a n ge. D en si tome ter s ar e u se d

to accu r atel y mea su r e den si ty.

Di sti l l e d wate r : A l l i m pu r i ti es a r e r emoved by boi l i n g wa ter

an d con den si n g th e stea m.

Effl o r e sc e nt : L ose moi stu r e.

E xo the r mi c : Cr eate h eat wh en di s sol vi n g .

Fadi ng : D eter i or ati on of th e sal t pr i n t th r ou gh poor fi x i n g,

i n compl ete wa sh i n g ou t o f fi x er s an d ai r bor n e c on tami n ati on

attr i bu te to fadi n g.

Fi xe r : A mmon i u m th i o su l fate a n d sodi u m th i o su l ph ate ar e

u sed to r em ove th e u n ex pose d an d th er efor e sti l l l i gh t

sen si ti ve si l ver sal ts.

Fo g : Non -i mage si l ver th at sh ows as di scol ou r ati on , u su al l y

cr eated by con tami n at i on or ex posu r e on th e l i gh t sen si ti ve

su r face befor e pl aced u n der a n egati ve for pr i n ti n g.

1 0 2

Ge l ati n: A pr otei n bi n der cr eated fr om an i mal h i des, bon es

an d ti ssu e s. It i s an i m por tan t bi n der i n ph o togr aph y an d

si z i n g i n paper maki n g. V ar i ou s gr ades ar e ava i l abl e.

L*a .b . CIE 1 9 7 6 L*a . b . i s based di r ectl y on th e C IE 1 9 3 1 X YZ

col ou r space. It i s a l i n ear per cepti bi l i ty of col o u r di ffer en ces.

Th e n on l i n ear r el ati on s for L * a . an d b . ar e i n ten ded t o mi mi c

th e n on l i n ear r espon se of th e eye. L * for l i gh tn ess, a .

r epr esen ts h o w r ed or gr een th e col ou r i s an d b . r epr esen ts

h ow bl u e or yel l o w i t i s. E ver y col ou r h as an L * a . b. val u e.

S pectr oph oto meter s gi v e L *a. b. n u mber s for a par ti cu l ar

col ou r .

Late n t I mag e : A n i n vi si bl e i mage for med on sen si ti se d fi l m or

paper by ex po su r e to l i gh t. Th e ex posu r e cr eates smal l

cl u ster s of si l ver at om s i n si l ver h al i de cr ystal s th at ar e i mage

for mi n g wi th ch e mi cal devel o pme n t.

Lati t ude : Th e ac ceptabl e r an ge of an i mage befor e over -

ex posu r e an d u n der -ex posu r e cau se l oss o f detai l .

Li nte r s: Fi br es u se d to mak e cotton paper . Th ese ar e th e

sh or ter fi br es l eft af ter th e c otton h as gon e th r ou gh th e

gi n n i n g mach i n e. Th e l on ger fi bres ar e made i n to th r ead.

M e asl e s: B l otch y l i gh t mar ks c au sed by i n su ffi ci en t si l ver ;

al so a ter m u sed t o de scr i be da r k mar ks made fr o m po or or

ex h au sted fi x i n g bath .

M o no -hydr ate d : C on tai n s on e m o l ecu l e of water .

M S DS : M ater i al s S afety D ata S h eet s. Th e se pr ovi de a fu l l

descr i pti on of th e ch e mi cal s, safe h an dl i n g, pr otecti on

r equ i r ed an d fi r st -ai d tr eatmen t.

Oxi dati o n: Th e r e moval of an e l ectr on or el ec tr on s fr o m an

atom or a mol e cu l e .

P ho to c he mi c al Ac tio n : A ch an ge can on l y b e ma de by l i gh t

th at i s abs or bed. Th e a mou n t of ph ot och emi cal ch an ge i s

1 0 3

pr opor ti on ate t o th e l i gh t i n te n si ty mu l ti pl i ed by ti me of

i l l u mi n a ti on .

P ho to l ysi s: In th e sal t pr i n t i t is th e acti vi ty cr eate d by th e

ex posu r e to l i gh t th at ch an ges th e si l ver ch l or i de to metal l i c

si l ver .

P ur i fi e d Wate r : Th i s gen er al l y mean s water pu r i fi ed for

h u man con su mpti on wh i ch sti l l may con tai n sal ts an d or gan i c

matter .

P yr o g al lo l : A n or gani c devel oper agen t for ph otogr aph i c fi l ms.

Oth er n ames u sed ar e pyr ogal l ol , pyr ogal l i c aci d or

tr i h ydr ox yben z en e. It offer s an ex cepti on al ton al r an ge an d

i n cr ease s h i gh l i gh t separ ati on . Pr yo i s tox i c.

R ag : Th ese ar e ol d r a gs or n ew off -cu t s of cotton fabr i c th at

ar e br oken do wn to mak e paper . R ag th r eads or i gi n al l y c ame

fr om th e l on ger , str on ger fi br es of th e cott on pl an t . A l th ou gh

today, paper i s n ot often mad e fr om th e r ags . H o wever th ey do

make a ver y str on g pa per .

R ati o : Th e r el ati on sh i p bet ween two qu an ti ti es. F or ex ampl e

1 : 3 mean s on e par t water an d th r ee par ts ch emi cal .

R e duc ti o n: Th e a ddi ti on of an e l ectr on or el ectr on s fr om an

atom or a mol e cu l e. Ox i da ti on an d r edu cti on occu r

si mu l tan eou sl y ; a r edu ci n g agen t i s a s u bstan ce wh i ch gi ve s

u p el ectr on s an d beco mes ox i di z ed .

R e fl e c ti o n: For smo oth su r faces th e an gl e of th e i n ci den c e i s

th e same as th e an gl e of r efl ecti on occu r r i n g wh en l i gh t

str i kes th e su r face an d bou n ce s back a t th e same an gl e. For

oth er su r faces th e l i gh t i s r efl ec ted back at di ffer en t an gl es,

i . e. scatter ed.

R e fr ac ti o n: Wh en l i gh t pass es th ou gh on e me di u m to an oth er

a r ay i s ben t sh ar pl y at th e su r f ace bet we en th em. In a pr i n t

th i s affect s th e ap pear an ce of th e si l ver wh en th e gl o ssi er

1 0 4

al bu men r efr act s th e l i gh t . Th e pr i n t appear s dar ker i n th e

sh ado ws an d l i gh ter i n th e h i gh ligh ts th an sal ted paper pr i n ts.

S atur ate d S o l uti o ns: A ch emi cal i s added to l i qu i d u n ti l some

i t i s l eft u n di s sol ved . If th e l i qu i d can n ot abs or b or di s sol ve

an ymor e of th e ch e mi cal , i t i s sa tu r ated. A h i gh er temper atu r e

may cau se th e ch e mi cal to di ssol ve bu t a s i t cool s a

pr opor ti on of i t may pr eci pi ta te . Potas si u m di ch r o mate i s

often u sed as a sa tu r ated sol u ti o n .

S e l f-mask i ng : Th e th i n n er ar ea of th e n egati ve al l o ws th e

si l ver ch l or i de con ver t t o metal l i c si l ver i n th e pr i n t. Th i s n o w

dar ker su r face of th e sal t th u s f or ms a „ mas k‟ . Th e ex p osi n g

l i gh t i s h el d back fr om r each i n g th e u n r edu ced si l ver ch l or i de

u n der n eath . M ean wh i l e th e r est of th e sal t pr i n t con ti n u es to

ex pose u n d er th e mor e den se par ts of th e n egati ve.

S e nsi to me tr y: Th i s seeks to e st abl i sh a r el ati on sh i p between

ex posu r e an d th e den si ty of ph ot ogr aph i c mater i al .

S i z i ng : Th e su bst an ce added t o paper to i n cr ease su r face

str en gth . It r esi sts th e pen etr ati o n of sol u ti on s i n to th e fi br es

of th e paper . Gel ati n an d star ch ar e th e most co mm on type s of

si z i n g.

S te p We dg e : Th i s i s ei th er a tr an spar en t fi l m or paper wi th

den si ty i n cr emen t s of 0 . 1 5 or 0.3 0 . A wedge of 2 1 steps wi th

den si ty u n i ts of . 1 5 step i n ter val s gi ve a total r an ge of 3 . 05

den si ty u n i ts. B y cou n ti n g th e nu mber of di sti n ct steps i n th e

pr i n t an d mu l ti pl yi n g by th e . 15 den si ty i n ter val between th e

steps gi ve s th e ex po su r e r an ge i n l ogar i th mi c u n i ts. To

con ver t th i s r an ge t o st ops, m u l ti pl y th e l og u n i ts b y 3 . 3

(Ctei n , 1 9 9 7 ). Oth er n ames:

S ee step tabl et, opti cal wedge an d tr an smi ssi on gr ey s cal e.

We tti ng Ag e nt : A pu r i fi ed deter g en t u sed i n th e fi n al wash i n g

stage of fi l m pr oces si n g , cau si n g to water r u n s to off even l y ,

th u s r edu ci n g r u n mar ks an d wat er spots.

1 0 5

R E F E R E N C E S

A n ch el l , S . G. (20 0 0 ) T h e Dar k r oom C ook b ook , Focal Pr ess, Woben M . A . US A .

B ar n i er , J. (2 00 0 ) C omi n g in to Foc u s A Step b y Step Gu i d e to Al t er n a ti ve Ph ot ogr a p hi c Pr i n tin g P r oc esses, Ch r on i cal B ooks L L C, S an Fr an ci sco Cal i for n i a US A . B u r kh ol der , D . (1 9 99 ) Ma ki n g Di gi ta l Nega ti ves, B l aded Ir i s

Pr ess US A , Car r ol l ton . Cl er c, L . P. (1 9 44 ) P h ot ogra p h y Th eor y a n d P ra c tic e, Hen r y Gr een wood & Co, . L TD , L on don . Cr awf or d, W. (1 9 7 9 ) K eep er s of the Li gh t, M or gan & M or gan , In c. , New Yor k, US A . Ctei n (1 9 9 7 ) P ost Ex p osu r e - Ad van c e T ec h n i qu es for th e

P h ot ogr a p h ic Pr i n t er, B u tter wor th -Hei n eman n , Wobu r n M A US A . E der , J. M . (1 9 78 ) Hi stor y of P h otogr a p h y, D over Pu bl i cati on s In c Ne w Yor k. Far ber , R . (1 99 8 ) H i stor i c P h otogra p h ic P r oc esses: A G u i d e to

C r ea ti n g H a nd ma d e Ph otogr a p hi c I ma ges, A l l wor th Pr ess, Ne w Yor k. Gr ay, M . , Ol l man , A. an d M cCu sker , C. (20 0 2 ) T h e Fi r st

P h ot ogr a p h s Wil l i a m H en r y Fox Ta l b ot an d th e Bir th of P h ot ogr a p h y, Power Hou s e B ook s US A , New Yor k. Hu tch i n gs, G. (1 9 92 ) Th e Book of P yr o, B i tter D og Pr ess, Gr an i te B ay, CA . James, C. (2 0 0 2 ) T h e Book of Al ter n a ti ve Ph otogr a p hi c P r oc esses, D el mar , New Yor k.

Jen kyn - Jon es, B . (1 9 8 8 ) Un i ver si ty of Ox for d. Jon es, B . E . (1 97 4 ) Enc yc l opa ed i a of P h otogr a p h y, A r n o Pr ess In c. , US A . L avedr i n e, B . (2 0 03 ) A G ui d e to t he P r even ta ti ve C on ser va ti on

of P h ot ogr a p h ic C ol l ec ti on s, Th e Getty C on ser vati on In sti tu te, L os A n gel es US A . Nel son , M . I. (2 00 4 ) P r ec i si on Di gita l N ega ti ves: For Si l ver & Oth er Al ter n a ti ve P r oc esses, M ar k I Nel son .

R ei l l y, J. M . (1 9 80 ) Th e Al b u men & Sa l te d P ap er Book : Th e H i stor y a nd pr a c ti c e of p h otogra ph i c pr i n tin g, 1 84 0 - 1 8 95 . , L i gh t Impr essi on s C or por ati on . , R och ester , US A . R ei l l y, J. M . an d K en n edy, N. (19 84 ) P h otogr ap h i c Sc i en c e a nd

En gi n eer i n g. Vol . 2 8 , N u m. 4 , 2 8 , p. 1 6 6 -7 1. S ch aaf, L . J. (1 9 96 ) Rec or d s of th e Da wn of P h otogr a ph y

T a l b ot' s Not eb ook s P & Q, Un i ver si ty Pr ess Ca mbr i dge, Cambr i dge Gr eat B r i tai n . S ch aaf, L . J. (2 0 00 ) Th e P h otogr aph i c Ar t of Wi ll i a m H enr y Fox

T a l b ot, Pr i n ceton Un i ver si ty Pr ess, Ox for dsh i r e, UK . Tu r n er , S. (19 9 8 ) T h e Book of Fi n e P a p er s, Th ames an d Hu dson In c, Ne w Yor k. Wal l , E . J. an d Jor dan , F. I. (1 97 5 ) P h otogr a p hi c Fac ts a nd

For mu l a s, A mer i can Ph otogr aph i c B ook Pu bl i sh i n g Co. , In c. , New Yor k US A . Wal l s, H. J. an d A ttr i dge, G. G. (19 7 7 ) Ba si c Ph oto Sc i en c e, h ow p h otogr a p h y wor k s, Focal Pr ess, L on don . War e, M . J. (19 94 ) Mec ha n i sm of Ima ge Deter i or a ti on i n Ear l y P h ot ogr a p h s - th e sen si ti vi ty to Ligh t of WH F T a lb ot' s

1 0 6

h a l i d e - fix ed I ma ges 1 8 34 - 18 44 , Sci en ce M u seu m an d Nati on al M u seu m of Ph otogr aph y, Fi l m & Tel evi si on , B r adfor d, L on don .

War e, M . J. (20 03 ) H i stor y of P h otogr a p h y, 27, 35 -3 9 . War e, M . J. (20 06 . ) G ol d i n Ph otogr a p h y., ffotoffi l m pu bl i sh i n g, B r i gh ton , UK . Webb, R . an d R eed, M . (2 0 00 ) Al ter n a ti ve Ph otogr a p hi c

P r oc esses : A Wor k i n g G u i d e for Ima ge Ma k er s, S i l ver Pi x el Pr ess, R och ester N Y US A .

1 0 7

A T T A C H M E N T 1 CD: M IS C E L L A N E A P H O T O GE N I C A

1 0 8

A T T A C H M E N T 2 T H E S A L T P R I N T M A N U A L

1 0 9

MECHANISMS OF CONTROLLING COLOUR AND AESTHETIC APPEARANCE OF THE PHOTOGRAPHIC SALT PRINT.

Eleanor (Ellie) Young

A thesis submitted in fulfilment of the requirements for the degree of Master of Applied Science (Photography)

School of Applied Sciences Portfolio of Science Engineering and Technology

RMIT University February 2008

The following images are a pictorial illustration of the results of the research carried out in the attached thesis An exhibition of many of these works are displayed at Photospace 34 Dight Street Collingwood Victoria from the 27th of February to the 22nd of March

All work was photographed on an 8 x 10 camera using FP4 black and white negative film and PMK developer . Each of the images are contact printed using various, formulas, binders, papers and toning methods to illustrate the different colours and effects that can be achieved.

Exhibition Title: Miscellanea Photogenica

Miscellanea Photogenica

Title: Chinese Lantern #2 Paper: Saunders HP 120 gsm Solution: Arrowroot Toner: Gold borax and palladium

Title: Chinese Lantern#1 Paper: Bergger COT 320 gsm Solution: Ammonia Chloride, Sodium Citrate and gelatine Toner : Gold borax and platinum

Miscellanea Photogenica

Title: Love in the mist #1 Paper: Talbot 240 gsm Solution: Sodium Chloride and Gelatin Toner: Gold acetate and palladium

Title: Love in the Mist #2 Paper: Talbot 240 gsm Solution: Ammonium chloride and gelatin Toner: Platinum

Miscellanea Photogenica

Title: Love in the Mist #3 Paper: Arches Platine HP 310 gsm Solution: Sodium Chloride and gelatin Toner: Gold borax and platinum

Title: Love in the Mist #4 Paper: Buxton 240 gsm Solution: Albumen Toner: Gold acetate and palladium

Miscellanea Photogenica

Title: Scotch thistle # 3 Paper: Berrger 320 COT Solution: Ammonium Chloride sodium citrate and gelatin Toner: Gold borax

Title: Scotch thistle # 2 Paper: Berrger 320 COT Solution: Ammonium Chloride sodium citrate and gelatin Toner: Gold borax

Title: Scotch thistle # 1 Paper: Berrger 320 COT Solution: Ammonium Chloride sodium citrate and gelatin Toner: Gold borax

Miscellanea Photogenica

Title: Daisy Face Paper: Berrger 320 COT Solution: Ammonium Chloride and gelatin Toner: Gold borax and platinum

Title: Gum Leaves Paper: Berrger 320 COT Solution: Ammonium Chloride sodium citrate and gelatin Toner: Gold borax and platinum

Miscellanea Photogenica

Title: Snail Paper: Saunders HP 140 gsm Solution: Arrowroot Toner: Gold Acetate and pallatinum

Title: Shell #3 Paper: Arches Platine 310 HP Solution: Sodium chloride Toner: Gold Thiocyanate (No 2)

Miscellanea Photogenica

Title: Shell #1 Paper: Berrger 320 COT Solution: Ammonium Chloride and gelatin Toner: Gold acetate and platinum

Title: Shell #2 Paper: Berrger 320 COT Solution: Ammonium Chloride and gelatin Toner: Gold thiocyanate (no1)

Miscellanea Photogenica

Title: Wing #1 Paper: Arches platine 310 HP Solution: Arrowroot Toner: Gold acetate and palladium

Title: Wing #2 Paper: Fabriano artistico Solution: Albumen Toner: Gold thiocyanate

Miscellanea Photogenica

Title: Wing #4 Paper: Saunders HP 140gsm Solution: Arrowroot Toner: Gold acetate and platinum

Title: Wing #3 Paper: Arches platine 310 HP Solution: Albumen Toner: Gold Borax

Miscellanea Photogenica

Title: Strawberry Paper: Fabriano Artistcio Solution: Arrowroot Toner: Gold Acetate and platinum

Title: Pear Paper: Buxton 240 Solution: Albumen Toner: Gold Borax

Miscellanea Photogenica

End

SALT PRINTING MANUAL

SALT & ALBUMEN PHOTOGRAPHIC PRINT PROCESS ES BY ELLIE YOUNG

THE SALT PRINTING MANUAL

A GUIDE TO SALT AND ALBUMEN PHOTOGRAPHIC PRINT PROCESSES

g ol d s t re e t st u d io s

7 0 0 J a me s L a n e V i c t o ria 3 4 5 8 A u s t ra l ia

P hon e 6 1 3 5 4 2 4 1 8 3 5 • Fa x 6 0 3 5 4 2 4 1 8 3 5

www. g o l ds t ree t s t ud ios . co m .a u

injury, sickness, damages or

The author and publisher of this manual deny any liability for any consequent loss from using the information contained within this text

CONTENTS

A C K N O W L E D G E M E N T S ................................................................ .............. V I N T R O D U C T I O N ................................................................ ..................... V I

1.

T HE O RI GIN S ............................................................................. 1

2.

P HO T OGR A P HI C PR OC E S S ES ........................................................ 4

A L T E R N A T I V E P H O T O G R A P H I C P R O C E S S E S ................................ ...................... 4 P H O T O G R A P H I C P R I N T P R O C E S S E S . ................................ .............................. 4 M A T T E R S U N I Q U E T O S A L T P R I N T I N G ................................ ........................... 6

3.

PR E PA RIN G FO R SA L T P RIN TIN G .................................................. 8

T H E W O R K I N G S P A C E : ................................................................ ............. 8 E Q U I P M E N T : ................................................................ ......................... 8 T O O L S A N D M A T E R I A L S ................................................................ ............ 9 C H E M I C A L S ................................................................ ........................ 10 O V E R V I E W O F T H E S A L T P R I N T I N G S T E P S ................................ ..................... 11

4.

T HE S A LT A N D S I LV ER F ORM UL A S ............................................... 13

S odium Ch lo ri de F or m ul a. .............................................................. 13

Ammon ium Ch lo ri de Fo r m ula. ................................ ......................... 13

V A R I A T I O N S T O S A L T F O R M U L A S ............................................................... 14 A D D I T I V E S T O S A L T F O R M U L A S ................................................................ . 15 S O D I U M C I T R A T E ................................................................ ................. 15 S odium o r Am moni um C hlo ride + S o di um Ci tr ate .............................. 16

P O T A S S I U M D I C H R O M A T E ................................................................ ....... 16 Pota ss ium D ic h romat e 5 % S o lut ion ................................ ................. 17

S odium o r Am moni um C h lo ride + Pot as s ium Dic hrom ate ................... 17

B I N D E R S ................................ ................................ ............................ 17 G E L A T I N B I N D E R ................................................................ .................. 18 S odium o r ammo nium c h lor ide so lut ion + ge lat in ............................. 18

A R R O W R O O T B I N D E R ................................................................ ............ 19 Ar ro w roo t fo rmu la ................................................................ ........ 19

A L B U M E N B I N D E R ................................................................ ................ 20 Albu men fo rmu la ................................................................ ........... 21

S I L V E R N I T R A T E S E N S I T I S E R ................................................................ ..... 22 S ilv er N it ra te S en s iti s in g Fo rm u la ................................ ................... 23

S ilv er N it ra te Fo rm u la w ith Ci t ric Ac id ................................ ............ 25

5.

T HE P A P ER ............................................................................... 26

P A P E R M A N U F A C T U R I N G ................................................................ ........ 26 A D D I T I V E S T O P A P E R ................................................................ ............. 27 S U R F A C E F I N I S H I N G ................................................................ .............. 28 W E I G H T A N D D E N S I T Y ................................................................ ........... 28

ii

C A R E O F P A P E R ................................................................ ................... 29 P A P E R S F O R S A L T P R I N T I N G : ................................................................ .... 29 A D D I N G S I Z I N G T O P A P E R ................................................................ ....... 32 Ge lati n S iz ing ................................................................ ............... 32

H A R D E N I N G T H E G E L A T I N S I Z I N G : ............................................................. 33 Gl yo xal Ha rden ing Fo rm ula ............................................................ 34

6.

CO A TIN G TH E P A P ER ................................................................. 35

P R E P A R I N G T H E P A P E R ................................................................ ........... 36 C O A T I N G L I G H T W E I G H T P A P E R S A N D F A B R I C : ................................ ............... 36 S A L T C O A T I N G ................................................................ .................... 37 A L B U M E N C O A T I N G ................................................................ .............. 39 S E N S I T I S I N G T H E P A P E R ................................................................ ......... 40 S E N S I T I S I N G A L B U M E N P A P E R ................................................................ .. 41 S E N S I T I S I N G A R R O W R O O T P A P E R .............................................................. 42

7.

P HO T OGR AM S AN D T H E N E GA T IV E .............................................. 43

P H O T O G R A M S ................................................................ ..................... 43 T H E S A L T P R I N T N E G A T I V E ................................................................ ...... 44 T Y P E S O F N E G A T I V E S : ................................................................ ............ 45 A N A L O G U E C O N T I N U O U S T O N E F I L M N E G A T I V E S ................................ ........... 45 PM K D eve lope r ................................................................ .............. 46

I N C R E A S I N G T H E T O N A L R A N G E P O S T D E V E L O P M E N T ................................ ....... 48 E N L A R G I N G N E G A T I V E S I N T H E D A R K R O O M ................................ ................... 48 D I G I T A L N E G A T I V E S ................................................................ .............. 49

8.

EX P OS IN G T H E PR IN T ................................................................ 53

E X P O S U R E T I M E S ................................................................ .................. 55 R E C I P R O C I T Y F A I L U R E ................................................................ ............ 55 S E L F M A S K I N G ................................................................ .................... 56 B R O N Z I N G ................................ ......................................................... 56

9.

PR OC E S S IN G TH E P RIN T ............................................................. 59

P R E - W A S H ................................ ......................................................... 60 T O N I N G ................................ ............................................................ 61 Gol d B o rax To ne r ................................................................ .......... 62

S odium Ac et ate Go ld To ner . .......................................................... 62

Th ioc ya nate Go ld Ton e r 1. .............................................................. 63

Th ioc ya nate Go ld Ton e r 2 ............................................................... 63

Pall adi um Tone r ................................................................ ............ 65

T H E F I X E R ................................ .......................................................... 67 Fi xe r ................................ ............................................................ 68

Kodak F ixe r Te st S olu tio n F T 1 ......................................................... 69

W A S H I N G T H E P R I N T ................................................................ ............. 70

iii

T H E C L E A R I N G A G E N T ................................................................ ............ 70 Cle a ring Age nt ................................................................ .............. 70

T H E F I N A L W A S H ................................................................ ................. 71 Kodak Hy po Te st S o lut io n H T1a ................................ ....................... 72

Kodak hyp o te st ht -2 ................................................................ ..... 73

D R Y I N G ................................ ............................................................. 74

10 .

ST OR A G E AN D F RA M IN G ............................................................ 75

S T O R A G E ................................ ................................ ........................... 75 F R A M I N G ................................ ................................ ........................... 76

11 .

PR OB L EM S ............................................................................... 79

GL OS S AR Y ........................................................................................ 82

A PP EN D IX 1 C H E M I CA L S ..................................................................... 86

S A F E T Y N O T E S ................................................................ ..................... 86 M E A S U R I N G O U T C H E M I C A L S : ................................................................ .. 87 C O N V E R S I O N S O F M E A S U R E M E N T S ............................................................. 87 C H E M I C A L S U S E D I N T H I S M A N U A L ................................ ............................ 88

A PP EN D IX 2 M A T ERI A L SU P PL I ER S ....................................................... 96

C H E M I C A L S A N D A L T E R N A T I V E P R O C E S S K I T S ................................ ................ 96 E X P O S U R E F R A M E S : ................................................................ .............. 96 S H E E T F I L M : ................................................................ ....................... 96 G L A S S R O D C H E M I C A L S P R E A D E R S : ................................ ............................ 96 P A P E R S U P P L I E R S : ................................................................ ................ 96 S T E P W E D G E S ................................................................ ..................... 97

B IB L IO GR A P HY ................................................................................. 98

iv

AC K N OW L ED G EM E NT S

M a n y peo p le ha v e c on t ri b u t e d t o t his m a n ua l in va r io u s wa ys .

I wo u l d li ke to m y exp res s g ra ti t u de to M ic h a el a n d Ba r ba ra Gr ey fo r t he in i tia l i n t r od u c t ion to sa l t p rin t in g in 1 9 9 9 .

fo r

t he “ ma n ua l ” p h o to g ra p h e r. T ha n ks

Als o wi s h t o t ha n k a n d a c kn o wl e dge A sso cia t e P r ofe ss o r Ga le Sp r in g , P r og ra m L e a de r S cie n t if i c P ho to g ra p h y RM IT , fo r h is a ssi st a n c e a n d t i re l ess s u pp o r t. I a m gra t ef u l t o Ala n E ll io t t fo r hi s gen e ro u s a n d en t h us ia s t ic a ss is ta n ce a t s o ma n y l e vel s . D r M ic ha el W a r e , w h ose a ssi s ta n c e a s a n on g oin g in va l ua bl e con s ul ta n t wa s t r ul y a p p re cia t ed . I a l s o a m d ee pl y g ra tef ul to P hi li p F ra n ce s o f t he RM IT P h ys i cs De pa r t men t , J a me s R e ill y , T ris h a n d Wa r ren Si mp son o f Si m ps on G ra p h i cs , P h re d Pe te r son Sen i o r L e c t u re r Ap p lie d Sc ie n ce P ho t og ra p h y R M I T t he g en e r o us a n d L u t he r H u be r o f B on d I ma gi n g (K o da k ) Ne ga ti ves . D a n i elle sp on s o rs hi p o f t h e D u ra clea r Ed wa r ds t o A n t h on y M o u rn a in of P ho t o Fo r m ula r y , S u za n n e G reg o r y a n d Ro be r t L ove fo r t hei r a ssi s t a n ce wi t h t h is ma n u a l .

I a m in de b te d t o a ll t he s t u den ts wh o ha v e a t ten de d m y wo r k s h op s; t h ei r q ue r ies h el pe d e x ten d m y kn o wl ed ge of t he p ro ce ss . A la n , m y so ul - ma te a n d li fe t i me pa r tn e r , t ha n ks fo r t he en d less s u p p o r t a n d j us t be in g t he r e.

v

I N TR O D U C TI O N

T he sa l t p rin t i s t h e f o un da ti on of p ho t og ra p h y. M y in t e res t

in t h is p r o ces s wa s in i tia t ed b y a sa l t p rin t in g wo r k s h op in M el bo u rn e, A us t ra l i a , r u n b y M i c ha e l G r ey , t h en c u ra t o r of t he Fox Ta l bo t M us e u m in L a c oc k , En g la n d. Wi ll ia m H en r y Fox Ta l bo t , kn o wn a s t h e “fa t he r ” o f p h o to g ra p h y , di sc o ve re d t he sa l t p r in t p r o cess i n 1 8 3 4 . T he h is t o r y o f Ta l b o t is q ui te re ma r ka b le . Hi s ea rl y d is co ve r ies we r e t he f o un da ti on o f n u me r o us p ho t og ra p hi c a n d p r in t p r oc esses , ma n y s ti ll p ra c tis ed t oda y .

Sa l t p r in tin g is a h a n d - c oa te d t wo -s te p pr o ces s . F i rs t , t h e sa l t so l u ti on is a p pl ie d t o t h e pa pe r a n d a l lo we d t o d r y . N ex t is t h e sen s i ti sin g st ep , a sil ve r n i t ra t e sol u t ion , is a p pl ie d to t he pa pe r t o f o r m li gh t s en s it iv e si lve r c hl o ri de . Ex po s u re t o lig h t c ha n g es t he si lve r c hl o ri de to t he i ma ge ma k in g me ta l li c sil ve r . T hi s sa me p r oc ess o c c u rs in a l b u men p rin t in g . A l b u men ha d a n en o r m o us i m pa c t on p h o to g ra p h y b ec o m in g t he me d i u m o f c h oi ce d u ri n g t he la s t ha lf o f t he 1 9 t h c en t u r y. Wh il e of ten t rea t ed a s a di ffe r en t p r oc e ss , a n a l b u m en p r in t is essen t ia l ly a sa l te d pa pe r p r in t usin g t h e a lb u m en a s a b in d er .

D ue t o t he in he ren t ma sk in g a bi li t y n o ot h e r p h o to g ra p hi c

p rin t p ro ce ss ca n c r ea t e t he t on a l ra n ge o f t h e sa l t p rin t . T he c ha l len ge is to c rea te n e ga ti ves t ha t re a c h t his e xt r a o r din a r y ra n ge . T he sa l t p ri n t a l so o ffe r s fl exi b il it y in co n tr ol lin g t h e co lo u r , ton e s a n d h ue s.

Ex ce p t wh e re s ta t e d, a ll t he me t h o ds , fo r m u la s a n d p r o ce d u res ha v e been te s te d b y t he a u t h o r. U l t i ma te l y t h e in t en ti on of t h is ma n ua l is to p ro vi de a re so u r ce t ha t wi ll e n co u ra ge f u r t h er exp lo ra t ion of sa l t p rin t in g .

vi

CHAPTER 1

1. T H E O RIG I NS

S i nc e A r is to tl e 1 (3 8 4 -3 2 2 B C) t he re is e v i de n ce t h a t me n a n d w o me n h a v e be e n e x p lo r i ng t he re l a t io ns h i p be tw ee n l ig h t a n d c he m i c a ls . Re m a r k a b l y i t to o k u n t i l 1 8 3 4 b e fo r e W i l l i a m He nr y Fo x T a l bo t d is co v e r e d t he pro c es s o f pe r m a ne n t ch e m i c a l ly p ro d uc e d i m ag es cr e at e d b y l ig h t . H is s a l te d - p a pe r p ri n ts w ere t he f irs t p ho to g r a p h i c p ro ces s t h a t cr e at e d a po s i t i ve i m ag e „ p ho to g e n i c dr aw i ngs ‟ a n d h is fro m a n eg a t i ve . T a l bo t ‟s e f f e c t o n b o t h co n t i nu a l d is co ve r ies h a d a p ro fo u n d p ho to g r a p hy a n d t h e d e ve lo p me n t o f pr i n t m a k in g.

Wil lia m Hen r y F ox Ta l bo t ( 1 8 0 0 - 1 8 7 0) ca me f ro m a p ri vi le ged ba c kg r o un d . He wa s wel l e d u ca te d , wi t h a b r il lia n t m in d a n d c u ri o us a b o u t t he wo rl d a r o un d hi m . F o r t un a te ly f o r t he hi s to r ia n s a n d p h o to g ra p hi c resea r c h er s Ta l b ot do c u m e n te d m os t o f h is ex pe r i m en t s. 2

c rea te

t o

a n

la yin g

In I ta ly 1 8 3 3 , Ta l b ot wa s on h ol ida y wi t h hi s n e w wif e a n d fa mi ly m e m be rs . H e be ca me f r us t ra te d wi t h h is in a b il i t y to ske t c h on pa pe r 3. E v en wi t h t he a i d o f h is d ra win g in s t r u m e n t , a ca m e ra l u ci da , he c o ul d n o t ca p t u re t he b ea u t y of L a k e C o mo . U ti li sin g hi s kn o wl e dge o f c he m is t r y he p on d e re d wa y s o f “ fi xin g ” a n i m a ge on pa pe r . B y s p r i n g 1 8 3 4 Ta lb o t ‟s pon de r in g s be ca me r ea l i ty . He fo un d t he ra ti o b et we en s a l t a n d s il ve r n i t ra te t ha t wa s essen t ia l a n d i ma ge. „s ta bi li se ‟ Ta l bo t ‟s dis c ov er y of t he sa l t p rin t in s pi re d yea r s of re sea r c h, t he fo un da ti on f o r ma n y f u t u re p rin t p ho t og ra p h ic p ro ce sse s . In 1 8 3 9 wi t h t he a ssi s ta n c e

1 E d e r , J . M . ( 1 9 7 8 ) H i s t o r y o f P h o t o g r ap h y , D o v e r P u b l i c a t i o n s I n c N e w Y o r k . p 1

2 S c h a af , L . J . ( 2 0 0 0 ) T h e P h o t o g r ap h i c A r t o f W i l l i a m H e n r y F o x T a l bo t , P r i n c e t o n U n i v e r s i t y P r e s s , O x f o r d s h i r e , U K. p .2 9 .

3 I b i d . p 1 3 .

T he Sa l t p ri n t M a n u a l | 1

T he O rig in s

of h is c ol lea g ue , S ir J o hn He rs c he l, T a lb o t wa s a b le t o „ fix ‟ t hi s i m a ge p e r ma n e n tl y on pa pe r . D es pi te t his , i ma g e f a din g st il l ca us e d T a l bo t a gr ea t dea l of g r ief t h ro u g h in a de q ua te p ro ce ssin g a n d wa sh in g . Fa din g be ca me s u c h a n i ss ue fo r ma n y sa l t p rin t e rs t ha t a fa din g co m m i t tee wa s es ta bli s he d in 1 8 5 5 .

t h e m

li g h t sen s i ti v e pa pe r; a n

T he p h o to g ra ms , o r a s Ta l bo t c a ll ed „ p ho t og e n ic d ra wi n gs ‟ we r e c re a te d b y coa t in g wr it in g pa pe r wi t h a sa l t (s od i u m c h lo r i de ) s ol u ti on . Af t e r t h e p a pe r d rie d he a p p li ed a coa t in g of s il ve r n it ra t e so l u ti on . An ob je c t su c h a s a lea f o r la ce wa s p la c ed on t he d r y , n o w i m a g e wa s c rea te d wh en ex p o sed to s un li g h t. T hi s is a sa l t p ri n t o r sa l t ed pa pe r p rin t . I n 1 8 3 4 Ta l bo t bega n ex p os i n g i m a ge s in a ca m era . B y con ta c t p rin t in g t he se n e ga ti ve sa l t p rin t s, Ta l bo t p ro d u ce d po si ti ve i ma ges .

t he

en o r m o us

t h a t ga ll i c a c i d In 1 8 4 0 he d is c ove r ed de vel o pe d o u t a la ten t i ma ge o n pa p e r . T h is c rea te d to po si ti ve f i rs t dev el op ed -o u t n ega ti ve p ho t og ra p h ic p rin t p r oc ess . Ex po s u r e ti me in t he ca me ra d ra ma t ica ll y de c rea sed f ro m h o u rs to sec on ds 4. T he e ff ec t on p ho t og ra p h y ‟s a n d re p r od u c ti ve po we r wa s effe c t ive l y wa s t he de m ise o f t he Da g u er re o t y pe . 5

f la s h a n d

in f ra re d p h o t og ra p h y . H e se t

As ea rl y a s 1 8 4 2 Ta l bo t p r o po se d t h e t ele p h o to len s, ele c t ron ic t h e fo un da ti on of p h o t og ra v u re wi t h p ho t o en g ra vin g , p r e di c t in g p ho t og ra p h ic r ep r od u c t ion wo u l d f oll o w t h e wa y o f t he p rin t in g p re ss 6. Ta l bo t wa s o bses se d wi t h t he po we r of l ig h t . T hi r t y- t wo o f h is f o r t y- t wo p u b li s he d p a pe rs dea l t wi t h l ig h t . 7

t he n i n e teen t h c en t u r y . Ta l bo t ca me

T he o u t st a n d in g s c ho la r, ex pe ri m en t er , t hin ke r a n d a r ti s t wa s de s tin e d to be c o me on e of t he m os t in f l ue n ti a l sc ien ti s ts of in t o

4 E d e r , J . M . ( 1 9 7 8 ) H i s t o r y o f P h o t o g r ap h y , D o v e r P u b l i c a t i o n s I n c N e w Y o r k . p 3 2 1

5 I b i d . p 3 2 3

6 S c h a a f , L . J . ( 2 0 0 0 ) T h e P h o t o g r a p h i c A r t o f W i l li am H e n r y F o x T a lb o t , P r i n c e t o n U n i v e r s i t y P r e s s , O x f o r d s h i r e , U K. p 2 8

7 G r a y , M . , O l l m a n , A . a n d M c C u s k e r , C . ( 2 0 0 2 ) T h e F i r s t P h o t o g r a p h s W i l l i a m H e n r y F o x T a l bo t a n d t h e B i r t h o f P h o t o g r a ph y , P o w e r H o u s e B o o k s U S A , N e w Y o r k .

T he Sa l t p ri n t M a n u a l | T he O ri gin s 2

T he O rig in s

p ho t og ra p h y a s a pi c t u re ma k e r r a t h er t ha n a sc ien ti s t 8 c rea tin g a n e w c ra f t a n d a r t fo r m . T he sa l t p rin t e m b ra c es t he a r t, c ra f t a n d sc ien ce of p ho t og ra p h y .

in cl u des

t h e

t o a l b u men p rin t in g ,

c h a n ge d

Sa l t p rin t in g t h e a l b u m e n p rin t in g p ro ce ss . Al b u m en i s t he b in de r o b ta in ed f r o m t he egg wh i t e o f u s ua l ly hen ‟s e gg s . In bo t h s a l t a n d a l b u men i ma ge . T h e F r en c h f o r ms p rin t in g s i lv er c hl o ri d e p ho t og ra p he r L o u i s Dés i ré B la n q ua r t -Ev ra r d d eve lo pe d t h e a lb u m en p rin t in t he la te 1 8 4 0s . H e di sc ov e re d t he a l b u men pa pe r wh i l e sea r c h i n g f o r i m p r ov e men ts in Ta l b o t‟ s ca l o t y pe (p a p e r n ega t ive ) p r oc ess . O n M a y 2 7 , 1 8 5 0 B la n q ua r t -E v ra r d p res en te d hi s di sc o ve r y to t he F r en c h Ac a d e m y . B y 1 8 5 5 m os t p ho t og ra p he r s ha d t hi s re ma in e d t h e p rin ci pa l p rin t in g me t h od un ti l 1 8 9 0 when gela t in si lve r ca me in t o use 9.

T he Ge r ma n ci t y of D re sd en , b y 1 8 7 0 s u p pl ie d t h e m a j o ri t y o f t he wo r l d‟ s a l b u m en p a p e r. D res den ha d t he a d va n ta g e o f be in g cl ose t o t h e pa pe r ma n u fa c t u r er s of Ri ve s a n d S a xes . Co m bin ed wi t h a n e xce llen t s u p p ly of l o w c os t eg gs a n d la bo u r t he y p r o d u ce d a su pe ri o r p r o d uc t . In 1 8 8 8 t he D re sd en e r Al b u m u i n fa b r i ken A. G fa c t o r y use d m o re t ha n six m il l ion eg gs to ma ke 1 8 , 6 7 4 rea m s of a l b u me n pa pe r . Ea c h ha n d c ra f te d rea m wa s 4 8 0 s he e ts a t 4 6 0 m m b y 5 8 0 m m . T his wa s j us t on e of se ve ra l f a c t o rie s in D re sd en a l on e . 10

t he i r

f i rs t p h o to gra p h i c

P ho t og ra p he r s to da y ma y n o t be a w a re o f ho w t he e a r ly pi on ee r ‟s ma de i ma ges , b u t con t e m po ra r y p h o t og ra p he rs s t il l s ha re t he sa m e de si re to ma ke pe r m a n en t i ma ges . 11 To da y, a s p ho t og ra p h ic i ma g i n g con t in ues to ex ten d a n d d eve lo p we de ba te a n d s t r ug gl e wit h a m y ri a d of i ss ues of wh a t we be lie ve p ho to g ra p h y s ho u l d be .

8 W al l s , H . J . a n d A t t r i d g e , G . G . ( 1 9 7 7 ) B as i c P h o t o S c i e n c e , h o w p h o t o g r a p h y w o r k s , F o c al P r e s s , L o n d o n . p 1 3

9 E d e r , J . M . ( 1 9 7 8 ) H i s t o r y o f P h o t o g r a p h y , D o v e r P u b l i c a t i o n s I n c N e w Y o r k . p 5 3 5 - 5 3 7

10 R e i l l y , J . M . ( 1 9 8 0 ) T h e A l bu m e n & S a lt e d P a p e r B o o k : T h e H i s t o r y an d pr a c t i c e o f ph o t o g r ap h i c pr i n t i n g , 1 8 4 0 - 1 8 9 5 . , L i g h t I m p r e s s i o n s C o r p o r at i o n . , R o c h e s t e r , U S A . p 3 3 - 3 5

11 W al l s , H . J . a n d A t t r i d g e , G . G . ( 1 9 7 7 ) B a s i c P h o t o S c i e n c e , h o w p h o t o g r a p h y w o r k s , F o c al P r e s s , L o n d o n . p 1 3 .

T he Sa l t p ri n t M a n u a l | T he O ri gin s 3

CHAPTER 2

2. PH OT OG R AP H IC P R O C ES S ES

T h is c h a p t er d is c us s es a l t er n a t iv e pro c e s s es i n ge n er a l . I t lo o ks a t t h e d i f f er en c e b etw e e n p ri n t i ng -o u t a n d pro c es s i ng - o u t p ri n ts a n d co n c l u d e s w i th is s ues u n iq ue to t h e s a l t pr i n t .

A L TE R N A TI V E P H O T O G R AP H I C P R O C E S S E S

bi c h r o ma t es ,

br o m oil s,

M a n y o f t he ea rl y p h o tog r a p h i c p rin t p r oc esse s a re re fe r re d t o a s „ A lt e rn a ti ve ‟ . T h i s te r m a ls o i n c l u de s me t h od s of ca p t u rin g i ma ge s wi t h len s- l ess ca m e ra s s u c h a s pin h ol e . T h e m o re co m m on l y p ra ct i se d p ro ce sse s in c l u d e a l b u men , c ya n o t y pe , gu m zia t y pe , g u m oi ls , pla t in u m /pa lla d i u m , sa l t p rin ts a n d V a n D y ke b r o wn .

De sp i te ma n y de ba te s ov e r t he yea r s , „a l te rn a t ive ‟ i s wi de ly un de rs t oo d a n d a c c ep te d b y t he v a s t m a jo r i t y o f p ra c t it io n er s . Te r ms les s f re q ue n tl y u se d in cl u de ; t ra di t ion a l p ro ces ses , hi s to r ic a l p h o t og ra p hi c p r o ces ses , ha n d c ra f te d i ma ges a n d p ri m i ti ve p ho t og ra p h y .

i ma gin g h a s

la rge l y di s pla c ed

fo r p h o to gr a p h ic p r in tin g ,

t he ma in s ta y

t o da y

f il m ca p t u r e a n d D igi ta l c he m ica l p r oc ess in g. B la c k a n d wh i te silv e r gela t in p ri n tin g , on c e is con si de re d a n a l t er n a t ive p ro ce ss .

P H O T O G R AP H I C P R I N T P R O C E S S E S .

De ve lo pe d - o u t a n d p rin te d -o u t a re t he t wo m a j o r p h o t og ra p hi c p rin t ca teg o ri es .

1. De ve lo pe d , o r p ro ce sse d - o u t, r efe r s t o t he i ma g e t ha t is ca p t u re d b u t n o t s e en un ti l c h e mi ca l b a t hs „ dev el op ‟ o r „p r o ces s ‟ o u t t h e l a ten t i ma ge , kn o wn a s t he c h e mi ca l re d u c ti on o f si lve r pa r ti cl es . M o st p h o to g ra p hi c pa p e rs a re p ro ce sse d in t h e da r k ro o m un de r a re d sa f e li g h t . Sin ce 1 9 0 5 p ro ces s in g - o u t ha s been t he m os t co m m on p ra c ti ce o f p rin t in g . 12 No w di gi ta l o u t p u t s u r pa s se s t he t ra di t ion a l we t p r o c esses .

12 R e i l l y , J . M . ( 1 9 8 0 ) T h e A l bu m e n & S a lt e d P a pe r B o o k : T h e H i s t o r y a n d p r a c t i c e o f ph o t o g r ap h i c pr i n t i n g , 1 8 4 0 - 1 8 9 5 . , L i g h t I m p r e s s i o n s C o r p o r a t i o n . , R o c h e s t e r , U S A . p 2

T he Sa l t p ri n t M a n u a l | 4

D E V E L O P E D-O U T P H O TO G R AP H I C P R I N TI N G

A D V A N T A G E S

D I S A D V A N T A G E S

N e g a t i v e s c a n c r e a t e e n l a r g e d p r i n t s t o a p r e f e r r e d s i z e .

To n a l r a n g e i s n o t a s w i d e a s s o m e o f t h e p r i n t i n g - o u t p r o c e s s e s .

M a s s p r o d u c t i o n s t a n d a r d i s e d c o a t i n g s , a l l o w i n g p r i n t c o n s i s t e n c y .

P a p e r t yp e s a n d s u r f a c e s a r e l i m i t e d t h e b y m a n u f a c t u r e r ‟ s c h o i c e .

P r o c e s s i n g c h e m i c a l s a r e i n a r e a d y t o u s e f o r m .

A t r a d i t i o n a l w e t d a r k r o o m i s r e q u i r e d .

2.

P rin t in g -o u t re fe rs to t he p r oc ess es whe r e p r in ts a re c rea te d b y l ig h t e n e rg y on l y . T he y re q u ir e n o c he m i ca l a i d to p ro d u ce a n i m a g e . M a n y o f t he me t a l ba se d p r o ces ses a p pea r in s ha de s of b ro wn . T h is i s d ue t o t he i ma ge ma k in g pa r ti cle s i ze . T he y a re to o sm a ll fo r l ig h t to re fle c t a l l t h e wa v elen g t h s of li g h t. P r oc esse d o u t sil ve r gela t in a p p ea rs bl a c k a s t he s il ve r pa r ti cl es a re la rge en o ug h t o a bs o r b a l l wa ve len g t h s of li g h t .

A hin g e d b a c k p ri n tin g f r a me a ll o ws e a sy a c ce ss to c h ec k t he ex po s u re d u ri n g p r in tin g . Fo r t h e f i rs t si xt y -f iv e yea rs of p ho t og ra p h y t h is wa s t he m et h o d o f c re a t in g t he ma jo r i t y of p ho t og r a p hi c p rin ts . 13

13 I b i d . p 2 .

T he Sa l t p ri n t M a n u a l | P ho t og ra p h ic P r oc esse s 5

P R I N TI N G- O U T P H O T O G R AP H I C P R O C E S S E S

A D V A N T A G E S

D I S A D V A N T A G E S

Th e c o a t i n g s a r e a p p l i e d b y h a n d , t h e p r i n t s a r e t h e r e f o r e u n i q u e l y t h e p h o t o g r a p h e r ‟ s .

R e s t r i c t e d t o c o n t a c t p r i n t i n g , t h e n e g a t i v e i s t h e s a m e s i z e a s t h e p r i n t . ( A n e x c e p t i o n i s t h e b r o m o i l p r o c e s s )

C o n t a c t p r i n t i n g r e q u i r e s c r e a t i n g n e g a t i v e s e i t h e r b y u s i n g l a r g e f o r m a t c a m e r a s , i n c r e a s i n g t h e n e g a t i v e s i z e i n t h e d a r k r o o m o r p r i n t i n g i n k j e t n e g a t i v e s f r o m d i g i t a l f i l e s .

Th e t o n a l r a n g e i s g r e a t e r t h a n d e v e l o p e d o u t p h o t o g r a p h i c p a p e r s f o r p r o c e s s e s s u c h a s s a l t , a l b u m e n a n d p l a t i n u m / p a l l a d i u m . S o m e h a v e a n a r r o w t o n a l r a n g e , b u t o f f e r b e n e f i t s s u c h a s c o l o u r u s i n g p i g m e n t s . A w i d e c h o i c e o f p a p e r s a n d t e x t u r e s .

E a c h o f t h e p r o c e s s e s r e q u i r e s a s p e c i f i c t yp e o f n e g a t i v e .

Th e n u m e r o u s c o n t r o l s o v e r t o n a l e f f e c t s , c o n t r a s t , s u r f a c e f i n i s h a n d c o l o u r s .

P r i n t i n g - o u t p r o c e s s e s m a y b e o n e , t wo o r m u l t i c o a t i n g s t h a t r e q u i r e d r y i n g b e t w e e n e a c h c o a t b e f o r e e x p o s i n g o r r e - e x p o s i n g .

A d a r k r o o m i s n o t r e q u i r e d .

S u n l i g h t i s a r e a d i l y a v a i l a b l e l i g h t s o u r c e t o e x p o s e p r i n t s .

M o s t s o l u t i o n s n e e d t o b e p r e p a r e d f r o m r a w s t o c k c h e m i c a l s . S o m e r e q u i r e c a r e a n d s p e c i a l h a n d l i n g . S u n l i g h t i s i n c o n s i s t e n t . F o r c o n s i s t e n c y a n a r t i f i c i a l U V l i g h t s o u r c e i s r e q u i r e d .

P r i n t s c a n b e c h e c k e d d u r i n g e x p o s u r e .

E x p o s u r e s a r e c o n s i d e r a b l y l o n g e r t h a n p r o c e s s e d o u t p a p e r s , m i n u t e s t o h o u r s a s o p p o s e d t o s e c o n d s .

M A T TE R S U N I Q U E TO S AL T P R I N T I N G

Sa l t P r in t in g i s a p rin t in g -o u t p ro ces s of fe r in g a ton a l r a n ge gr ea te r t ha n a ll o t h er p h o to g ra p hi c p ri n ti n g p ro ce sse s . T h is i s a t t ri b u te d to a n in he r en t ma s k in g a bi li t y t ha t o cc u r s d u rin g exp os u re . I t r e q ui r es a den se n eg a t i ve wh i c h ma y ex cl u de p rin t in g wi t h o t he r p ro ce sse s . S il ve r n i t ra te s ol u t ion res p o n ds un fa v o u ra bl y t o ma n y pa pe r a d d i ti ves , re st r i c tin g sa l t p rin tin g to q ua li t y 1 0 0 % c ot t on wa t e r c ol o u r pa pe rs . T wo se pa ra te sol u t ion s a re a p pl i ed ; e a c h m us t be d rie d bef o re ex po s u re . An y s h o r t c u ts res ul t in s ta i n in g o r p ro d u cin g a le ss t ha n des i ra ble p rin t .

T he Sa l t p ri n t M a n u a l | P ho t og ra p h ic P r oc esse s 6

is

T he Sa l t a n d Al b u men p r in t c ol o u r a n d a pp ea ra n ce in fl u en ce d b y :

o T he pa pe r : s iz in g in t he pa pe r a n d t he c ol o u r of t h e

pa pe r .

o Ch e mi ca ls : di ff e ren t f o r m ula s a n d a d di ti ve s .

o H u mi di t y .

o The n ega tive or subject ma tter for photogra ms .

o L ig h t ex po s u re s o u r ce .

o Ton in g .

o Wa s hin g a n d fix in g .

A p la in sa l te d p rin t ha s a s in g le la y er st r u c t u re in wh i c h t he i ma ge is e m be d de d in t he p a p e r fi b re . An a l b u m en p rin t , h o we ve r, i s a t wo la ye r s t r u c t u re. Al b u men h ol ds t he i ma g e on t he s u r fa ce of t he p a pe r . 14

T he a d d i ti on of ge la t in a s a bin de r i n t he sa l t so l u ti on ca n a lso c rea te a t wo l a ye r s t r uc t u r e in t he sa l t p r in t. T h e g el a ti n h ol ds t he i ma ge on t he s u r fa ce of t he p a pe r .

14 h t t p / / a r c h i v e . am o l .o r g . a u / c o l l e c t i o n s / 1 / 3 / 1 7 . h t m l

T he Sa l t p ri n t M a n u a l | P ho t og ra p h ic P r oc esse s 7

CHAPTER 3

3. PR EP A RI NG F OR S A L T P R IN T IN G

R eq ui re m e n ts o f t h e w o rk i ng s p ac e , e q u i p me n t , m a te ri a ls a n d in t his c he m i c a ls r eq u ir e d fo r s a l t pr i n t i ng ar e d is c us s e d c h a p te r . I t co n c l u d es w it h a n o u t li n e o f t h e s t e ps i n vo lv e d i n m a k i ng t he s a l t p r i n t .

th ro ug h

C he m i c a ls t h e ms e l v es ar e no t n e ces s a r i l y d a ng ero us , b u t i g no r a n ce c a n c a us e s er io us m is h a n d li ng , o f te n i n j ur ies . T a ke t i me to u n de rs t a n d t h e c he m i c a ls yo u a re us i ng , ho w t he y s ho u l d b e h a n d le d a n d t re a t t he m w i t h t h e u t mo s t res p ec t . A s k t h e c h e mi c a l s u p p li ers o r d o w n lo a d fro m t he w eb M a t er i a ls S a f e ty D a t a S h ee t s ( M SD S) , fo r e ac h o f t h e c h e mi c a ls a cq u ir e d. T h e M SD S gi ves a f u l l des c r i p t io n o f s a f e h a n d l i ng , w ha t pro t e c tio n is r eq ui re d a n d t he fi rs t ai d t re a t m e n t .

tr a d i ti on a l we t da r k r oo m

A is n o t n e ces sa ry . A l t h o ug h des i ra ble , a U V li g h t b ox i s n o t es sen ti a l a s t h e s un ca n s u p pl y t he u l t ra v io le t (U V ) lig h t r eq u i re d to exp ose t h e p r in t . T he c he m ica ls fo r sa l t p rin t in g a n d p r o ces sin g a re re la ti vel y in ex pen s iv e a n d ea sil y o b ta in e d . Ho we ve r s o me c he m i ca l s fo r to n in g a r e c on si de r a bl y m o re c os t ly .

T H E W O R K I N G S P A C E:

o Wo r k ro o m or a rea fo r coa t in g pa pe r wh e r e a l l U V a n d sun li g h t ca n be bl o c ke d o u t . L o w in ca n des ce n t l ig h t in g is r e q ui re d ; 2 5 t o 5 0 wa t t ( lo w wa t ta ge n o r ma l h o us e la mp ) a t lea s t 1 . 5 m a wa y f ro m t h e wo r kin g s u r fa c e . T hi s is wh e re coa t in g a n d in s pe c t ion wi ll ta ke p la ce . N B : Fl uo r es cen t li g h ts s h o ul d n o t be use d a s m os t e m it U V .

o A ben c h o r ta bl e wi t h a d r y c lea n fl a t s u rf a c e f o r coa t in g

pa pe r .

o A we t p r o ces sin g a rea , p r efe ra b l y wi t h r un n in g wa te r , sepa r a t e f ro m t he c oa tin g a n d t he ex p osin g a r ea . T he r e sh o ul d be e n o u g h s pa ce to ho l d 5 t o 8 p ro ce ssin g t ra ys.

o A clea n , d us t f ree d r y l o ca ti on a wa y fr o m wa t e r a n d

c he m ica ls f o r d r y in g fin is he d p r in ts .

E Q U I P M E N T :

o A gla s s s hee t 4 m m to 6 m m t hi c k . Si ze a p p r oxi m a tel y 4 0 0 m m x 5 0 0 m m to p ro vi de a h a r d f la t ba se fo r coa t in g . An a l te rn a ti ve is hea v y ca r d . T his p r o te c ts t he ben c h o r ta ble f ro m in e vi t a b le s il ve r n i t ra te s ta in s .

T he Sa l t p ri n t M a n u a l | P re pa rin g f o r S a lt p rin t in g 8

o D r yin g ca b in e t a n d/ o r ha i r d r ye r to d r y pr in ts .

o Exp os u re f ra me s. T he se ca n be t ra di t io n a l a s t he i ma g e s ho wn , o r a p ie ce o f 3 m m or 4 m m t hi c k gla ss cl ip pe d t o a b oa r d. T he boa r d ca n be hin ge d b y t wo pa r ts ta p ed to ge t he r a s s h o wn . T he b oa r d a n d t he gla s s s h o ul d be t h e sa me si ze , ha ve t he edg es of t he gla ss g ro un d o r ta pe d t o a vo id c u t tin g h a n d s .

o Sca les , ei t he r ba la n ce o r e le c t ron ic , m e a su r in g 0. 1 g m

o r les s.

o A r ti fi cia l U V li g h t s o u rc e o r s un .

T O O L S A N D M A TE R I A L S

o Fo r c oa tin g: G la s s r od s 1 0 m m wi d e r t h a n t he n e ga ti ve . Fo r exa m pl e a 2 0 3 x 2 5 5 m m ( 8 x 1 0 in c h ) n ega t ive re q u ir es a ro d 2 1 3 m m l on g . T h ese a re m a de f r o m a p p rox 1 m m t h ic k wa lle d g la ss t u bes wi t h 1 0 m m op en in g. A t r ia n g u l a r s ha pe a s ill u s t ra t ed wi ll a ll o w coa t in g wh i le us in g on e ha n d.

Al te rn a t iv el y , b r u s h es wi t h n o me ta ll ic pa r ts . D is po sa b le s po n ge b r us he s a re c he a p a n d rea di ly a va i la ble in m u l ti pl e s i zes . B u c kl e b r us he s ca n be ma de wi t h c o t ton wo o l a n d a te s t t u be .

o Sy r in g es 3 m l o r 5 m l t o a cc u ra t el y m ea s u re c oa tin g sol u t ion s ( wi t h o u t t he n ee d le ). C he m i st s h o ps sel l t h e sy r in ge s.

o B ro wn gla ss b o t tl e 1 0 0 m l wi t h a wi de o pen in g f o r t h e

sil ve r n i t ra te s ol u t i on .

o St o ra ge b o t tle s 5 0 0 m l fo r sa l t so l u ti on s.

o Gla s s o r p la s t ic g ra d ua te s 5 0 0 m l a n d 1 0 0 0 ml

fo r ma kin g a n d m ixi n g so l ut io n s .

o Gla s s o r p la s t ic mea su r in g g ra d ua t e o r pi pe t te s 2 5 ml a n d 5 0 m l wi t h a t lea s t 1 m l in c re men t s

o 6 t o 1 0 p ho t og ra p h ic t ra y s , la rg e r t ha n t he p r in t

si ze t o a l lo w r o o m t o m ov e t h e p r in t ea sil y .

o Se t of wo o de n o r p l a st i c p ri n tin g t on gs .

o Clo t h es l in e a n d p lastic pegs or non metallic clips for hanging prints to dry, alte rn a t iv el y n on-metallic screens, fibreglass or plastic for drying prints flat.

o Ro lls o f a bs or b en t wh i t e pa pe r t o we ls to wi pe up s pi lls

a n d ex ces s so l u ti on .

T he Sa l t p ri n t M a n u a l | P re pa rin g f o r S a lt p rin t in g 9

o R ub be r gl o ves fo r ha n d p ro t ec t ion . N ot t he po wd e re d t he m o ff po wd e r ma y ta ke

glo ve pa c ks , a s yo u con ta m in a t e yo u r wo rk a n d wo r k a re a .

o S ma l l s q ua res of pa pe r to we i g h s ma ll e r a m o un ts of

c he m ica ls .

o Pa pe r c u ps fo r mea s u ri n g la r ge r a mo un t s of c h e mi ca ls .

o Pla s ti c sp oon s t o r e mo ve d r y c h e m ica ls f r o m t he i r

con ta in e rs .

o 1 0 0 % Ra g c o t ton wa te r co lo u r pa pe r si z ed wi t h ge la tin o r sta r c h . Se e C ha p t e r 5 T he P a p er f o r m o r e in fo r m a ti on .

o Re m ova bl e ta pe t o h ol d pa pe r s t il l wh i le c oa ti n g .

o Ch eese cl o t h to s t ra in a l b u men a n d a r r o wr o o t s ol u t ion s .

C H E M I C A L S

See A p pen d ix 1 fo r m o re in fo r ma t ion o n t he f ol lo wi n g c he m ica l s .

Sa l ti n g s ol u ti on s

o A m m on i u m c hl o ri de .

o A r ro wr o o t ( f o r s ta r c h bin de r / si z in g ).

o Ci t ri c a c i d ( re q u i re d fo r A r ro wr o o t s ta r c h b in de r ).

o Gela t in ( f o r b in de r / si zin g ) .

o Sil ve r n i t ra t e ( s en si ti se r ).

o So di u m c hl o ri de (sa lt ) .

o So di u m c i t ra te ( in c r ea se s s pee d a n d m o di fie s

co lo u r ) .

o Po ta ssi u m d ic h r o ma te ( to in c rea se c on t r a st ) .

Al b u men P rin t in g

o Egg wh i t e .

o Gla cia l a ce t i c a c id .

Is o p ro p yl Al co h ol 7 0 % ( f o r d o u bl e c oa ti n g) .

o

Ton in g

o A m m on i u m t hi o c ya n a te .

o Ci t ri c a c i d .

o Gol d c hl o ri de 1% .

o Po ta ssi u m c h lo r op la tin i te 2 0% .

T he Sa l t p ri n t M a n u a l | P re pa rin g f o r S a lt p rin t in g 1 0

So di u m a ce ta t e .

o

So di u m c hl o ri de .

o

So di u m c hl o ro pa lla di te 1 5 % .

o

So di u m te t ra b o ra te ( bo ra x ) .

o

So di u m t h io c ya n a te .

o

P ro ce ssin g

So di u m ca r bon a t e ( a d di ti ve to fix e r) .

o

So di u m s ul p hi te (f ix er clea r in g a gen t ) .

o

So di u m t h ios u lf a t e “ h yp o ” (f ixe r ) .

o

D is ti lle d o r de - min era li ze d wa te r s h o ul d be use d to m i x a ll coa t in g a n d ton in g sol u t ion s. C on d i ti o n of p i pes a n d pl u m bin g fix t u re s ma y a l lo w th e wa te r t o p ic k up t ra ce ele m en ts th a t a ffe c t t he c he m ic a l r ea c t ion s d u rin g t he p rin t c oa tin g a n d to n in g p r o cess es . A lt h o ug h t h e q u a li t y of ta p wa te r ca n v a r y gr ea tl y i t is gen e ra ll y s ui ta bl e fo r ma kin g t h e fixe r , s ta n da r d wa s hin g a n d rin sin g o f p r in ts .

O V E R V I E W O F TH E S A L T P R I N TI N G S T E P S

l is t gi ves a ba si c ove r vi e w of t he st ep s

Th e f ol lo win g in v ol ve d in ma kin g a sa l t p r in t .

1 . M a ke t he sa l t so l u ti on .

2 . U se 1 0 0 % c o t to n ra g pa p e r a n d ma r k o u t t he i ma ge a rea .

3 . A pp l y t h e s a l t s ol u t ion to t he pa pe r.

4 . D r y t he sa l t ed pa pe r .

5 . M a ke t he s en si t ise r .

6 . Sen s i ti ze t he p a p e r in s ub d ue d l ig h t .

7 . D r y in s u b d ue d li g h t .

8 . Pla ce n e ga ti ve a n d sec u re in p r in tin g fra m e in s u b d ue d

lig h t .

9 . Exp ose t o U V li g ht .

1 0 . Re m ove p rin t f r o m f ra me in s u bd u ed lig h t .

1 1 . P ro ce ss in s u b d ue d lig h t .

in vo lv e d

in p r o ces sin g t he ex p ose d sa l t p rin t

T he s te ps in c l u de:

1 . P re – wa s h in ta p wa te r in s u b d ue d l ig h t .

T he Sa l t p ri n t M a n u a l | P re pa rin g f o r S a lt p rin t in g 1 1

2 . Wa s h in ta p wa t e r i n s u b d ue d li g h t .

3 . Ton e in s ub d u ed lig h t .

4 . Wa s h in ta p wa t e r i n s u b d ue d li g h t .

5 . Fix b a t h s.

6 . Wa s h in ta p wa t e r.

7 . Hy p o c lea ri n g ba t h .

8 . Fin a l wa s h in ta p w a te r .

9 . D r y .

T he Sa l t p ri n t M a n u a l | P re pa rin g f o r S a lt p rin t in g 1 2

CHAPTER 4

4. T H E S A LT AN D S IL V E R F OR MU LAS

T he b as i c fo r m u l as a re s e t o u t i n t h is c h a p te r , w i t h a n u m b er o f v a ri a t io ns i n c l u d i ng b i n d ers . E a c h c h a ng e o r v ar i a t io n w il l cr e a te a d i f fer e n ce , in s o m e c as es d r a m a t i c d i f f er e nc es w i ll b e o bs er ve d . T hes e a r e t he f irs t s te ps i n co n t ro l li n g t h e co l o ur , to n a l r a ng e a n d t he a es t h e t i c a p p e ar a n c e o f t he s a l t p r i n t.

Ta l bo t u se d so di u m c hl o ri de , o r co m m on ta b le sa l t in his fi rs t sa l te d pa pe r p r in t s. M os t ta ble sa lt s to da y ha ve a t l ea s t so di u m a l u m in o si li ca t e a n d pos si b ly so d i u m io di de . T he se a d di t ive s ma y rea c t wi t h t h e s il ve r n i t ra te , c rea t in g c h e m ica l fog gin g re d u cin g p r in t q u a li t y . P u r c ha se t he s o di u m c h lo r id e fr o m t he l oc a l c h e m ica l s u pp li e r .

( c hl o ri des ) a re n o t

Ple a se No t e: T he sa l t so l u ti on s li gh t sen si t iv e a n d la s t i n de fin it el y . Al l sa l t , a lb u men a n d a r r o w r oo t sol u t ion s ca n be ma de un de r n o r ma l li g h tin g c on di t ion s

SODIUM CHLORIDE FORMULA.

2 5 0 ml 5 g m

D is ti lle d Wa t e r So di u m c hl o ri de M et h o d: 1 . A t r oo m te m pe ra t u re a dd s od i u m c h l o ri de t o t h e di s ti ll ed

wa t er .

is r ea d y f o r us e wh en

2 . T his wil l di sso lv e ea si ly a n d

di sso lv ed .

AMMONIUM CHLORIDE FORMULA.

2 5 0 ml 5 g m

te m pe ra t u re a d d a m m on i u m c hl o ri de

t o

t h e

D is ti lle d Wa t e r A m m on i u m c hl o ri de M et h o d: 1 . A t ro o m

di s til le d wa te r .

T he Sa l t p ri n t M a n u a l | 1 3

is r ea d y f o r us e wh en

2 . T his wil l di sso lv e ea si ly a n d

di sso lv ed .

T he di ff e ren ce s b e t we en t he a m m on i u m c h lo r id e s ol u t ion a n d t he s o di u m c hl o ri d e sol u t ion ; A m m on iu m c hl o ri d e sol u t ion wi l l sli g h tl y d ec r ea se exp os u r e ti m e , en r ic h t he co lo u r a n d con t ra s t o f t h e p r in t m o re t ha n t he s o di u m c h lo r id e so l u t ion . So di u m c hl o ri de is sli g h tl y re dd e r in c ol o u r.

V AR I A TI O N S T O S A L T F O R M U L AS

Sa l t p rin t s a re a t t h ei r b es t wh e n t he c hl o ri d e ( sa l t ) c on te n t i s a p p rox i ma te l y 2 % a n d t he si lve r s o lu t ion is ro un d 1 2 %. Cha n ge s to t h e ra ti o o f sa l t to si lv er c a n be use d t o a l te r t he to n e a n d t he co lo u r of t he fin a l p rin t . Bo t h t h e s od iu m c hl o ri de a n d a m mo n i u m c hl o ri de a r e t he ba se f o r m u la s fo r t he fol lo win g va ria t ion s .

Inc re a se Sal t P erc e nt ag e : Ta l bo t fo u n d t ha t b y in c rea s in g t he sa l t in t he s ol u ti o n , t he pa p e r be ca me le ss li g h t sen s it iv e . T his wa s h is fi r s t a t te m p t a t s ta b il isin g or “ f i xin g ” t he i ma ge s. 15 Ef fe c ts o f in c re a s in g sa lt p er cen ta ge in t h e sa lt sol u t ion ;

o 3 % c rea tes a s li g h t de c rea se in con t ra st a n d t he t on es

a re co ol e r .

o 5 % c rea te s a d ec r ea se i n con t ra s t a n d t he i ma ge a p p ea rs

fla t .

in t h e con t ra s t

o 1 0 % c rea te s a s u bs ta n t ia l d ec r ea se re s ul tin g in a ve r y f la t we a k p r in t.

Dec r ea se t ha t by Sal t P erc en t ag e : Ta l bo t dis co ve re d de c rea s in g t h e sa l t t he re wa s a n in c r ea se in l ig h t se n s i ti vi t y. 16 Ho we ve r , de c rea sin g t h e c h lo r i de s ol u ti on be lo w 1 % ten d s t o p ro d u ce p rin ts la c k in g b r il lia n ce a n d d en si t y . Ef fe c t s of de c rea s in g t he sa l t in t he s ol u t io n t o;

o 1 % ca use s t he sa l t s ol u ti on t o in c re a se t he c on t ra s t a n d

t he ton es be co m e wa r me r in c ol o u r.

15 S c h a a f , L . J . ( 2 0 0 0 ) T h e P h o t o g r a p h i c A r t o f W i l li am H e n r y F o x T a l b o t , P r i n c e t o n U n i v e r s i t y P r e s s , O x f o r d s h i r e , U K.

16 I b i d . p 1 9

T he Sa l t p ri n t M a n u a l | T he Sa l t a n d Sil ve r Fo r m u la s 1 4

t he sa l t s ol u ti on

to fu r t h e r

o 0 . 5% ca us es

in c rea s e con t ra s t, i t be c o m e a wa r m e r co lo u r a n d l ose s s o me de ta il in t he hi g hl ig h ts

o 0 . 2% ca u ses t he sa lt so l u ti on to in c re a se t he con t ra s t a ll o win g in fo r ma t io n in t h e s ha do ws b u t l i t tle in t he hi g hl ig h t s. T he re i s n ot en o ug h f ree c h lo ri de t o r e ma ke t he si lv e r c hl o ri de . T his c yc le n ee ds t o c on tin u e t o ma ke t he me ta ll i c si lve r pa r ti cl es d u r in g t he e xp os u re .

O t he r c h lo r i de sa l t s a re a ls o s ol u b le in wa te r ; t h ese in c lu d e ca l ci u m c h lo r id e a n d p o ta s si u m c hl o ri d e .

I N O R D E R O F W A R M T H O F C O L O U R

I N O R D E R O F L I G H T S E N S I T I V I T Y

1 . A m m o n i a c h l o r i d e

1 . P o t a s s i u m c h l o r i d e

2 . S o d i u m c h l o r i d e

2 . A m m o n i a c h l o r i d e

3 . P o t a s s i u m c h l o r i d e

3 . S o d i u m c h l o r i d e

4 . C a l c i u m c h l o r i d e

4 . C a l c i u m c h l o r i d e

B o t h ca l c i u m c hl o ri de a n d p o ta s si u m c hl o ri d e a re u se d a t t h e sa me 2 % ra t io t o t he d is t il le d wa te r a s t he a m m on i u m a n d so di u m c hl o ri de .

A D D I TI V E S T O S A L T F O R M U L AS

S O D I U M C I TR A TE

So di u m ci t ra t e in c r ea ses t he re d u c ti on of t h e si lve r c hl o r id e a n d sil ve r c i t ra te to me ta ll ic si lv e r on ex p os u re to li gh t . T he re fo re t he p rin ts wi ll be :

o Wa r m e r in c ol o u r .

o L o we r in con t ra s t.

o Exp os e d f o r le ss ti me .

T he Sa l t p ri n t M a n u a l | T he Sa l t a n d Sil ve r Fo r m u la s 1 5

SODIUM OR AMMONIUM CHLORIDE + SODIUM CITRATE

2 5 0 ml 5 g m 5 g m

D is ti lle d Wa t e r Sodium chloride or a mmonium c hloride So di u m ci t ra t e M et h o d: 1 . A t r oo m te m p e ra t u r e a d d t h e c h lo ri d e t o t he di s ti lle d wa te r . is r ea d y f o r us e wh en 2 . T his wil l di sso lv e ea si ly a n d

di sso lv ed .

3 . A dd 5 g m s o di u m ci t ra te ; i t is rea d y f o r use wh e n d iss ol ve d .

T he s od i u m c hl o ri de s ol u t ion wi t h s od i u m ci t ra te in c re a ses t he s pee d b y on e st o p mo r e t ha n a m m on i u m c hl o ri de . T he a m m on i u m c h lo r i d e wi t h s od i u m ci t ra te in t he s ol u ti o n is a bo u t 1 0 % wa r me r i n co lo u r t ha n t he so di u m c hl o ri de .

P O T A S S I U M D I C H R O M A TE

P O T AS S I U M D I C H R O M A TE I S P O I S O N O U S

DU S T FROM T HE D RY CHE MI CAL IS CA RCI NOGE NI C. S KIN CO NT ACT MA Y CAU S E

DE RMA TI TI S. WEA R G LO VE S, E YE P ROTE CTI ON A ND A DU ST MA S K.

A dd in g 2 d ro ps o f po ta ssi u m di c h ro m a te 5% so l u ti on t o 3 0 m l of t he sa l t s ol u t io n yo u wi l l:

In c rea s e t h e c on t ra s t o f y o u r i ma ge .

o

In c rea s e t h e ex pos u re ti m e.

o

Po ta ssi u m d ic h r o ma te be co m es l ig h t- se n si ti ve wh en i t oxi d ise s wi t h t h e gel a t in . I t re d u ces t he l ig h t s e n si ti vi t y t he re fo re re q u ir es l on g er e xp os u re ti m es . 17

17 “ P o t as s i u m d i c h r o m a t e i s o n l y l i g h t - s e n s i t i v e w h e n i t h a s s o m e t h i n g t o o x i d i s e f o r e x am p l e g u m A r ab i c o r g e l at i n , i t c a n n o t o x i d i s e i t s e l f . I t r e d u c e s s e n s i t i v i t y , h e n c e t h e l o n g e r e x p o s u r e t i m e s . I t i n c r e a s e s t h e c o n t r a s t b y c u t t i n g o f f h i g h - l i g h t s i n t h e t o n a l s c al e . The presence of the strong oxidising agent chromium (VI) will ten d to reverse the photochemical formation of silver metal, re-oxidising it to Ag+, it reduces sensitivity and increases contrast.” Mike Ware 28/11/07.

T he Sa l t p ri n t M a n u a l | T he Sa l t a n d Sil ve r Fo r m u la s 1 6

POTASSIUM DICHROMATE 5% SOLUTION

1 0 0 ml 5 g m

D is ti lle d Wa t e r Po ta ssi u m d ic h r o ma te M et h o d: 1 . Hea t wa te r to 2 0 °C . 2 . P u t on g lo ves , e ye p r ot ec t ion a n d d us t ma sk . 3 . D iss ol ve 5 g m o f po ta ssi u m di c h r o m a te in t he di s ti lle d

wa t er .

4 . St o re in a s m a ll s t o p pe re d b r o wn bo t t l e .

V a r yi n g t h e a m o un t of p o ta s si u m d i c h ro m a t e a ll o ws s o me con t r ol . T h e ex t re me u sa ge , i .e . 1 0 % po ta ssi u m d i c h ro ma te wi l l ca us e los s of i n fo r ma t ion in t he s ha do ws b ef o re t h e r e is de ta il in t he hi g hl i gh t s. A m m on i u m c hl o ri d e wi t h p o ta s s iu m di c h r o ma te is 8 % to 1 0 % co ole r in co lo u r t ha n so di u m c h l o ri de wi t h p o ta ss i u m di c h r o ma te .

SODIUM OR AMMONIUM CHLORIDE + POTASSIUM DICHROMATE

2 5 0 ml 5 g m

D is ti lle d wa te r Sodium chloride or a mmonium c hloride M et h o d: 1 . Hea t d is t ill e d wa t e r to 2 0° C . 2 . A dd t he sa l t t o t he di s til le d wa te r . I t w ill di ss ol ve ea s il y . 3 . Ta ke 3 0 m l o f sa l t s ol u ti on . 4 . A dd 2 d ro ps o f t he 5 % po ta ssi u m d ic h r o ma te s ol u ti on .

B I N D E R S

Bin de r s a re s u bs t a n ces t ha t bi n d t oge t he r t wo o r m o re

ma te r ia l s o r c he m i c a ls in a m ix t u re . T h e m os t co m m on l y u sed

in sa l t p rin ti n g a r e ge la tin a r r o wr o o t a n d a l b u men . T h eses

bin de r s ho ld t h e c h lo ri de , di s pe rs in g t he si lve r c h lo ri d e w hi le

h ol din g i t to t he p a pe r .

T he Sa l t p ri n t M a n u a l | T he Sa l t a n d Sil ve r Fo r m u la s 1 7

N B: To a vo i d s po il in g yo u r n e ga ti ve , m a ke s u re t he re is n o

exce ss of t he b in d er le f t on t he ed g es o f t he pa p e r. Even

t h o ug h t he pa pe r is d r y t hi s ex ce ss o r l u m ps h ol d s t he

m ois t u r e a n d a b so r b a g rea t e r % of t he sil ve r n i t ra t e. W hen t he

n ega ti ve

is pla ce d on t he sen s i ti ze d pa pe r s u r fa ce a n d

exp ose d , t he h u m i di t y c rea te d b y U V la mp s o r s u n c re a te s

m ois t u r e a n d n o t o n ly s t a in s b u t t he sof t bin de r l u m ps ma y

st ic k t o y o u r n ega t i ve.

G E L A TI N B I N D E R

T he ge la tin e bin de r a ct s a s a si zin g a gen t a n d t he f ol lo wi n g oc c u rs :

o T he i m a ge a p pea r s sh a rp e r a s t he g ela tin s to ps t h e sil ve r c hl o ri de so l u ti on f ro m be in g a bs o r be d in t o t he pa pe r f ib r es . T he i ma ge si t s on t he p a pe r s u r fa c e.

o

I t m a k es t h e i ma g e c ol o u r a p pea r c oo le r a t a s m a l l pe r cen ta ge, b ut a s t he p e rc en ta ge in c rea s es t he i ma ge be co m es wa r me r .

o T he p rin t wi ll a p pe a r to ha ve a s li g h t sh een , d ep en d in g

on t h e a m o un t o f ge la t in a dd ed t o t h e s ol u ti on .

o As t he p e rc en ta ge o f gela t in is i n c r ea se d in t he sa lt

sol u t io n t he te m pe r a t u re of t he so l u ti o n n ee ds t o be a t lea s t 2 0° C be fo re c oa tin g . C ol d ge la tin s ol u ti on s wi l l beg in to se t a s y o u a re coa t in g , ma kin g a s m oo t h e ven fin i s h d if fi c ul t to a c hie ve .

SODIUM OR AMMONIUM CHLORIDE SOLUTION + GELATIN

5 0 ml 2 g m 2 0 0 ml 5 g m

D is ti lle d Wa t e r Gela t in D is ti lle d Wa t e r So di u m c hl o ri de or A m m on i u m C h lo r i de M et h o d: 1 . Mix 2 gm of gelatin with 50 ml of the distilled water at room

temperature, lea ve f o r 1 0 m in u tes .

2 . Hea t t he 2 0 0 ml o f d is ti lle d wa te r t o 4 0 ° C . 3 . A dd t he sa l t. 4 . St i r in t he ge la tin . 5 . T he so l u ti on is rea d y wh en co ole d to a b o u t 2 0 °C .

T he Sa l t p ri n t M a n u a l | T he Sa l t a n d Sil ve r Fo r m u la s 1 8

A bo u t Gel ati n : „ Bl o o m fa c to r s ‟ mea s u re ho w r ig id t he g ela t in sol u t ion is wh en i t se ts . A la b g ra de p u r c ha se d f r o m a c he m ica l s u p pli e r w ill ha ve a b lo o m n u m be r o f a b o u t 1 2 5, a su pe r m a r ke t c oo k in g gela t in (a ls o ca lle d ge la tin e ) i s les s t ha n 1 0 0 . T he hi g he r t he bl oo m n u m b er t he f ir m e r t h e ge l fo r a n y giv en c on cen t ra ti on o f ge la tin .

2

Foo d g ela ti n a va i la b le f ro m s up e r ma r ke ts co m es in gra n ula r o r s h ee t f o r m . I t n o r ma l l y h a s t he p res e rva t i ve 2 2 0 s u lp h u r di ox id e ( CO ) . As s oon a s t he s il ve r n i t ra te sol u t ion is a p p lie d to a sa l t so l u ti on us in g t his t y pe o f gela t in a s a b in d e r i t s ta r ts to oxi d ise t he s il ve r b ef o re exp os u re s h o wi n g a ye ll o win g o r c h e mi c a l „ f og gin g ‟ e ffe c t . T his i mp a i rs t he hi g hl ig h t s a li t tl e. 18

A R R O W R O O T B I N D E R

A r ro wr o o t s ta r c h a c ts a s a s iz in g a n d :

o Cr ea tes a d ee p wa r m ton e

o En ha n c es d e ta i l in t he s ha d o w r eg ion

ARROWROOT FORMULA19

7 5 0 ml 2 0 g m 2 5 0 ml 1 4 g m 2 3 g m 7 g m

D is ti lle d wa te r A r ro wr o o t s ta r c h D is ti lle d wa te r A m m on i u m c hl o ri de So di u m ca r bon a t e Ci t ri c a c i d M et h o d: 1 . M ix t h e a r r o wr o o t s ta r c h wi t h a bo u t 2 0 ml o f t h e di s ti lle d

wa t er ma k in g a s m o ot h c rea m y s u sp en s ion . 2 . B rin g t o t he b oi l t h e ba la n ce o f d is t ill e d wa te r . 3 . Gra d ua ll y a d d t he s ta r c h wh i le s ti r r in g . 4 . Con tin u e t o b oi l un t il t he li q u i d is t ra n s lu ce n t . 5 . Wi t h t he se con d a m o un t o f di s ti lle d w a te r d iss ol ve in t he a m m on i u m c hl o ri d e , so di u m ca r bon a te a n d ci t r ic a ci d . Wh il e a d din g t h e c i t ri c a ci d t his s ol u t io n wi ll e ffe r ve sc e .

18 “ S u l p h u r d i o x i d e i s a r e d u c t an t , a p a r t f r o m t h e „ f o g g i n g ‟ t h e r e i s n o l o n g t e r m e f f e c t .” M i k e W a r e 2 0 0 7 . A l a n E l l i o t t s t at e s t h at s o m e S O 2 r e m a i n s b o u n d t o t h e g e l at i n .

19 W al l , E . J . a n d J o r d an , F . I . ( 1 9 7 5 ) P h o t o g r a ph i c F a c t s a n d F o r m u l as , A m e r i c an P h o t o g r ap h i c B o o k P u b l i s h i n g C o . , I n c . , N e w Y o r k U S A . p 2 5 8

T he Sa l t p ri n t M a n u a l | T he Sa l t a n d Sil ve r Fo r m u la s 1 9

6 . A dd t he s ol u t ion t o t he a r r o wr o o t a n d b oi l fo r 5 mo r e

m in u tes . T he s m el l of a m m on ia wi l l be q ui te st r on g .

7 . St r a in t h ro u g h c he e se cl o t h wh i le s t ill wa r m , l ea ve t o c oo l. 8 . Re m ove a n y s k in t ha t h a s fo r m ed bef o re a p pl y in g t o t h e

pa pe r .

Coa tin g pa pe r wi t h a r r o wr o o t is m o re c ha l len gin g t ha n o t he r bin de r s. T he a bo ve fo r m u la is s ui ta bl e fo r c oa tin g wi t h a r od o r b r us h . If t h e c oa tin g o f t he so l u ti on is t oo t hi c k, t he sen si t iv i t y of t h e si lve r n i t ra te s o lu t ion de c rea s es . T his c rea te s a p in k l ig h t b r o wn c ol o u r wi t h pl en ty o f de ta il b u t n o den s i t y in t he s ha d o w r eg ion s.

N ot e : S od i u m c i t ra te is n e ce ssa r y in t he s ol u ti on a s s ta r c h a lon e i s n o t a n a c t ive o r ga n i c s u bs ta n ce 20. Ci t ri c a ci d in n ot n ece ssa r y in t h e si l ve r n i t ra te , i t wi ll i n c rea s e sen si t iv it y b u t wi l l m a k e t h e pa pe r mo r e d iff i c ul t to to n e. 21

A L B U M E N B I N D E R

Al b u men is a n „a c t ive ‟ o rga n ic s u bs ta n ce ; i t in c rea s e s t he re d u ct io n of si lve r c h l or i de a n d s ilv e r a l b u min a t e. An a l b u m en p rin t is a sa l t p ri n t wi t h t he a l b u men bin de r . T h is bin de r will a d he r e t h e si l ve r i ma ge on t h e pa pe r s u rfa ce . Ex p er i men ts on a l b u m en wi t h o u t sa l t were ca r rie d o u t in 1 8 3 9 b y Ta lb o t a n d in 1 8 4 1 b y R ob e r t H un t . 22 T he i m a ge wa s c r ea t ed f r o m s il ve r n i t ra te fo r m in g s ilv e r a lb u m in a te s wh i c h re d u ce to m e ta l li c sil ve r on e xp os u r e t o lig h t . 23

Fre n c h p h o t og ra p he r B la n q ua r t -E v ra r d re fin e d t he p r oc ess b y a d din g t he c h l or i de a n d a n n o un c e d hi s s u c ces s in 1 8 5 0 . T he Al b u men p rin t in c o r po ra t in g c hl o ri de be ca me t he pr o m in en t p rin t in g pr o ces s o f t he mi d 1 9 t h cen t u r y a n d re ma in e d th e p rin ci pa l p r in tin g m et h o d un t il 1 8 9 5 . 24

20 R e i l l y , J . M . ( 1 9 8 0 ) T h e A l bu m e n & S a lt e d P a pe r B o o k : T h e H i s t o r y an d pr a c t i c e o f ph o t o g r ap h i c pr i n t i n g , 1 8 4 0 - 1 8 9 5 . , L i g h t I m p r e s s i o n s C o r p o r at i o n . , R o c h e s t e r , U S A . p 2 2

21 C r a w f o r d , W . ( 1 9 7 9 ) K e e pe r s o f t h e L i g h t , M o r g a n & M o r g an , I n c . , N e w Y o r k , U S A . p 1 5 3

22 H u n t , R . ( 1 9 7 3 ) A M an u a l o f P h o t o g r ap h y , A r n o P r e s s I n c . U S A . p 2 8 6

23 R e i l l y , J . M . ( 1 9 8 0 ) T h e A l bu m e n & S a lt e d P a pe r B o o k : T h e H i s t o r y an d pr a c t i c e o f ph o t o g r ap h i c pr i n t i n g , 1 8 4 0 - 1 8 9 5 . , L i g h t I m p r e s s i o n s C o r p o r a t i o n . , R o c h e s t e r , U S A . p ,2 8

24 I b i d . p 2 8

T he Sa l t p ri n t M a n u a l | T he Sa l t a n d Sil ve r Fo r m u la s 2 0

ALBUMEN FORMULA

250 ml ( approx 8

1 0 ml 4 g m 0 . 5 m l

Al b u men (e gg wh i t e ) to 10 eggs) D is ti lle d wa te r A m m on i u m c hl o ri de Gla cia l a ce t i c a c id M et h o d: 1 . Egg wh i t es m us t be in d iv i d ua l ly a n d ca r ef ul l y se pa ra te d .

T his iso la te s p ro b le ms wi t h o u t s p oi lin g pr ev io u sl y sepa r a t e d e gg s .

2 . Re m ove a l l co n t a mi n a t ion o f yo l k, s t r i n gy ti ss ue , bl o od o r

sh el l f ro m t he e gg wh i t es .

3 . D iss ol ve a m m on i u m c h lo ri d e in t he di s ti ll ed wa te r a n d a d d

gla cia l a c et i c a c id . 4 . A dd to e gg wh i t es . 5 . Bea t t hi s so l u ti on u n ti l a l l t h e so l u ti on is c on v e r te d t o

fr o t h .

6 . L et t he s ol u t ion s i t fo r 2 4 h o u rs i n t he re f ri ge ra to r . 7 . B rin g t o ro o m t e m p era t u r e . 8 . St r a in t ho u g h m u sl i n o r c hee se cl o t h t o re m ov e fo a m . 9 . Cov e r a n d re f ri ge ra t e f o r 1 wee k to f e r m en t .

Bea t in g t he eg g wh i te b rea ks do wn t h e a lb u m en in t o a un if o r m c on s is ten c y . T he sa l t a n d t he a ci d a s sis t wi t h fe r men t in g t he a l b u men s ol u t io n . T h e e a se of coa t in g in c re a ses a s t h e a l b u men a ges .

t h e

T he s il ve r n i t ra t e c oa tin g „ se ts ‟ o r c oa gu la te s t h e f i rs t coa t in g of a l b u m en . A se con d coa t in g o f a l b u men wi l l in c re a se t he s u r fa ce gl oss gi vin g a n ex t ra b ri ll ia n ce . U n f o rt u n a tel y t hi s sec on d c oa tin g will s of t en fi r st coa t of a l b u m en . Ha rd en in g is t h e re fo re n e ces sa r y be f o re a p pl y in g a se c on d coa t a n d c a n be a c h iev ed b y a n y of t he fol lo win g:

o St o ri n g t he fi r s t c oa t f o r a t lea s t f iv e m on t hs f o r i t t o

slo wl y „ c u re ‟ . 25

o Pla c in g in a ba t h of iso p r op y l a l co h ol 7 0 % fo r 1 5 sec on ds . T hi s c on s i st en tl y is t he m os t su c ces sf u l me t h o d wh en a pp l yi n g a s ec on d c oa tin g .

25 I b i d . p 3 9

T he Sa l t p ri n t M a n u a l | T he Sa l t a n d Sil ve r Fo r m u la s 2 1

o St ea min g t he s u rfa c e of t he fi r s t c oa tin g fo r 1

m in u te .

i r on se t a t

o Pla c in g a pie ce o f pa pe r ov e r t he s u rf a ce of t he d r y te m p e ra t u re a lb u m en a n d u sin g a n be t we en si l k a n d c ot t on , t h en mo ve t he ir on e ven l y ove r t he pa pe r . 26

M a n y tex t s a d vi se t ha t 2 % a m mon i u m c hl o ri d e s ho u l d be a d de d to t he ba t h of is op r o p yl a l co h ol a s t he ba t h lea c h es t he c hl o ri de f r o m t h e f ir s t c oa tin g. T es ts ha ve p r ov ed t hi s is n ot n ece ssa r y .

If t h e coa t in g is un sa t is fa c t o r y wh en d r y i t ca n b e p la ce i n a t ra y of co ol wa te r . The a lb u m en wi ll sof ten a n d even t u a ll y wa s h off a n d on ce d r y , t he p a p e r ca n b e re coa t ed . I h a ve fo un d t his us ef u l when e xp en si ve ha n d ma de pa p e rs ha v e been us ed .

A D V A N T A G E S O F A L B U M E N P R I N T S :

o T he i ma ge si t s on t he s u r fa ce o f t he pa pe r g iv in g t he a p pea ra n ce o f a g re a te r den s i t y ra n ge t h r o ug h t he re f ra c t io n of t he l ig h t .

o An a l b u men p rin t h a s a s li g h t s heen to glo ss y f in is h ed su r fa ce gi vi n g b r il li a n ce , a b sen t in sa l t ed pa p e r p r in ts .

U sin g a m m on i u m c h lo ri de in t h e a l b u me n s ol u t ion res u l ts i n t he co lo u r bein g 8 % to 1 0 % c oo le r t ha n us in g s o di u m c hl o ri de .

B y a d din g 2 d ro ps of p o ta s si u m di c h r o ma te 5% s ol u ti on i n 3 0 m l of t he a l b u m en s ol u ti on wi ll :

In c rea s e t h e c on t ra s t o f y o u r p r in t.

o

In c rea s e ex po s u re t i me .

o

S I L V E R N I TR A T E S E N S I TI S E R

S I L V E R N I TR A TE I S P O I S O N O U S I T IS A N O X ID IZ I NG AGE N T , CA N CA USE SE R IO U S PE R MA NE N T D AM AGE TO E YE S . WEAR GLOVES AND EYE PROTECTION.

26 J am e s , C . ( 2 0 0 2 ) T h e B o o k o f A l t e r n at i v e P h o t o g r a p h i c P r o c e s s e s , D e l m a r , N e w Y o r k . p 2 6 7

T he Sa l t p ri n t M a n u a l | T he Sa l t a n d Sil ve r Fo r m u la s 2 2

T he si lv e r n i t ra te sen si t is in g s ol u t io n m us t be ma de u sin g di s til le d o r de -i o n iz ed wa te r . Si lv e r n i t ra te rea c t s wi t h c hl o ri de a n d a n y ha r d wa te r ion s s u c h a s ca r b on a tes t ha t ma y exis t in ta p wa te r su p pl ies . T h e re s ul t o f c on ta min a t ion is a cl o u dy wh i t e p re ci pi ta t e of s i lve r c h lo r id e a n d s i lve r ca r bon a t e. T hi s de p ri ves t h e s il ve r n it ra t e o f i t s s t ren gt h , ma k in g sen si t isin g t he pa pe r le ss ef fe c t ive . 27

SILVER NITRATE SENSITISING FORMULA

5 0 ml 6 g m

D is ti lle d o r de - min e ra li ze d wa te r Sil ve r n i t ra t e M e th o d: 1 . P u t on g lo ves a n d e ye p ro te c ti on . 2 . A dd t he s il ve r n i t ra te to t he di s til le d w a te r . 3 . St o re in a b ro wn gla ss b o t tle .

Sil ve r n i t r a t e is n ot sen s i ti ve to l ig h t un l ess t he re is a n oxi da n t p resen t . M ixin g s ma l l a mo un ts of si lv e r n i t ra te sol u t ion re d u ces t h e ri s k of con ta m in a t ion t h ro u g h u sa g e .

If us in g t he gla ss r od me t h o d , t he a b o ve so l u ti on wi l l c oa t 2 0 to 2 5 s hee t s of pa pe r f o r 8x 1 0 in c h p rin t s . M o r e so l u ti on is us ed f o r t h e b r us h me t h o d , de pen din g on t he b r us h ty p e a n d si ze.

Inc rea se Si l ve r Ni t r ate Pe rc e n tag e : S m a ll in c rea se s in t he pe r cen ta ge o f sil ve r n i t ra te in t h e so l u t ion ca n be ben efi c ia l in p rin t in g l o w c on t ra st n e ga ti ves . A s t h e pe rc en ta g e in c r ea s es b ron z in g a f fe c ts t h e s ha d o w r eg ion s a n d y el lo wi n g in t he hi g hl ig h t s wi l l b egi n to s p oi l t he p rin t ‟ s t on a l ra n g e .

27 R e i l l y , J . M . ( 1 9 8 0 ) T h e A l bu m e n & S a lt e d P a p e r B o o k : T h e H i s t o r y a n d p r a c t i c e o f

ph o t o g r ap h i c pr i n t i n g , 1 8 4 0 - 1 8 9 5 . , L i g h t I m p r e s s i o n s C o r p o r a t i o n . , R o c h e s t e r , U S A .

T he Sa l t p ri n t M a n u a l | T he Sa l t a n d Sil ve r Fo r m u la s 2 3

T H E E F F E C T O F I N C R E A S I N G T H E S I L V E R N I T R A T E :

o 1 5 % in c rea s es t he con t ra s t . T he co lo u r i s c oo le r a n d sh o ws so m e l oss of de ta il in t h e s ha do ws . T he hi g hl ig h t de ta il is m o re a pp a r en t . T he p rin t is s ti ll a c ce p ta b le.

o 2 0 % c re a t es f u r t h e r i n c rea se in t he con t ra st a n d a fu r t h e r lo ss o f de t a il in t he s ha d o ws . T he re is so m e b ron z in g a n d m o re de ta il in t he hi g hl ig h ts .

o 3 0 % in c rea se s t h e c on t ra s t , a l lo win g l i t tl e de ta i l in t he sha d o ws . B r on zin g be co m es o bv io u s a n d t h e re is le ss de ta il in t h e hi g hl ig h ts . T he h ig h li g h ts ma y be c o me ye ll o w.

De c r ea se Si l ve r Ni t ra te Pe rc e n t ag e : A sm a ll r ed u c t ion in t he pe r cen ta ge of si lv e r n i t ra te in t h e s o lu t ion ma y s ho w s o me ben e fi t s in p rin t in g h ig h con t ra s t n e ga t ive s . As t h e p e rc en t a ge be co m es s ma ll er t h i s ma y res u l t in wea k in e ff ec t ive p rin t s .

T H E E F F E C T O F D E C R E A S I N G S I L V E R N I T R A T E :

o 1 0 % de c re a ses t he con t ra s t a n d t he p rin t a pp ea rs wa r m e r in c ol o u r . T he p rin t ma y be s t ill sa t isfa c t o ry .

o 5 % t he p r in t beg in s to lo se h ig h li g h t de ta il b u t ga in s sha d o w d e ta i l a n d i n c rea s es t he wa r m t h o f t h e c ol o u r.

o 1 % s h o ws li t t le de ta i l in t he h ig h li g h ts a n d t he m i d to n es de c rea se in c on t ra s t . T h e s ha do w de ta il is wea k . Sp o ts de sc r i be d a s „ mea sle s ‟ m a y a p pea r a f te r s o me ti m e.

sen si ti vi t y

lig h t

T he li g h t sen s i ti ve su bs ta n ce in sa l t a n d a l b u men p a p er i s sil ve r c h lo r i de . Si l ve r c h lo r id e is in s ol u bl e in wa t e r . S o di u m c hl o ri de so l u ti on is c oa te d on t he pa pe r fo ll o we d b y t h e s i lve r n it r a t e so l u ti on t h us c rea ti n g si lv e r ch lo r i de a n d so d iu m n it r a t e. So di u m n i t ra te i s so l u ble a n d is wa s he d a wa y d u ri n g t he p r oc ess in g . I f t he c h lo r id e a n d t he sil ve r n i t ra te a r e e q ua l o r is eq u iv a len t , si m ila r c h e m ica l re d u c ed . Ex ce ss s il ve r n it r a t e a l lo ws m o re d ra ma t ica ll y me ta ll i c sil ve r to b e fo r me d in t he p r i n t , t h u s in c r ea s in g t he den s i t y.

T he c i t ri c a ci d a d de d to t he s il ve r n it r a t e so l u ti on c r ea t es sil ve r c i t ra te , in c re a sin g s pe ed a n d wa r m in g t he c ol o u r ton es. 28

28 R e i l l y , J . M . ( 1 9 8 0 ) T h e A l bu m e n & S a l t e d P a p e r B o o k : T h e H i s t o r y a n d pr a c t i c e o f ph o t o g r ap h i c pr i n t i n g , 1 8 4 0 - 1 8 9 5 . , L i g h t I m p r e s s i o n s C o r p o r a t i o n . , R o c h e s t e r , U S A . p 4

T he Sa l t p ri n t M a n u a l | T he Sa l t a n d Sil ve r Fo r m u la s 2 4

SILVER NITRATE FORMULA WITH CITRIC ACID

5 0 ml 6 g m 0 . 7 5 g m

D is ti lle d o r de - min e ra li ze d wa te r Sil ve r n i t ra t e Ci t ri c A c id M et h o d: 1 . P u t on g lo ves a n d e ye p ro te c ti on . 2 . A dd t he s il ve r n i t ra te to t he di s til le d w a te r . 3 . A dd t he ci t r ic a ci d . 4 . St o re in a b ro wn gla ss b o t tle . M ixin g s m a l l a m o u n ts o f s il ve r n i t ra t e s ol u ti on r ed u ce s t he ri s k of con ta m in a t i on t h r o ug h usa ge . A h i g h p e r c e n t a g e o f c i t r i c a c i d c a n c a u s e b r o n z i n g a s i t i n c r e a s e s

t h e s p e e d t h e s i l v e r c i t r a t e a n d s i l v e r c h l o r i d e c o n v e r s i o n t o

m e t a l l i c s i l v e r .

T he Sa l t p ri n t M a n u a l | T he Sa l t a n d Sil ve r Fo r m u la s 2 5

CHAPTER 5

5. T H E P AP E R

S a l t pr i n t i ng br i ng s yo u i n to uc h w i t h t he a n c i en t c r a f t o f p a p er m a k i ng . A b as i c un d ers t a n d i n g o f t he s tr u c t u re a n d te x t u res o f p a p ers w il l p ro vi d e an o t h e r to o l to co n t ro ll i ng t he co lo ur a n d t he f i n a l lo o k o f yo u r pr i n t . T he re a re m a n y p a p ers t h a t w i l l no t w o rk w it h t h is pro c es s . T he re fo re y o u a re l i m i te d to us i ng q u a li t y 1 0 0 % r a g co t to n w a te r co lo ur p a pe rs . T h is c h a p te r e x p l ai ns w h y a n d o f fe rs s o m e s ugg es tio n o n v a r io us p a p ers to tes t . T he Bo o k o f F i n e P a pe rs b y S i lv i e T ur ne r is a b ri l l i a n t bo o k o n t h e h is to ry o f p a p er as w el l as a w o r l d w ide gu i d e o n f i ne p a pe rs a n d p a p er m i l ls .

1 0 0 % c o tt on p a p e r is t he p u re s t f o r m o f ce ll u lo se of f er in g hi g h s t ren g t h a n d t he l on g es t li fe o f a ll pa pe r s. 29 Co t ton is a sta b le ba s e fo r t h e si lv e r n i tr a te so lu t ion t he re fo r e m o re p re di c ta bl e in i ts re sp on s e t h ro u g h t he p r oc ess . Si zin g is a d de d to p r ev e n t s ol u ti on s f r o m s oa ki n g to o dee p ly in t o t he pa pe r t h us ma kin g t he c oa ti n g mo r e un if o r m . T he f ib r e s in pa pe r a r e ma de u p of s ho r t e r co t t on lin te rs o r c o t ton „ r a gs ‟. Ra gs f i b res a re lon ge r a n d s t ron ge r b u t les s co m m on l y u s ed . 30 U n de r st a n d in g t h e c ha ra c te ri s ti cs of pa pe rs , t he i r l ife a n d be ha vi o u r is o f g rea t va l ue wh en c ho os i n g pa pe rs . 31

P AP E R M A N U F A C TU R I N G

t he ma ke r ,

Fa b r ia n o in t r o d uc ed wa te r ma r k s in 1 2 7 2 . A c tin g a s re c ogn i ti on of t h ey p r o mo t e a n a ss u m p ti on o f q ua li t y. Wa t e r ma r ks a re n o r ma ll y cl ose t o t h e edg e o f t h e pa pe r a n d “ rea d r ig h t ” f r o m t h e to p s i de.

Pa pe r m a kin g ca n b e di vi de d in to t he t h re e f ol lo win g gr o u ps ; ha n d ma de , mo u l d m a de a n d ma c h in e ma de .

29 T u r n e r , S . ( 1 9 9 8 ) T h e B o o k o f F i n e P a pe r s , T h am e s a n d H u d s o n I n c , N e w Y o r k . p 1 6 2

30 I b i d . p 2 1

31 I b i d . p 1 9

T he Sa l t p ri n t M a n u a l | 2 6

T Y P E

A D V A N TA G E S

D I S A D V A N T AG E S

E x p e n s i v e , u n k n o w n p u r i t y a n d i r r e g u l a r s i z e s .

H A N D- M A D E

H a n d c r a f t e d c o t t o n o r l i n e n i n d i v i d u a l s h e e t s , l i t t l e g r a i n s o t h e r e f o r e s t r o n g e r .

C Y L I N D E R M O U L D M A D E

Q u a l i t y i s c o n s i s t e n t , l e s s e x p e n s i v e t h a n h a n d m a d e , w i d e v a r i e t y a n d e a s i l y a v a i l a b l e . M o s t w a t e r c o l o u r r a g p a p e r s a r e m a d e o n a m o u l d i n t h e f o r m o f a c y l i n d e r

M A C H I N E - M A D E C h e a p a n d r e a d i l y

a v a i l a b l e .

O wi n g t o t h e w i d e v a r i e t y i t r e q u i r e s r e s e a r c h t o u n d e r s t a n d t h e v a r i o u s t y p e s s u i t a b l e f o r s a l t p r i n t i n g . G r a i n i s l a i d i n o n e d i r e c t i o n t h e r e f o r e n o t a s s t r o n g a s h a n d m a d e p a p e r s Av o i d f o r i m a g e m a k i n g . I t i s a m a j o r p r o b l e m f o r l o n g e v i t y a s i t i s u s u a l l y f r o m wo o d p u l p , l i g n i n b l e a c h e s a n d o t h e r a d d i t i v e s t h a t c o n t r i b u t e t o a c h e m i c a l b r e a k d o wn i n t h e p a p e r .

A D D I TI V E S T O P A P E R

( A K D )

1 . S i zin g . Si zin g i s a d de d to in c rea s e su r fa ce s t r en g t h a n d re sis t s t he pen e t ra ti on o f so l u ti on s i n t o t he fi b res of t he pa pe r . Ge la tin a n d s ta r c h a re t he m os t c o m mon t y pe s of si z in g su i ta ble fo r sa l t p rin t in g . Al k yl - ke t en e - di m e r i s a syn t he t i c a r c h iva l i n te rn a l si zi n g a gen t whi c h a l lo ws t h e p a pe r to re m a in n e u t ra l p H. A q ua p el i s on e of t he t ra de n a me s fo r t hi s hy d r op h o bi c o r wa te r re pe llen t si zin g . Ge la tin e si zin g c rea te s a c oo le r to n e in t he p a p e r. 32 A wa r m e r c ol o u re d sa l t p rin t i s fo r m e d u sin g s ta r c h s iz in g .

Wa y s of s i zin g:

o S u rfa ce si z in g a ls o ca l le d t u b si z in g . T he d ry f in i s he d s h e et is i m m e rs ed in a b a t h of h o t gela t in fo r m in g a s kin o ve r t he pa pe r s u r fa ce a n d ha r den e d . T his is a pe r fe c t s u r fa ce f o r sa l t p r in tin g.

32 I b i d . p 1 3 3

T he Sa l t p ri n t M a n u a l | T he Pa p er 2 7

o In te rn a l si z in g is k n o wn a s b ea te r o r ma c hi n e . T he si z in g is a d de d t o t he p r o ces s be fo re t he f o r ma t i on of t he s h ee ts . 33

2 . Fil le rs a n d loa d in gs . M in e ra l pi g me n ts b in d t he f i b r es to ge t he r , f il lin g be t we en t h e ga ps c r ea t in g den s e r s hee ts . 34 T hese in cl u de c a l c iu m ca r bon a te (a c i d b uf fe r ), C hi n a c la y ( ka o lin ) , t i ta n i u m d iox id e a n d o p ti ca l b ri g h ten e r s. Av oi d t h ese a s t h e y rea c t wi t h t he si lve r n i t ra te be fo re ex pos u r e, c re a tin g c he m ica l f ogg in g .

3 . Wa t e rlea f . A t h e ref o re ve r y te r m fo r n o s i zin g a n d a bs o r ben t. I t is p r ob le ma t ic fo r sa l t pr in tin g c re a t in g fla t p rin t s a n d u n ev en co lo u r d ue t o t he hi g h a n d in c on si s ten t a bs o r pt io n ra t es o f t he s ol u t ion s.

S U R F A C E F I N I S H I N G

o Ro u g h. In h a n d ma de p a p e rs i t is a i r dr ie d c rea t in g a r o ug h te x t u re d s u r fa c e . In mo u l d ma de , a r o ug h fel t ma ke s t h e r o ug h s u rf a c e . 35

o NO T . C ol d p re sse d wh i c h m ea n s i t is n ot h o t p ress e d a n d is ha l f- wa y be t we en ro u g h a n d ho t p res s wi t h a tex t u re d fin i s h

o Ho t P r ess . A s m oo t h fi n is h us in g ho t r oll e rs o r p r ess ed

t h ro u g h c ol d po lis h ed me ta l r ol le rs .

W E I G H T A N D D E N S I T Y

T hi c kn es s o r we ig h t is r efe r r ed to a s gra m s pe r s q ua re me t r e (gs m ) . 2 8 0 gs m to 3 0 0 gs m is i dea l fo r sa l t p rin t in g b u t wi t h ca re l ig h te r we ig h t s c a n be us ed .

Den si t y re la tes t o h o w we ll t he pa pe r i s b on d ed . Den se pa pe r wi l l ex pa n d a n d c on t ra c t a s a wh o le a n d i ts ten de n c y t o c u r l is n o t a s g rea t . Pa pe r wil l c u rl mo r e wh en d en se r fi b re s a r e on t he to p s i de o f a she e t . T he s pe ed o f ex pa n s ion a n d con t ra c t ion a re t he r efo re a t di ffe r en t ra te s. 36

33 I b i d . p 2 4

34 I b i d . p 2 5

35 I b i d . p 2 8

36 I b i d . p 3 5

T he Sa l t p ri n t M a n u a l | T he Pa p er 2 8

C AR E O F P AP E R

o Ha n dle a s li t t le a s p oss ib le a n d b y t he e dge s , i dea ll y use

wh i t e c o t ton gl ove s. A v oi d c re a sin g t h e pa pe r .

o St o re f la t . Ro lle d pa pe r o ve r t i me c r ea t es a „ me m o r y‟

wh i c h ma k es t he pa pe r dif fi c u l t t o fla t t en o u t.

o Re m ove ma r ks ca r ef ul l y wi t h a so f t b r u s h o r e ra s e r. D is t u r b in g t h e s u r fa c e of t h e pa p e r ma ke s i t m o re a bs o r ben t a n d ma y re m ov e t he si z in g . St a in s m a y a p pea r in t he se a rea s .

P AP E R S F O R S A L T P R I N T I N G :

Pa pe rs s u it a b le f o r sa lt p rin t in g ha ve a rig h t a n d wr on g si de d ue to t he s u r fa ce s iz in g a n d t h e fin is h in g .

o T he pa pe r c h oi ce wi l l a ffe c t t h e co l o u r, c on t ra s t a n d

to n a l se pa ra t ion of yo u r i ma ge .

o Te m pe ra t u re a n d h u m id i t y wi ll a ffe c t t h e a bso r p t ion

ra te of t he so l u ti on s.

o To u c hin g t he pa pe r s u rfa ce in t he i ma ge a re a wi l l l ea v e oil s a n d sa l t f r o m yo u r s k in a n d ma y ca use s ta in i n g in t he f in a l p rin t .

o S mo o t h, ha r de r f in is he d s u r fa ce s i ze d pa pe r s gi ve a

sha r pe r , m or e b r il li a n t i m a ge .

o So l ut io n s sin k in t o po ro u s pa pe r . T h e im a ge a p pea rs

sof t er , c rea tin g a d ul l ma t t a p pe a r a n c e .

Tex t u re d p a p e rs a re m or e d iff i c ul t to coa t . T h is ca n be ove r c o me b y us in g a b r us h to a p pl y t h e so l u ti on . T he tex t u re re f ra c t s t h e li g h t , fl a t ten in g t he i m a ge a p pea ra n ce .

L is te d b el o w a re pa pe rs I ha v e u se d , in o r de r o f p r efe r en c e .

is e x ten s ive l y use d

I t

1 . BE RGG ER CO T 3 2 0 M O U L D M A DE 3 2 0 g sm HP ( F ren c h) . 1 0 0 % co t t on un - b uf fe re d a n d s u rfa ce s iz e d wi t h gela t in . M a de on a c yl in de r m o ul d , t hi s pa pe r wa s c re a te d sp ec if ic a ll y f o r pla t in u m p rin t in g . f o r o t h e r a lt e rn a ti ve p ho t og r a p hi c p ro ce sses a s it is a ci d- f ree , ha s n o op t ic a l b rig h t en e rs a n d is Ne u t ra l p H .

A dva n ta ges : I t ho l ds t he t on es be t te r t ha n a l l o t he r pa pe rs te st e d t o da t e. T h e sa l t p r in t is a co ol dee p b ro wn co lo u r a n d is c on s is ten t in it s pe rf o r ma n ce a n d q u a li t y.

T he Sa l t p ri n t M a n u a l | T he Pa p er 2 9

D isa dva n ta ges : T h is pa p e r is a l it t le m o re ex pe n si ve .

2 . TAL BO T HA N DM A DE 2 4 0 gs m 1 0 0% (F r e n c h ), 1 0 0 % lon g f i b re co t t on , ma t t fin is h a n d s u rf a c e s iz e d wi t h ge la tin . S hee ts a re p re sse d sev e ra l ti me s in b o t h wet a n d d r y s ta t e t o m in i m ise po r os i ty .

A dva n ta ges . I t h el d t he ton es in bo t h hi g h li g ht a n d s ha d o ws sh o wi n g 1 8 s te ps . Th e sa l t p rin t i s wa r m dee p re d b r o wn co lo u r a n d is con si s ten t in pe r fo r ma n ce a n d q ua li t y .

D isa dva n ta ges . T h e re a re s o me in t r in si c in con sis t en c ies i n t he pa pe r ; b u t t hi s is e xpe c te d wi t h ha n d ma de pa pe rs . T h is pa pe r is a li t t le m o re e xp e n siv e .

3 . ARC HE S PL AT I N E M O U L D M A DE ( F ren c h ) 3 1 0 g s m H P 1 0 0 % co t t on . It is un - b uf fe re d a n d s u rfa c e si ze d wi t h s ta r c h . Ac i d- f ree wi t h n o op t ic a l b ri g h ten e r s a n d is N e u t ra l p H. M a de a t t he A r c hes m il l in F ra n ce on a c yl in d e r mo u ld , t hi s pa pe r wa s c rea t ed spe c ifi ca ll y f o r pla tin u m p r in t in g. I t i s a lso ex te n si ve ly u sed f o r o t he r a l te rn a t ive p ho t og ra p h ic p ro ce sse s.

A dva n ta ge s : H ol ds t he ton es ex t re me l y wel l a n d i s c on si s t en t in i ts p e rf o r ma n ce q ua l i t y , a n d is u s ua ll y a va ila bl e .

i s m o re exp en si ve t ha n o t he r

D isa dva n ta ges : T h i s pa pe r pa pe rs .

4 . FA BR I A NO A RT I ST IC O M O U L D M A DE ( I ta l ia n ) 3 0 0gs m H P 1 0 0 % co t t on . I t is un - b uf fe re d a n d s u rf a c ed si ze d , a l so a va ila b l e in a r o ug h s u r fa c e whe r e be s t r es ul t a re a c hi ev ed b y b r us h in g t he c oa t in g on .

A dva n ta ges : T he s u rf a c e s i zin g h ol d s t he t on e s we ll . I t is in ex pen s iv e a n d rea di l y a va i la bl e .

D isa dva n ta ges : T he pa pe r is q u i te w a r m in co lo u r s o t he hi g hl ig h t s a re n o t a s c lea n a s t h e p rev i o us pa pe rs . O c ca s io n a l p ro b le ms f o un d wi t h q ua l i ty in c on s is te n ci es .

5 . BU XTO N HA N DM A DE PL A T I NO T YP E 2 4 0 gs m 1 0 0% c ot t on H P

un -b u f f er e d in te rn a ll y si ze d wi t h Al k y l - ke ten e - di m e r ( A K D )

a syn t he t i c a rc h iva l in t e rn a l s i zin g a ge n t , t his h y d ro p h o bi c

o r wa te r re pel len t s iz in g . P r o d uc ed in R us c o m be M i ll F ra n c e ,

it wa s de vel o pe d i n co lla b o ra ti on wi t h D r M i ke Wa re fo r

pla t in u m p r in tin g .

T he Sa l t p ri n t M a n u a l | T he Pa p er 3 0

A dva n ta ges : C ol o u r M id ton e s se pa r a te d we l l. T h is p a p er

w o rke d ex t re m e ly w el l fo r al b u m e n pr i n t i ng g i vi n g t h e f i nes t

res u l t o f a l l p a p e rs a n d s ur f a c es t es te d w it h t h is fo r m u l a .

D isa dva n ta ges : W he n a p p ly in g t he si l ve r n i t ra te so l u ti o n t o t he sa l t t he A K D c rea t ed a c h e mi ca l fog wh i c h re d u ce d t he hi g hl ig h t s a n d f la t ten ed t he s ha d o w reg ion s a li t t le. T his pa pe r n ee d to b e we ll se c u re d wh i le c oa tin g , d ue t o t he li g h te r we ig h t i t wi l l c u r l w hen m oi st u r e is a p p lie d .

O T H E R P A P E R S T R I E D :

o SAU N D ER S WA TE RF O R D

(En gl is h ) 3 0 0 gs m HP 1 0 0 % co t t on un - b uf fe re d , in te r n a ll y a n d s u rf a c e si ze d wi t h gela t in e . A ve ra g e p ri ce ra n ge ho ld s t on es we ll , ha s a ve r y wa r m to n a l r a n ge . L os es t he hi g hl ig h t s t o t he wa r m t on es of t he pa pe r. Al so a va i la bl e in 1 5 0g s m a lig h t l y tex t u re d s u r fa c e . wh i c h s ho w a m in o r fla t ten in g of t he i ma ge .

ca r bon a t e

c a l ci u m

pa pe r .

T h e

o R IS I NG S TO NE HE NG E M A CH I N E M A DE ( En gl is h ) 2 4 5 gs m NO T 1 0 0% c o t ton , b uf fe re d wi t h ca lc i u m ca r bon a t e. i s In ex p en si ve p ro b le ma ti c wi t h t he sen s i ti vi t y of si lve r n i t ra te . T h is pa pe r is a bs o r ben t , c rea ti n g a d u ll p rin t .

o AR CHE S AQ U A REL L E M O U L D M A D E (F r e n c h ) 3 0 0 gs m H P 1 0 0 % c ot t on un - b uf fe re d, in t e rn a l l y a n d s u rfa ce s iz ed wi t h ge la tin e . G iv es a r ea s on a ble t on a l ra n ge wi t h pl ea sa n t wa r m t on es. M o r e e x pe n si v e t ha n F a b r ia n o A r tis t i co .

o FA BR I A NO T IE PE L O M O U L D M A DE Wa t e r co lo u r ( I ta l ia n ) 2 9 0 g s m 1 0 0 % co t to n in te r n a l ly s i ze d . A wel l p r ic e d, ve r y so f t s u rfa ce d p a pe r wi t h a hi g h a bs o rp t ion ra te , un s u i ta ble fo r pla in sa l te d p ri n ts b u t i m p ro ve s wi t h a gela t in b in de r a n d e xt ra s iz in g .

o L A NAQ U AL L E M O U L D M A DE , 3 0 0gs m HP , 1 0 0 % c o t ton , un -b u ff er e d, i n t e rn a l & ex t e rn a l l y si z ed . We ll p ri ce d, b u t res u l ts ha ve be en d isa p po in tin g re su l tin g in b lo t c h y p rin t s d ue t o t he u n even a b so r p ti on , e ven wi t h bin de r s in t he s a l t s ol u ti on .

o CR A NE‟ S D I PL O M A PA RC HM E N T (U S A) ( re pla ce m en t f or Cra n es P la tin o t yp e) M A CH I NE M A D E 1 7 7g s m H P 1 0 0 % co t t on R osin & A l u m s iz ed .

T he Sa l t p ri n t M a n u a l | T he Pa p er 3 1

o CR A NE K I D F I NI S H (U SA ) gs m 1 4 0 1 0 0 % co t t on un - p res se d L ig h t we ig h t n ee ds ca re f ul ha n d lin g c oa ti n g a n d in p r oc ess in g ba t hs .

A D D I N G S I Z I N G T O P A P E R

M a n y pa pe rs a re s i ze d d u r in g ma n u fa c t u rin g a n d bin de r s a ct a s si zin g , h o we ve r t he re a r e s ti ll t he f oll o wi n g a dv a n ta ge s in p re - si zi n g o r res i zi n g t he pa pe r bef o re c oa ti n g .

1 . U sin g po r o us pa pe r s t ha t a re n o t p re - si ze d. 2 . A dd in g a n ex t ra f in i sh t o t he s u r fa ce . 3 . U sin g pa pe rs t ha t a r e hi g hl y tex t u r ed . 4 . T he d if fe ren t s iz in g t yp es a l lo w c on t r ol o f t h e c ol o u r. 5 . U sin g di ffe r en t t y pe s of s u r fa c es .

T he si z in g c a n be :

o Ge la t in . o Gela t in ha r de n e d wi t h g ly oxa l . o A r ro wr o o t .

GELATIN SIZING

1 0 0 ml 3 0 g m 9 0 0 ml

D is ti lle d Wa t e r Gela t in D is ti lle d Wa t e r M et h o d: 1 . A dd 1 0 0 ml of t he wa te r to t he gela t in . 2 . Al lo w t o b lo o m (s we ll ) fo r 2 0 min u t es a t ro o m te m pe ra t u re . 3 . A dd t he 9 0 0 m l of t h e wa te r . 4 . Hea t to 6 0° C. 5 . Po u r s ol u ti on in to a wa r m t ra y . Si t t h is t ra y in s id e a la rg e r t ra y fi ll ed wi t h h o t wa te r to ma in ta in a te m pe ra t u re of a t lea s t 2 0° C.

6 . A dd s h ee ts o f pa pe r on e a t a ti m e. 7 . S h uff le t h e s he e ts fo r a t lea s t 3 m i n u te s a n d u p to 5

m in u tes .

8 . Re m ove s hee ts on e a t a ti m e, a n d pl a ce on a fi r m fla t

su r fa ce .

9 . U sin g a g la ss ro d si m ila r in s i ze t o t he pa pe r , g en tl y sq ue ez e t h e ex ces s sol u t ion do wn a n d off t he e d ge o f t h e pa pe r .

1 0 . Ha n g to d r y.

If t he so l u ti on c oo ls b el o w 2 0° C, i t wi l l n o t coa t e ven l y . A sec on d c oa t of gela t in wi l l a ss is t wi t h r o ug h tex t u re d s u r fa ces .

T he Sa l t p ri n t M a n u a l | T he Pa p er 3 2

H AR D E N I N G TH E G E L A TI N S I Z I N G:

Ch e mi ca ls us ed f o r ha r den in g gel a tin a re gen e ra ll y d a n ge r o us . O n ly use t h e m i f yo u fin d t he u n ha rd en ed gela t in s i zin g is n o t a de q ua te . A vo i d fo r ma ld e h yd e!

If y o u d o no t ha ve ac c e s s to a f u m e c up b oa rd , we a r r u b be r g l o ve s, g a s m a sk a nd ey e pr o te c ti on .

T he Sa l t p ri n t M a n u a l | T he Pa p er 3 3

GLYOXAL HARDENING FORMULA

1 0 0 0 ml 5 0 ml

Wa t e r Gl yox a l 4 0% M et h o d: 1 . P u t on ma s k , gl o ves a n d ey e p r o te c ti on . 2 . A dd t he g l yox a l to t he wa t er . 3 . A dd t he s o di u m ca r bon a t e. 4 . Pla ce t he s h ee ts in ba t h . 5 . Ca r e f u ll y s h uf fl e t h e s h ee ts f o r 1 0 m in u te s . 6 . Re m ove a n d p la ce in a fr es h wa te r ba t h to re m ov e ex ces s

ha r den e r . 37

7 . W a s h fo r 2 0 m in u te s c ha n g in g wa t e r a b o u t e ve r y 5 min u te s . 8 . Ha n g to d r y in a wel l ven ti la te d ro o m .

T he a d di ti on of so di u m ca r b on a te c re a te s a n a l ka lin e b a t h t o a ssi st t he b in din g b et we en si zin g a n d h a r d e n e r a s t he h ig h p H ma x i m is es t he h a r den in g 38. T his wi ll c rea t e se ve r e c he m i cal fog gin g t h e ref o re i s o m i t te d f ro m t h e f o r m ula .

37 W ar e , M . ( 2 0 0 6 ) T h e C h r y s o t y pe M a n u a l , T h e C r o m w e l l P r e s s L t d , U K . p 4 7

38 W al l s , H . J . a n d A t t r i d g e , G . G . ( 1 9 7 7 ) B a s i c P h o t o S c i e n c e , h o w p h o t o g r a p h y w o r k s , F o c al P r e s s , L o n d o n . p 2 1 2 .

T he Sa l t p ri n t M a n u a l | T he Pa p er 3 4

CHAPTER 6

6. C O AT I NG TH E P AP E R

O ne o f t he o r ig i n a l m et ho ds us e d to co a t p a p er w as to fl o a t t h e s he e t o n t h e s u r f ac e o f a s o l u t io n i n a “ b a t h ” o r tr a y . A mo re co n tro l l e d m et ho d i s to us e a g l as s ro d a n d a s yr i ng e to a p p l y t he s o l u t io ns . T h e c o a t i ng is mo re ev e n a n d t h e r a t io be tw ee n t he s a l t a n d t h e s i l v er ni t r a te s o l u t io n i s mo r e co ns is t en t

Coa tin g t h e pa pe r is b r o ken in t o t he foll o wi n g t h ree b a si c me t h o ds .

1 . Fl o ati ng or s u bm e rg i ng i n a s ol u ti o n Ba t h . T h e pa pe r ca n b e c o m pl ete l y s u b me r ge d o r t he e dg es o f t he pa pe r ca n be t u rn e d up t o r es em b le a b oa t flo a t in g on t h e s u rf a ce o f t h e so l u ti on .

2 . Bru s hi ng On . U s in g b r u s hes wi t h m e ta l pa r ts wi l l rea c t wi t h t he s il ve r n i t ra te s ol u t ion . S pon ge b r us he s a n d B uc k le b r us hes wo r k wel l . A B uc k le b r us h i s ma de b y t wis t in g co t t on woo l in to a tes t t u be .

3 . Dr ag g i n g o r pu s hi ng t he s ol u ti o n . G la ss ro ds , a ls o kn o w a s p ud d le p u s he r s o r c h e mi ca l p u sh e rs , p us h t he sol u t ion ev en l y a c r oss t h e pa pe r , b y mea s u rin g t he sol u t ion o u t wi t h a sy r in ge t h is coa tin g s ys t e m i s ec on o m i c, fa s t a n d p re ci se.

A D V A N T A G E S

D I S A D V A N T A G E S

Often stated as an even way of coating the paper.

Floa t in g

B r us h in g

Relatively fast, easy method. Sponge brushes are cheap and easily obtained. Brushes for salt can be reused.

P us h in g

More solution is used therefore, longer drying time. The quantity of solution absorbed into the paper is inexact. Even coatings can be difficult. Brushes for the silver nitrate solution become contaminated when coating the salted paper and need careful washing, or to be replaced. The rod needs to match the negative size; a flat firm surface is required for coating. The glass rods are breakable.

Economic, precise, fast and easy method. Glass rods are reusable, easily washed leaving no chemical trace. Inexpensive.

T he Sa l t p ri n t M a n u a l | C oa ti n g t he Pa p er 3 5

P R E P AR I N G TH E P AP E R

Cu t o r tea r t he pa p er a bo u t 5 0 m m ( 2 i n c hes ) wi de r t ha n yo u r n e ga ti ve o r i ma ge si ze . T he ex t ra wi d t h m a kes ha n dl in g t h e pa pe r ea sie r t o a v oi d to u c hin g t he i m a ge a rea . M a ke s u re t he wa te r m a rk i s n o t i n t he i m a ge a r ea . Al lo w r o o m fo r t he st ep we dg e. M a r k o u t t h e i m a ge si ze a n d n o te in pen c il on t h e ed ge o r on t he re ve rs e of t he pa pe r ( o u ts id e t h e i ma ge a rea ) t h e fo ll o wi n g :

1 . T he so l u ti on y o u a r e us in g .

2 . T he a mo un t of s ol u t ion ( if us in g a s y ri n ge) .

t he pa pe r , da r ke r s ta in s

T he ro d s ho u ld si t a t lea s t 2 0 m m in f r o m t he o u t e r e dge s of t he pa p e r . I f t h e s ol u ti on m ig ra t e s ov e r t h e e dg es a n d a bso r bs in t o t he re ve rse si de o f t he p a p e r i t wo u l d c rea te a p ro bl e m fo r t h e n ex t co a t. Silv e r n i t ra te so l u ti on a b so r bs un e ven l y i den t if yin g wh e re sa l t t h ro u g h sol u t ion h a s a bs o rb ed in to t he pa pe r s re ve rs e . A pa pe r to we l un de r t h e pa p e r a ll o ws s up p len e ss on t he pa pe r s u rf a c e ma k in g i t ea sie r to coa t e ven ly .

Kee p in g t he pa pe r a n d t he so l u ti on a t r oo m t e m pe ra t u re m in i m ise s t he c u r li n g o r b u c k lin g o f t he pa p er a s t h e s ol u ti on is a pp li ed . St o p t he pa pe r m ov in g d u rin g a p p li ca ti on by ta p in g do wn t h e c o rn e rs to t he gla ss s u r fa c e o r pin to h ea v y ca r db oa r d. T he t a p e sh o ul d b e of t h e re m ova b le t y pe , n ot ma sk in g ta pe . U se a d u s t bl o we r to re m ove a n y pa r t ic les , h a i r o r d us t off t he s u r f a ce o f t h e pa pe r .

C O ATI N G L I G H T W E I G H T P AP E R S AN D F A B R I C:

L ig h t wei g h t pa pe r ma ke s i t di ff ic u l t t o coa t e ven l y d ue t o t he pa pe r b uc k lin g. T h e fo ll o win g me t h o d i s u se f ul a l so w hen coa t in g la r ge r p r in ts a n d fa b ri c. T h e foll o wi n g me t h od of st re t c h in g o ve r co m es t h ese p ro bl e ms .

1 . L ea ve p len t y o f s pa ce a r o un d t he i m a g e t o a l lo w f o r t he ta pin g d o wn of t he pa pe r . Pa pe r bo r de r s sh o ul d be a bo u t 7 5 m m la r ge r t ha n t he n e ga ti ve .

2 . Soa k t he pa p e r in wa r m wa te r fo r 5 min u te s.

3 . Re m ove f ro m t ra y a n d a l lo w t he wa t e r to d ri p ba c k in to

t he t ra y f or a f e w m o men ts .

4 . Pla ce on a g la ss s u rf a c e la r ge r t ha n t he pa pe r a n d bl o t

d r y wi t h c o t to n t o wels .

T he Sa l t p ri n t M a n u a l | C oa ti n g t he Pa p er 3 6

5 . Ta p e d o wn a ll s id e s wi t h g u m m ed ta p e, t hen da b ov e r

ca re f ull y a ga in wi t h c o t ton pa pe r to wel s.

is g on e

6 . Wh en mo s t o f t h e da m pn e ss fin i s h d r y in g wi t h a ha i r d r ye r.

7 . L ea ve t h e pa pe r o n t he g la ss fo r b o t h of t he s ol u ti on c oa t in gs. S to r e in a d a r k o r di m lig h t pla ce wh e n d ry in g t he s en si t i ze d pa pe r .

N B: F a b r i c s ho u l d b e 1 0 0 % c o t ton , wa s h a n d d r y be fo re u sin g to re m ove a n y si z in g e tc . I t is ea sie r t o su b m e rge t h e fa b ri c in t he sa lt s ol u t ion a n d t h en ta pe i t do wn . S il ve r n i t ra t e is a p pl ie d wh en d r ie d , b ut st il l t a p ed do wn , wi t h a s pon ge br us h .

S AL T C O ATI N G

T his ca n b e ca r r ie d o u t un de r n o r ma l l i gh t in g .

Ro d me t h od of a p pl ica t ion f o r a n 8 x 1 0 in c h p rin t :

1 . D ra w u p 2 m l o f so l u ti on in t o t h e s y rin ge .

2 . 2 0 m m in f r o m t he ma r ke d i ma ge a rea g en t l y di sp en se a l l t he s ol u t ion on to t he pa pe r in a l in e , st o pp in g 2 0 m m f ro m pa pe r e dge .

3 . Gen tl y p la c e t he r od in t his l in e of fl u i d, wi t h ca r ef u l si de wa r d mo ve men ts a l lo w t he f l ui d to ev en l y d is pe r s e a lon g t h e f ul l len gt h o f t h e r o d .

4 . L if t t h e r o d ov e r t h e sol u t ion s o t he r od s i ts b e t ween t he

pa pe r e dge a n d t he sol u t ion .

5 . P us h t h e s ol u t ion t o t he o t he r en d of t he p a p e r , a t l ea s t 2 0 m m be yon d t he i ma ge a rea . T he p us h s h o ul d b e a t a con s ta n t s mo o t h st ea d y r a t e wi t h ve r y li t t le p re ss u re . T h i s sh o ul d ta ke a bo u t t en s ec on ds .

6 . Ch ec k fo r un coa te d a r ea s , i m m e dia te l y d ra g t he s ol u t io n

ba c k ov e r t h ese a re a s t o a vo i d u n ev en coa t in g .

7 . Aga in li ft t he r o d o ve r t he s ol u t ion so t he ro d si ts be t we e n

t he pa pe r e dge a n d t he l on g po ol of s ol u ti on .

8 . Gen tl y p u s h t h e so l u ti on to t he o p p osi t e en d o f t h e pa pe r .

9 .

If t he pa pe r is e ve n ly co ve re d wa it f o r 3 0 se c on ds wh i l e t he s ol u t ion a bs o r b s i n t o t he p a p e r.

1 0 . T he re m us t be en o ug h s ol u ti on to c on tin ue p us h in g a t

lea s t 4 mo re t i mes s m oo t h l y a c r oss t he pa pe r .

1 1 . T he re s ho u ld be n o p u d d l es o f so l ut i on o r a rea s w i tho u t

co ve r ag e .

T he Sa l t p ri n t M a n u a l | C oa ti n g t he Pa p er 3 7

1 2 . An y ex ces s ca n b e re m ov ed gen t ly w it h a pa pe r t o we l , a vo id in g t he i ma ge a rea or h ol d t h e pa pe r b y a c o rn e r a n d a ll o w a n y e xc ess t o r un o ff .

1 3 . Ha n g o r la y t he pa p er so l u ti on si de u p to d r y . A ha i r d r ye r on t he wa r m se t tin g wil l s pee d u p t he p r oc ess . Kee p in g t he d r ye r 1 0 c m a wa y f r o m t h e pa pe r s u r fa c e.

Wh en us in g a h ig he r pe r cen ta ge o f g el a ti n in t he sa l t so l u ti on en s u re t ha t t h e pa pe r a n d t h e so l u ti o n a re hea te d to a t lea s t 2 0 ° C t o 2 2 °C . T hi s s t op s t he ge la t in se t tin g a n d „d r a g g in g ‟ un e ven l y d o wn t he pa pe r . In c rea sin g t h e q ua n ti t y of f l ui d a p pl ie d to t he pa pe r e a ses t h i s p r o ble m . Fo r exa m p le , a 8x 1 0 i ma ge n o r ma ll y re q u i res 2 m l o f sol u t ion , t he re fo re i n c rea s e t h is to 3 ml .

B r us h me t h o d of a p pl ic a t io n : P re pa re t he pa p e r t he sa m e wa y a s t h e sa l t c oa tin g.

1 . Po u r 2 0 ml o f sa l t so l u ti on in t o a di s h wi de en o u g h to

a c co m m o da te t he br us h wi d t h .

2 . Al lo w t h e b r us h to a bs o rb t he m oi s t u re .

3 . Re m ove e xc ess o ff t he b r us h .

4 . Pa in t on t h e so l u ti o n by r un n in g t he b r us h u p a n d d o wn t h e

pa pe r , ov e rla p pin g ea c h s t r o ke sl ig h t ly .

5 . En s u re t he re a re n o ga p s.

6 . T u rn t he pa pe r 4 5 ° a n d re pea t t he b r us h in g , re pea t t he

t u rn i n g a n d c oa tin g a f u r t he r 2 ti me s .

7 . T he re s h o ul d b e n o p u dd les o r a r ea s n o t c ov e re d.

8 . Ho ld t he pa pe r b y a c o rn e r a n d a l lo w a n y ex ces s t o r un of f .

9 . Ha n g to d r y h a n g o r pla ce t he p a p e r so l u ti on s id e u p .

1 0 . Yo u ca n u s e a ha i r d r ye r on t he wa r m se tt in g t o sp ee d up t he d r yin g , ke ep in g t he d r ye r a t lea s t 1 0 c m f r o m t h e pa pe r su r fa ce .

Al lo w t h e s ol u ti on to soa k in be fo re u sin g wa r m a i r t o d r y a s t hi s wil l gi ve a mo re con sis te n t e ven su r fa ce . Exc ess iv e hea t wh i le s t il l q u i te d a m p wi ll d r y t h e sa l t on t he s u r fa ce lea vin g sa l t c r ys ta l p a t c h es . T he sa l te d pa pe r wi l l ke e p in def in i te ly . M a ke s u re t he p a pe r i s c o m ple t el y d r y b ef or e a d d in g t he sen si t ise r .

T he Sa l t p ri n t M a n u a l | C oa ti n g t he Pa p er 3 8

A L B U M E N C O A TI N G

Al b u men is n o t a s ea sy to co a t a s pla in sa l t . B ub b les a n d lu m p s c re a t e da r k s po t s a n d ci r cl es . U n even s t rea k s wil l s h o w a s di ff e rin g den si ti es in t h e fin a l p r in t .

o

In c rea s e t he a m o u n t of s o l u ti on y o u a p pl y . T he exce ss so l u ti on a l l o w s c on t ro l o ve r t he s mo o t hn e ss of t he c oa tin g .

o A dd in g 0 . 5 % o f we t t in g a g en t to t h e a l b u men so l u ti on t he o re ti ca ll y re d u c es a i r b u b ble s on t he s u rfa ce of t he pa pe r a n d f o r ms s mo o t he r coa t i n gs . 39 I fo un d t he re wa s n o t a sign if ica n t d iff e re n ce wi t h t h e we t t in g a gen t .

o Re m ove a n y e xc ess a lb u m en a r o un d t he ed ges o f t h e p rin t ; t he e xc ess fo r ms h a r d l u m ps t ha t ma ke i t di ff ic u l t to m ove t he r od even l y a c r o ss t h e pa p e r wh e n a p pl y in g t he s ilv e r n i t ra te s ol u t io n .

S Y R I N G E : I f 2 m l is u sed on a n 8 x 1 0 sa lt p rin t , in c rea s e t hi s to 3 t o 3 . 5 ml of a lb u m en . M ove ro d sl o wl y a n d t he sm o o t hl y u p a n d d o wn t he pa pe r . W h en b u bb les a p pea r s to p c oa tin g a n d a l lo w t h e ex ces s t o r u n o ff t he pa pe r e dge b y h ol din g u p b y on e co rn e r .

B R U S H I N G . A ll o w p l en t y o f s ol u t ion s o yo u ca n sl o wl y a n d gen tl y b r us h t he so l u ti on on t o t he pa p er .

D R Y I N G . A bo u t 3 0° C wi ll c re a te a glo ss ie r fin is h f o r th e a lb u m en .

T he si lv e r n i t ra te c oa tin g se ts o r coa g u la t es t he f i rs t c oa ti n g so t he re i s n o n ee d to ha r den t h is un le s s a se c on d c oa t of a lb u m en is des i re d . H o we ve r a se con d coa t i n c r ea se s t he su r fa ce gl os s , t he re b y p r od u c in g a n ex t ra b ril lia n c e t o t h e a lb u m en p r in t. Ha r d en in g i s ess en tia l t o a v oi d s of ten in g t he fi rs t a l b u m en c oa t wh i le a p pl y in g t he s ec on d . T h e d r ie d a lb u m en is wa t e r so lu b le un ti l ha r de n e d wi t h :

o Ti me o Sil ve r n i t ra t e o Al co h ol

39 R e i l l y , J . M . ( 1 9 8 0 ) T h e A l bu m e n & S a lt e d P a p e r B o o k : T h e H i s t o r y an d pr a c t i c e o f ph o t o g r ap h i c pr i n t i n g , 1 8 4 0 - 1 8 9 5 . , L i g h t I m p r e s s i o n s C o r p o r at i o n . , R o c h e s t e r , U S A .

T he Sa l t p ri n t M a n u a l | C oa ti n g t he Pa p er 3 9

U n sen s i ti ze d a l b u m en wi l l s to re in d ef i n it el y in a n a i r t ig h t con ta in e r in co ol co n di t ion s wi t h rela t i vel y s ta bl e te m pe ra t u r e s a n d lo w r e la ti ve h u mi d it y .

S E N S I TI S I N G TH E P AP E R

Ea r lie r me t h o ds of sen si t is in g we re pe rf o r me d b y fl oa tin g t h e sa l te d pa pe r on t h e su r fa ce of a ba t h of si lve r n i t ra t e s ol u t i on . T his da ng e r ou s p ra c ti ce a n d wa s te f ul me t h o d a s i t c on s u me s la rge a mo u n t s of s i lve r n i t ra te . I s t r on gl y s ugg es t t h e re is n o phy si c al c on t ac t w i th si l v er ni tr a te . T he g la s s ro d a n d t he sy r in ge m e t ho d of coa t in g wi l l e va d e a ll co n t a c t wi t h t he sil ve r s ol u ti on .

A s y rin ge ( wi th o ut t he ne edl e ) ma k e s it ea s y t o c on t ro l t he a m o un t o f si lve r n i t ra te s ol u t ion a p pl ie d. E ven t h o ug h t he r e is n o p h ys ic a l c on ta c t wi t h t he s il ve r n i t r a te yo u s t il l m u s t we a r p ro t ec t ive gl ove s. D o n o t t o u c h t h e s y rin ge ti p on t he s a lt e d pa pe r . T hi s wi ll con ta m in a te t he res t of t he s il ve r n i t ra te when d ra wi n g mo r e so l u ti on in to t he s y r in ge fo r t he n ex t p rin t .

U se t he sa me q ua n ti t y of si lv e r n i t ra te so l u ti on a s t he sa l t sol u t ion . Fo r e xa m p le if 2 ml o f sa l t s o lu t ion wa s u se d, us e 2 m l of t he s il ve r n i t r a te s ol u t ion .

To a pp l y t h e si lve r n it r a t e: 1 . En s u re sa l t ed pa pe r is co m p le te l y d r y .

2 . Ta ke a c lea n g la ss r od .

3 . P u t on g lo ves .

lo w

in ca n des cen t

l ig h tin g, d ra w

t he

4 . Wo r kin g un de r

sol u t ion in to t he s y rin ge .

5 . O n t he pa pe r 2 0 m m o u t f r o m wh e re t he i ma ge st a r t s gen tl y di sp en se a l l t h e so l u ti on on t o t h e pa p e r in a st ra ig h t l in e , s to p pi n g 2 0 m m in f ro m e dge .

6 . Pla ce t he r o d c a r ef ul l y on t he fl u i d a n d wi t h gen tle si de wa r d m o ve men ts a l lo w t he f l ui d t o ev en l y d is pe rs e a lon g t h e f ul l len gt h o f gla ss ro d .

7 . Po si ti on t he ro d be t we en t h e pa pe r e d g e a n d t he so l u ti on .

8 . D ra g t he so l u ti on t o t he o t he r en d of t he p a p e r a t lea s t 2 0 m m be y on d t he i ma ge a rea , b u t s t o p be fo re t he e d ge o f t h e pa pe r . T h e d ra g s h o ul d be a t a con sta n t s m oo t h s tea d y ra te , wi t h ve r y li t t l e p re ss u re . T h is s h o ul d ta ke a b o ut t en sec on ds . I f t h e r e a r e p a r t s o f t h e i m a g e n o t c o v e r e d b y t h e s o l u t i o n i m m e d i a t e l y d r a g t h e s o l u t i o n b a c k o v e r t h i s a r e a t o a v o i d a n u n e v e n c o a t i n g .

T he Sa l t p ri n t M a n u a l | C oa ti n g t he Pa p er 4 0

9 . Aga in g en tl y l if t t h e r o d o ve r t he so l u ti on s o t he r o d s it s

be t we en t h e pa pe r e dge a n d t he l on g po ol o f so l u ti on .

1 0 . Gen tl y p u s h t h e so l u ti on to t he o p p osi t e en d o f t h e pa pe r .

1 1 . If t h e p a p e r is even ly c ove r ed wa i t fo r 3 0 s ec on ds fo r t he

sol u t ion t o a bs o r b i n t o t he pa pe r .

1 2 . T he re m us t en o ug h sol u ti on le f t on t h e pa pe r t o s m oo t hl y

re pea t t he coa t in g a t lea s t 4 t i mes .

1 3 . En s u re t he re a re n o p u dd les of s ol u t ion o r un c oa te d a r ea s .

1 4 . An y ex ces s ca n be re m ov ed gen tl y wit h a pa pe r t o wel ,

a vo id t he i ma ge a re a .

1 5 . Ho ld t he pa pe r b y a c o rn e r a n d a l lo w a n y ex ces s t o r un of f .

1 6 . To d r y ha n g o r la y t he pa pe r s ol u t ion si de u p. A ha i r d r ye r ca n be u se d, kee p t he d r ye r 1 0 c m a wa y f ro m t he pa pe r su r fa ce .

1 7 . D r y in da r k o r l o w l ig h t a rea .

I t is i mp o r ta n t to w a sh t he r od a f te r e ve ry co a t of s il ve r . T he r od be co m es con ta m in a te d wi t h sa l t a s yo u a re coa t in g .

T he s t re n g t h of t he sil ve r n i t ra te sol u t ion re g ula t es t he g r a in si ze o f t he p re c ip i ta ti n g s il ve r c hl o ri de . S t r on g e r so l u ti on s p ro d u ce la r ge r g ra i n s t ha t a re les s li k el y t o a bs o r b in to t he fi b res of t he pa p e r. 40

Coa tin g t he si lv e r n it ra te on to t he d ry s o di u m c hl o ri de c rea te s:

1 . Sil ve r c hl o ri de , t h e i ma g in g ma kin g c o m po u n d .

2 . So di u m n i tr a te , t hi s m us t be wa s he d ou t o f t he p rin t

a ft e r ex po s u re.

S E N S I TI S I N G AL B U M E N P AP E R

o As wi t h t he a lb u m e n sa l t s ol u t ion , i n c rea se t he a m o un t o f sil ve r in t he s y r i n ge o r on t he b r us h t o en s u re ea sy a p pl ica t ion . ( 3 mls f o r 8x 1 0 s hee t ) T hi s a lso he lp s min i m is e t he b u bb les .

o Th e fi r st p us h of t he s il ve r n i t ra t e so l u ti on do wn t h e pa p er sh o ul d b e a t a c on s ta n t s mo o t h s t ea d y ra t e (a bo u t 1 0 sec on ds on a n 8 x 1 0 s h ee t ) Wa i t 3 0 sec on ds be fo re t h e

40 I b i d . p 5 6

T he Sa l t p ri n t M a n u a l | C oa ti n g t he Pa p er 4 1

sec on d „ p u s hin g ‟ of t he si lve r n i t ra te s ol u ti on t o t he en d of t he pa p e r . Gen t l y re mo ve b ub b les b ef o re p us h in g t he sol u t ion a c ros s t he pa pe r . T r y a t le a s t 4 p us hes do wn t he sh ee t. S to p b ef o re t he b u b bl es lea v e a t ra i l of b ub b l es a c ro ss t he pa pe r . E a c h of t he se b u b bl e s on t h e pa pe r wi ll lea v e da r k ci r cle s in yo u r i m a ge .

S E N S I TI S I N G A R R O W R O O T P AP E R

A r ro wr o o t re q ui re s a s t ron ge r s il ve r n i t ra te c oa tin g b u t n e eds to be a p pl ie d ra p id l y d ue to t h e s ta r c h ‟ s s ol u bi li t y . 41 A pp l y t he sil ve r n i t ra te s ol u t i on a s de s c ri be d f o r t he sa l te d pa pe r .

S t or ag e of Se n si ti z ed P ape r .

T he st o ra ge of sen s it i ze d pa pe r d u lls t he p r in t , t he hig h li gh t s los e t he i r c la ri t y a n d t h e re is los s of den s i ty . A lb u m en wi ll sta r t to s h o w yel lo wi n g in t he hi g hl ig h ts . T he a u t h o r t he r e fo re di sc o u ra g es s t or a ge fo r mo re t ha n t wo to t h re e h o u rs . Des pi te t he di sa d va n ta ges rea de r s ma y wis h to us e t h e fo ll o wi n g me t h o ds to in c re a s e s t or a ge ti m es .

o 1 t o 5 % c i t ri c a ci d a d de d to t h e si lv e r

sol u t ion . 42

o Ci t ri c a c i d in t he a l b u men s ol u t ion .

o A pp l y 2 % c i t ri c a ci d s ol u t ion on t o p a p er be fo r e

sa l tin g .

o St o re in a c oo l, d r y , da r k a rea in b la c k p la s t ic

ba g s.

41 I b i d . p 5 7

42 I b i d . p 6 2

T he Sa l t p ri n t M a n u a l | C oa ti n g t he Pa p er 4 2

CHAPTER 7

7. PH OT OG R AM S AN D T H E N EG A TI V E

T a l bo t ‟s fi rs t i m ag e s w ere p ho to g r a ms m a d e b y us i n g o b je c ts s u c h as l e a ves a n d l a c e. T hes e m a d e ne g a ti v e i m ag es o n t h e p a p er . T h es e w e re i n t u r n e x po s e d to c re a te a po s i t i ve i m ag e. I n 1 8 4 0 T a l bo t d is co ve re d t he c a lo t y pe n eg a t iv e w h i le ex p er i m en t i ng o n a pro c es s he t ho ug h t m a y c o m pe t e w it h t he D ag u er reo t y p e . A n i m ag e he ex po s e d i n t he c a m er a w as no t v is i b l e u n t i l h e a d d e d a g a l l i c a c i d s o l u t io n to t he e x po s e d p a p er . T a l bo t ‟s c a l o t y pe l a te n t i m ag e is k no w n as t h e f irs t d ev e lo pe d o u t n e ga t i ve . T his s ig n i f i c a n tl y de c re as e d th e ex po s u re t i me i n t h e c a me r a f ro m ho urs to s e co n ds . 43

to m a k e neg a t i ves

t ho ug h co m p u t er s h as Th e a bi l i t y re j u ve n a t e d m an y p ri n t i ng -o u t p ro ces s es . P ho to gr a p he r s a n d a rt is ts w i t ho ut a c ce s s to l ar ge fo r m a t c a m er as a n d d a r kro o ms c a n no w ex pe r ie n c e t h e ar t a n d cr a f t o f th es e t h e e a rl y p ho to g r a p h ic p ri n t p ro c es s es .

P H O T O G R AM S

i t t o

T he ea r lie st p h o to gra p h i c i ma ges c re a te d we r e p h o to g r a m s . T he i ma ge a c hi eve d b y si m pl y pla c i n g a n o bj ec t on to t he sen si t i ze d pa pe r s u rf a c e a n d e xp os i n g l ig h t . O f ten p ho t og ra m s a re o ve rl o ok ed d ue t o t h e exp os u re p ro b le ms a n d “a r t y” or j uv en i le sti g ma a t ta c he d. O bj ec t s ha ve va r yin g den s i t y a n d ca lc u la tin g t he ex p os u re ti me ca n be p r o ble m a ti c . U su a ll y wi t h p ho t og ra m s it is n o t p oss i bl e t o c he c k ex po s u re s wi t h o u t ris k o f m ov in g t h e ob je c t . T he co lo u r , s ha pe a n d di m en s i on o f t he o bj ec t wi l l ha ve a n a ffe c t on ex po s u re a n d p rin t co lo u r .

o Gla s s o b je c ts s uc h a s va ses a r e of ten n o t s u c ces sf ul in U V l ig h t box es a s t h e l ig h t “ wr a ps a ro u n d ” t he o bje c t .

o T h ree di m en s ion a l ob je c ts in s u n li g h t a l te r a s t he s un

m ove s.

o L ig h t we ig h t ma te r ia ls ex po se d o u ts i de n eed t o b e fi r m l y

fixe d in ca s e of wi n d mo ve men t .

43 S c h a a f , L . J . ( 1 9 9 6 ) R e c o r ds o f t h e D a w n o f P h o t o g r a ph y T a l bo t 's N o t e bo o k s P & Q , U n i v e r s i t y P r e s s C am b r i d g e , C am b r i d g e G r e a t B r i t a i n .

T he Sa l t p ri n t M a n u a l | 4 3

o Col o u rs o f i te m s ma ke a di ff e ren ce to ex p os u re t i me . Re d i t e ms fo r exa m pl e ta ke m o re ti me to ex po se t ha n ye ll o w.

T H E S AL T P R I N T N E G A TI V E

O ft en t he fa i l u re t o p r o d u ce q ua l i t y sa l t p rin t s c o me s f r o m un s u i ta ble n ega t ive s. T h e i dea l sa l t o r a lb u m en p rin t n e ga ti ve ma y n o t p ro d u ce q ua l i t y p r in ts in ot h e r p r in t p r oc es ses . A t te m p tin g t o p r o d u ce a n ega ti ve f o r va ri o us p r in tin g -o u t p ro ce sse s o r p r o ce ssin g - o u t pa pe r s m a y c o m p ro m is e ea c h o f t he p ro ce sses .

in

t h e hi g hl ig h ts a n d

re co r d s mi d

T he lon g t on a l ra n ge of sa l t p rin t s pr ov i des ex ce p ti o n a l sepa r a t io n s to n es pa r ti c ul a rl y we ll . S ha do ws la c k t he sa me de g ree of se pa r a ti on , ma y l o ok m u d d y a n d l a c k de ta i l. A hi g h pe r cen ta g e o f s ha do w a rea i n a n ega ti ve ca n ma ke t he en t ir e i ma g e a p pea r f la t . Exp os in g f o r t he s h a do ws is t he re fo re c ri t ica l . T he re m us t b e de ta il in t he s ha d o ws a n d hi g hl ig h t s wi t h a den si t y ra n g e of 1 . 8 t o 2. 2 (a t lea s t 7 s t op s la ti t u de ) .

t he sha do ws a n d / o r

l os i n g de ta il

in

Sa lt pr in ts d o n o t re q u i re a hi g h c on t ra s t n ega ti ve . T he n ega ti ve m u s t be d en se wi t h in f o r ma ti on f r o m t h e s ha d o ws to t he hi g hl ig h ts . A l o w c on t ra s t n ega t i ve wi ll p r o d uc es a fla t p rin t b u t h ig h c on t r a st n ega t iv e s wi l l re su l t in ha rs h co n t r a st y t he p rin t s, o f ten hi g hl ig h t s .

S uc ce ssf u l sa l t ed pa pe r p rin t re q ui re s :

1 . A n e ga ti ve wi t h a l on g t on a l ra n ge , t h e r a n ge b e t ween

t he hi g hes t a n d l o w es t den si t y p oi n t s ma x i m ise d .

2 . A n ega t iv e wi t h e n o ug h den s i t y t o a l l o w t he si lv e r c hl o ri de to c ha n ge i n t o m e ta l li c si lv e r d u ri n g ex po s u re .

D ue t o li g h t r ef le ct in g o ff t he s u r fa c e , glos s y a l b u men p r in t s see m to ha ve a s h o rt e r de n si t y ra n g e t ha n ma t t pa pe r s . Th e p rin t a p pea r s a s t h o ug h i t h a s dee pe r sha d o ws a n d b r ig h te r hi g hl ig h t s. P ro ce ss ed- o u t pa p e rs ha v e t hi s sa me e ffe c t . A glo ss y g ela t in -s il ve r p rin t wil l a p pea r t o ha v e d ee pe r bl a c ks a n d wh i t e r hig h li g h ts co m pa r e d wi t h a d ull m a t t -f in i s he d p ro ce sse d o u t p rin t . G los s y a l b u m en p r in t s ha ve a co m pa ra bl e to n a l ra n ge t o pla t i n u m p r in ts . Sa l te d pa pe r p rin t s ex ce ed t he

T he Sa l t p ri n t M a n u a l | P ho t og ra m s a n d t h e N ega t ive 4 4

to n a l ra n g e of pla t in u m. 44 Th is i s d ue to t he se lf ma sk i n g effe c t . T h e si lve r c hl o ri d e c on v e r t s to me ta ll ic si lve r d u r in g exp os u re t h u s b lo c kin g t he s ha do w a rea s ( lig h t pa r t o f t he n ega ti ve ). T h is sl o ws t he ex p os u r e a llo win g t he h ig h li g h ts (d en se / da r k p a rt o f t h e n ega t iv e) t o con t in ue p rin t in g . T he self - ma s k in g g iv es p rin t s a gra da t ion o f lig h t to n es wh i le st il l h ol din g go o d s ha do w de ta il . Co r r e c t n ega t ive den s i t y is i mp o r ta n t f o r t he hi g hl ig h t s so t h ese lig h t e r ton e s a re n o t ove r -ex p ose d .

T he sa l te d pa pe rs a n d ma t t (s in g le c oa te d) a l b u men p r i n ts re q u ir e mo r e re d uc ed s il ve r to m a ke t he a p pea ra n ce of b la c k in t h e s ha do ws . T h is is a c h iev e d b y l on ge r e xp os u r e t i m e s, t he re fo r e t he n ee d fo r a den se r n ega ti ve . T he p la in sa lt ed p rin t wi t h o u t a bin de r is t he fla t t es t i n a p pea ra n ce ; t he r e fo re it r eq u i res t h e g r ea t es t den s i ty r a n ge in t he n ega t iv e t o a lle via t e t h is l oo k .

T Y P E S O F N E G A TI V E S :

Al t h o ug h n e ga ti ve s fa ll in to t o t wo ma jo r g ro u p s , a n a l og ue a n d d igi ta l , t he se g r o up s do in te r t win e . An a n a lo g ue n ega t ive ca n be p ro d u ce d f ro m a di gi ta l fi le a n d a n a lo g ue n ega t ive s a re di gi t ise d to c rea t e i n k je t n e ga ti ves . T h ey a ll off e r a d va n ta ges a n d ha v e d isa dva n t a ges .

A N AL O G U E C O N TI N U O U S T O N E F I L M N E G A TI V E S

A dva n ta ges :

o Ne ga ti ves ca n p r ov i de a n ex ce llen t con t in uo us t on e .

o De ve lo p men t con t r ols ca n c r ea te t he ext ra den si t y f o r

sa l t p r in ts .

o Sil ve r n ega ti ve s b l oc k in g po we r s a r e gr ea te r t ha n t he

bla c k dy es o f in kj e t pr in te rs .

D isa dva n ta ges :

o Fil m ma y n o t be rea di l y a va i la bi li t y .

o Re q ui re a da r k ro o m fa c il i ty .

o 3 5 m m a n d me di u m fo r ma t f il m s n ee d to be en la rg ed b y mea n s of in te r - n eg a ti ve s o r rev e rse p ro ce ss in g . T h ese ma te r ia l s a re ex pen siv e. D us t ca n b e a c u rse .

44 R e i l l y , J . M . ( 1 9 8 0 ) T h e A l bu m e n & S a lt e d P a p e r B o o k : T h e H i s t o r y an d pr a c t i c e o f ph o t o g r ap h i c pr i n t i n g , 1 8 4 0 - 1 8 9 5 . , L i g h t I m p r e s s i o n s C o r p o r a t i o n . , R o c h e s t e r , U S A . p 6 9

T he Sa l t p ri n t M a n u a l | P ho t og ra m s a n d t h e N ega t ive 4 5

T he n u m be r o f bla c k a n d wh i te f il m s a va i la b le on t h e ma r ke t to da y ha s r ed u ce d con s i de ra bl y d ue t he i n c r ea se of di gi ta l ca p t u re ca me ra s . S he et fi l m a va i la bil i t y in A us t ra lia is q ui t e li m it e d. (Se e s up p li er l is t ) T he c ho ic e is wi de r in 3 5 m m a n d i n te rn a ti on a l ma r ke t of fe rs a m o re 1 2 0 ro ll fi l ms . T he ext en s ive ra n ge .

Fil m ex p o s u re a n d t on a l ra n ge ca n b e con t r ol le d b y t h e fol lo win g :

1 . L ig h tin g o f t he s u b j ec t .

2 . T he t y pe of f il m us e d .

3 . T he d eve lo p m en t t i me a n d a g i ta ti on .

4 . T he t y pe a n d s t ren g t h o f t h e de ve lo pe r .

I ha v e

tes t in g

fo un d

Th e sa l t p r in t n ega ti ve m us t be ex po se d fo r t he s ha d o ws . T he st re n g t h of t he de v elo pe r s ol u ti on is do u b le d t o p ro vi de t h e den s i t y. T h ro u g h exten si ve t he I lf o rd ‟s HP 4 f il m a n d PM K de vel o pe r to co m b in a ti on o f p ro d u ce t he bes t sa lt p rin t n e ga ti ves t o da te .

I L F O R D F P 4 F I L M 1 2 5 I SO

T his fi l m wi l l c r ea t e a wi de t on a l ra n g e ex ten de d b y t he lo w fo g ba se o f t he f il m . U s e t h e 1 2 5 ISO ra t in g a n d ex po se f o r t h e sha d o ws .

PMK DEVELOPER45

7 5 0 ml 1 0 g m 2 0 g m 1 0 0 g m 1 0 0 0 ml 1 4 0 0 6 0 0 g m 2 0 0 0 ml

S ol u ti on A D is ti lle d wa te r a t ro o m t e m pe ra t u re M et ol So di u m bi s ul fi te P y ro ga l lo l Wa t e r t o m a ke S ol u ti on B D is ti lle d wa te r a t ro o m t e m pe ra t u re So di u m m e ta b o ra te Wa t e r t o m a ke M et h o d: S t oc k S ol u ti o n A 1 . Weig h o u t t h e so di u m bis u lf i te .

45 H u t c h i n g s , G . ( 1 9 9 2 ) T h e B o o k o f P y r o , B i t t e r D o g P r e s s , G r a n i t e B a y , C A . p 1 3

T he Sa l t p ri n t M a n u a l | P ho t og ra m s a n d t h e N ega t ive 4 6

2 . A dd a pi n c h o f t h e so di u m bis u lf i te t o t h e 7 5 0 ml o f wa t er

a n d se t t he re ma in d er a s i de .

3 . A dd t he me t ol a n d s ti r un t il c o m pl e tel y di sso lv ed .

4 . A dd re ma in i n g s od i u m bis u lf i te , s ti r un ti l d iss ol ve d .

5 . If yo u do n o t ha v e a ven t ila t in g ho o d, p er fo r m t he f oll o wi n g

o u tsi de .

6 . P u t on g lo ves , ma s k a n d ey e p r o te c ti on .

7 . M ea s u re o u t t he p y r oga ll ol a n d a d d to t he s ol u t ion .

S t oc k S ol u ti o n B

1 . D iss ol ve t he so d i u m me ta bo r a te in t he 1 4 0 0 ml of wa te r .

2 . A dd wa t e r t o m a ke 2 0 0 0 ml .

St o re in b ro wn gla s s bo t t les cle a rl y ma r ke d .

U sa ge f o r sa l t p rin t n ega ti ve s on l y :

Sal t pri nt ne g a ti ve :

1 . Hea t wa te r 5 0 0 ml t o 2 2 ° C .

2 . A dd 1 0 ml pa r t A .

3 . A dd 2 0 ml pa r ts B .

4 . P ro ce ss f il m wi t h co n ti n ua l a g i ta ti on f o r 1 2 m in u te s .

5 . St o p ba t h 3 0 se c on d s (n o r m a l a ci d s to p ba t h ) .

6 . Fix fo r 5 m in u te s a gi ta ti on fo r 3 0 se con ds e ve r y m in u te .

(S ta n da r d rea d y- ma de a m m on i u m t h ios ul fa te f ixe r ) .

7 . D o n o t ta n t he n ega ti ve a s o f ten s ug ges te d b y pla cin g ba c k in t o dev el op e r a f te r f ixin g . T hi s fla t t e n s t he t on es fo r t h e sa l t p r in t.

8 . Wa s h fo r 1 mi n u te .

9 . Pla ce in a ba t h of 1 % c lea rin g a ge n t f o r 2 m in u tes ( 1 0 g m

so di u m s u l p hi te i n 1 0 0 0 ml wa t e r) .

1 0 . Wa s h fo r 5 mi n u te s .

1 1 . A d r o p of we t t in g a gen t in 1 0 0 0 ml wa t e r f o r 1 m in u te s t o ps

st re a k ma r k s .

O the r Fi l m s

T he Sa l t p ri n t M a n u a l | P ho t og ra m s a n d t h e N ega t ive 4 7

1 . I L F O R D H P 5 4 0 0 ISO . Si mi la r q ua li t ies t o t h e I lf o rd FP 4 fil m , b u t wi t h o u t s u c h a clea r fi l m ba se . P r oc ess a s a b ov e b u t in c re a se t he dev el o p men t ti m e t o 1 2 m in ut es

2 . F O M A P A N C L A S S I C 2 0 0 I SO . T h is fi l m wo r ke d wel l wi t h si m il a r q ua l i tie s t o t he I lf o r d F P 4 . T he ba se fo g a n d PM K de vel o pe r wa r m ed t he n e ga ti v e ba se co lo u r . T hi s fla t ten s t he s a l t p ri n t to n a l ra n ge . P r oc e ss t he f il m a s a b ove b u t i n c r ea s e t he de vel o p men t ti m e t o 1 2 m in u tes .

I N C R E AS I N G TH E T O N AL R AN G E P O S T D E V E L O P M E N T

Fil m R ed u c in g Fo r m u la s p r ov i de d on l y a min i ma l i n c re a se i n t he ton a l ra n g e .

Sele n i u m wa s s u c c essf u l a s a f il m i n ten si fy in g f or m u l a . A sol u t ion o f 1 : 1 0 fo r 1 0 mi n ut es in c rea s ed t h e t on a l ra n ge b y 2 st o ps , d ue t o sel en i u m a d din g den si t y t o t he h ig h lig h t s .

E N L AR G I N G N E G AT I V E S I N TH E D AR K R O O M

En s u re y o u r da r k r o o m is li g h t t ig h t a n d y o u r e n la rg e r d oe s n o t re fle c t l ig h t a ro un d t h e r oo m . T h is st o ps t h e r is k o f l ig h t fog gin g ex pen s ive f il m . W hi te ba se d e a sels s h o ul d b e co ve re d wi t h a bla c k s he e t of pa pe r to st o p lig h t ref le c tin g b a c k t h ro u g h t he f il m . Th e o r t h o fi l m a n d l i t h f il m a re hi g h con t ra s t s o d il u te d pa pe r d eve lo p er is use d t o lo we r t h e con t ra s t.

3 5 m m a n d 1 2 0 ro ll fil m s ca n be en la r ged in t he d a rk r o o m b y ma k in g a n en la rge d in te r- p os i ti ve t hen c on ta c t p rin t in g b a c k to a n e ga ti ve o f t h e sa me si ze . T h is i s a t wo s t ep p ro ce ss .

In te r- p osi t iv es me t h od of en la rgi n g n e ga t iv es :

o U sin g Il fo r d O r t h o Pl u s fi l m. T his m u s t b e u se d un d e r a

re d sa fe li g h t .

1 . Pla ce t he 3 5 m m o r 1 2 0 ro ll f il m in t he en l a rge r a n d c he c k t h e f o c u s e t c , a s fo r n o r ma l da r k ro o m p rin t in g .

2 . U se tes t s t ri ps t o f in d t he co r r ec t e xp os u r e. i n d il u te d pa pe r de ve lo pe r . S of t un d il u te d wi ll

P ro ce ss t h is de vel o pe rs s u c h a s Ko da k Sel ec t ol giv e go o d h ig h li g h t a n d s ha do w de ta il .

3 . A dj u st t h e ra ti o o f t he de ve lo pe r t o con t r ol t h e

con t ra s t.

4 . Wh en t h e n e w po si ti ve i s d r y pla ce t hi s on n e w

te st s t r i p fi l m .

T he Sa l t p ri n t M a n u a l | P ho t og ra m s a n d t h e N ega t ive 4 8

5 . Exp ose de te r m in e t he ex p os u re ti m e .

6 . Con ta c t p r in t t h e n e ga t iv e.

7 . Tes t t h is n e w n eg a t ive to en s u r e yo u h a ve n o t lo s t

t he ton a l ra n g e , o r ga in e d to o m uc h co n t ra s t .

o U sin g M a c o Gen i u s fil m : T h is ca n be us ed un de r a re d

sa fe l ig h t .

1 . Pla ce t he 3 5 m m o r 1 2 0 ro ll f il m in t he en l a rge r a n d c he c k t he f o c u s , e t c . a s f o r n o r m a l da r k r oo m p rin t in g .

2 . U se tes t s t ri ps t o f in d t he co r r ec t e xp os u r e. P ro ce ss t hes e in di l u te d pa p er de v elo pe r . S of t 1 : 2. Fo r 2 de vel o pe rs s uc h a s K o da k S ol ec t ol m in u tes . Ad j us t t he ra t io of t he d eve lo pe r t o con t r ol t he con t ra s t .

3 . Wh en t he n e w p os i t ive is d r y , p la ce t he po si t ive in di re c t con ta c t wi t h tes t s t r ip s t o d e t er m in e t he co r re c t ex p os u re .

4 . Con ta c t p r in t t h e n e ga t iv e .

5 . Tes t t h is n e w n eg a t ive to en s u r e yo u h a ve n o t lo s t t he t on a l ra n ge o r t ha t i t ha s ga in e d to o m u c h con t ra s t.

DI G I TA L N E G A TI V E S

A kin to a n a l og u e f il m , t he a m o un t o f in fo r m a ti on a n d t he q ua l i t y o f t h e dig i t a l fi le wi l l ref le c t in t h e o u t co m e o f t he fin a l p rin t . T h e ref o re t h e me t h o d of s ca n n in g o r ca p t u rin g a di gi ta l i ma ge in ca me ra m u s t be c on s id er e d. A pr of ess io n a l p ho t og ra p h ic la b o r dig i ta l b u r ea u wi ll offe r q ua l i ty s ca n n in g se rv ic es . An 8x 1 0 n ega ti ve s ca n n e d a t 4 0 0 p pi wi l l gi ve a fil e si ze of 3 6M B . D ig i ta l ca me ra s a r e be yon d t he s co pe of t his bo o k d ue t o t he c o mp lex a n d con s ta n tl y c ha n gi n g ma r ke t . Al t h o ug h n o t di s c u sse d, t he ca p t u re d i ma ge f ile s ho u l d h a ve si mi la r q u a li t ies t o t he re fe r re d s ca n n e d fi le a bo ve .

D igi ta l n ega t iv es in cl u de :

I n k j e t n e g a t i v e s f r o m d i g i t a l f i l e s

1 .

In k je t n ega t iv es

a )

b ) In k je t s pe c t ra l n e ga ti ve s

c) Pa pe r in k je t n ega t iv es

d) L a s e r p r in t n ega t ive s

T he Sa l t p ri n t M a n u a l | P ho t og ra m s a n d t h e N ega t ive 4 9

An a l og u e Ne ga ti ve s fr o m Di gi ta l Fi les

a ) Ko da k D u r oC l ea r™ s pe c t ra l n e ga ti ve

b ) I ma ge S e t te r fi l m

SP ECT R AL N EG AT IV E S :

A n a me use d t o de s c ri be f il m t ha t u ses co lo u r to t ra n s m i t o r b lo c k d iff e ren t wa ve len g t h s rea c hin g lig h t s en si t i ze d pa p er .

Salt print

Spectral negative

In 1 8 7 3 W .H . V og el dis c ov e re d sen s it iv i t y to gr een wa s en ha n ce d by a d d in g ye ll o w d ye t o co ll o di on pla t es . He s uc ce ss f ull y t ri ed r e d to a bs o r b t he g re en l ig h t a n d g re en to a bs o r b t he re d. T his di sc ov e r y ha d a n e n o r mo u s a ff ec t on t he f u t u r e of bo t h b la c k a n d wh i te a n d c ol o u r p ho t og ra p h y . In b la c k a n d wh i t e p ho t og ra p h y g reen , ye ll o w, o ra n ge a n d re d li g ht d is t o r t t he to n e va l u es . F o r e xa m p le r ed i s di ff i c ul t to t el l a pa r t f r o m bla c k . 46 M os t p h o to g r a p hi c p r o cess es a r e sen s i ti ve f ro m 3 0 0 to 5 0 0 n a n o me t r es in cl u di n g u l t ra v io le t , vi ole t a n d bl ue . T he i s se n si ti ve t o t h e el e c t ro ma gn e t ic sp ec t r u m h u ma n ey e be t we en 4 0 0 a n d 7 0 0 n a n o me t res .

Fil te r s in bla c k a n d wh i t e p h o to g ra p h y wo r k b y a bso r bin g un wa n t ed c ol o u rs of l ig h t . T he s lo p e of t h e c ha ra c te r is ti c c u rv e a n d t he c o n t r a st o f t he i m a ge ca n be c ha n ge d b y t h ese co lo u r ed f il te r s . 47 Fo r exa m pl e r e d fi l te r s a bso r b a p ro p o r ti on of t he b l ue da yli g h t . T he s pe c t ra l n e ga t ive wo r k s on t he sa me p rin ci pa l. Co lo u r s con t r ol t he t on a l r a n ge by t he q ua li t y a n d q ua n ti t y of l ig h t re a c hi n g t he l ig h t s e n si ti ve pa pe r. A lt h o ug h t hi s a c ts a s a den s it y s o me wh a t si m il a r t o si lve r pa r ti cle s in fil m , i t do es n o t ha ve t he sa me s u b tle to n a l g ra d ua ti on s whi c h fil m o ff e rs . T his i s m o re p r ob le ma t i c i n hig h li g h ts a n d s h a do w re gi on s .

No t e t ha t p ig m en t i n ks , u l t ra c h ro m e in ks a n d d ye - ba s e d i n ks in in k je t p r in te rs ma ke a c on s i de r a bl e di ffe r en c e t o t h e n ega ti ves den s i t y a n d t on a l ra n ge. G e n era ll y d y e ba s ed i n ks p ro d u ce a wi d e r ga m u t o f c ol o u r a n d a hi g he r res ol u t ion , t he in k si ts in t he s t r u c t u re o f t he fil m . T he pi g men t in k si t s on

46 Ke n n e t h - M e e s , C . E . a n d J am e s , T . H . ( 1 9 6 6 ) T h e T h e o r y o f t h e P h o t o g r a ph i c P r o c e s s , T h e M a c m i l l a n C o m p a n y , N e w Y o r k .

47 S t r o e b e l , L ., C o m p t o n , J . , C u r r e n t , I . a n d Z a k i a , R . ( 1 9 8 6 ) P h o t o g r a ph i c M at e r i a ls a n d P r o c e s s e s , B u t t e r w o r t h P u b l i s h e r s , S t o n e h a m , M A , U S A .

T he Sa l t p ri n t M a n u a l | P ho t og ra m s a n d t h e N ega t ive 5 0

t he s u r fa ce o f t he fil m . P ro d u ce rs of t h es e in k p ro d u c ts a c cla i m a n ex te n d e d l ife . T h e dy e - ba s ed i n k s a bil i t y to b lo c k U V l ig h t i s g rea te r t ha n t he pig m en t b a s ed in k s. 48

T he re a re n u me r o us a pp r oa c hes in m a k in g d ig i ta l n e ga ti ve s . I fo un d M a r k Ne ls on ‟ s P re c is io n D ig i t a l Neg a t i ves bo o k u se fu l . His s y s te m e m po we rs yo u t o c us t o m ise yo u r co m p u te r s ys t em , to c re a t e n eg a t iv es in a n u m be r o f o u t p u t m od es t ha t wi l l s ui t yo u r pa r ti c u la r p ro ces s . T h is in c l ud es in k je t , i ma g e se t te r o r Ko da k D u r a c lea r ™. T he s te p - we d ge t ha t ca n be p u r c h a sed wi t h h is bo o k is a v a l ua b le to ol .

T R A N S M I S S I O N S T E P W E D G E S

T ra n s m iss ion s te p- we d ges a i d in ton a l ra n g e co m pa r is on s a ga in s t n ega t ive s. B y e x po s in g t h e ste p - we dg e b esi d e t he n ega ti ve i t hel ps t o in d i ca te t h e t on a l ra n ge in t h e ex p ose d p rin t , a s sis t in g in ca l c ul a tin g f u t u r e ex pos u r es . T he st ep we d ge is f ul ly ex po sed wh en t h e f i rs t s te p is t he sa me d en si t y a s t he ex pos e d pa pe r o u ts id e t he n ega t i ve a re a . T h is s ho u ld be j us t b ef o re br on zi n g o c c u rs . T h is wi ll he l p t o fin d :

o T he t on a l sca le o f t he ex po se d pa pe r in di ca te d by

t he n u m be r o f se pa r a te s t ep s vi si bl e .

o

If t he n e ga ti ve ha s t he sa m e ton a l s ca l es a s t h e s te p we d ge .

T ra n s m iss ion s te p- we d ges a ls o kn o w n a s g r ey s ca l es o r st ep ta bl et s . T hes e a re a va i la b le i n a n u m b e r o f s te ps b u t t he m os t co m m on l y us ed i s 2 1 s te ps . T hi s is a s t ri p o f fil m in s t ep s o f exp os u re s, ea c h s te p in c rea sin g t he de n si tie s b y 0. 1 5 . T h ese a re a va i la ble f ro m St o uf fe r o r t he y ca n b e c r ea te d on yo u r co m p u te r wi t h P ho t os ho p ™ a n d p r in te d on cl ea r fi l m s u c h a s Ag fa Co p y J e t o r Pi c to r i co T S P 0 0 usin g a n in k je t p rin te r .

As wi t h fi l m p rin t in g t he e m u ls ion to e m ul si on r ule st il l a p pl ies . F li p t he i m a ge ho r i zon ta ll y be f o re yo u p r in t t he in k je t n ega ti ve t o a v oi d l os s of s h a rpn ess in t he p rin t . T his ca n be ca r rie d o u t in P ho t os ho p ™ o r t he p r in te r ‟s p ro pe r t ies c us to m s se tt in g s.

48 N e l s o n , M . I . ( 2 0 0 4 ) P r e c i s i o n D i g i t a l N e g a t i v e s : F o r S i l v e r & O t h e r A lt e r n at i v e P r o c e s s e s , M a r k I N e l s o n . p 5 2

T he Sa l t p ri n t M a n u a l | P ho t og ra m s a n d t h e N ega t ive 5 1

D E N S I TY R E A D I N G S O N A D E N S I TO M E TE R

Den si t y i s t he mea su r e o f li g h t t ha t pa s ses t h r o ug h t he n ega ti ve . ( kn o wn a s t ra n s m is si on den s i t y ). L ig h t re fl ec t in g fr o m p rin te d ma te r ia l i s kn o wn a s re f lec t ed den si t y . T he den s i to m e te r g ive s set va l ue s t o t h is t r a n s m it t ed a n d re fle c te d l ig h t a l lo w in g a c on s is ten ce co m pa ri son .

Wha t eve r n e ga ti ve ty pe yo u c ho ose , do n o t b ec o me ob ses se d . Fin d t he p ro ce ss t ha t fi ts y o u r wa y of p r in tin g. D o n o t be t he pe rs on who en ds u p wi t h a t ec hn i ca l ly pe rf ec t

i ma ge t ha t i s de vo i d of a ll s o ul , in s p i r a ti on a n d i ma gin a t i on .

T he Sa l t p ri n t M a n u a l | P ho t og ra m s a n d t h e N ega t i ve 5 2

CHAPTER 8

8. E X P OS IN G TH E P RI NT

T h is is t h e c h a l le ng i ng a n d e x c i t in g p a rt o f t h e p ro ces s . W h i le ex po s i ng n eg a t i ves o n t he s e ns i t i ze d p a p er yo u c a n o bs er ve yo ur i m ag e as i t a p p e ar s . Yo u h a ve co n tro l o ve r t he i n te ns i t y o f t he li g h t a n d t h e l en g t h o f e x po s ur e w hi c h a f f e cts t he c o lo ur a n d de ns i t y o f t he f i n a l p r i n t.

The s a l t p rin t re q ui r es ul t ra vi ole t (U V ) li g h t to f o r m a n i ma ge . T he s un o r a lt e rn a ti ves s u c h a s la mp s o r t u be s e m i t tin g U V li g h t ca n be u se d . T he l ig h t s o u r ce s ess en tia l f o r p rin tin g - o u t p ro ce sse s a r e a mi ll ion ti m es s t r on ge r t ha n t hos e fo r de vel o pe d- o u t p r o ces s es . 49 P ho t og ra p hi c en la rg e rs ca n n o t p ro d u ce en o ug h l ig h t f o r p r in tin g - o ut p ro ce sse s .

T he co lo u r a n d co n t ra s t o f t he p r in t is in f l uen ce d b y t he in t en si t y a n d c ol o u r of t h e e xp osin g li g h t. A U V l ig h t b ox of f er s s ta b il it y a n d r epea ta b il i ty wh i le s un l ig h t ‟s U V exp os u r e s a re v a r ia b le a n d co m p lex .

S un l ig h t wi ll a ff ec t t he c ol o u r a n d con t ra s t o f t he p rin t a s it is ex po si n g de pen d in g on :

o Ti me of t he da y.

o Ti me of t he yea r .

o H u mi di t y .

o Clo u d co ve r .

o D i re ct s un li g h t , t hi s giv es les s c on t ra s t a s t h e ex pos u r e

is fa s t e r.

t hi s

in c rea ses con t ra s t a s

t he

o

In di re c t s un l ig h t , exp os u re is sl o we r .

o A m bien t t e m p e ra t u r e wil l a ls o a f fe ct s en si ti vi t y of t he exp os in g p r in t wi t h l i t t le r ed u c t ion of si lve r ta k in g pla ce b e lo w 5 ° C .

49 W ar e , M . J . ( 1 9 9 4 ) M e c h an i s m o f I m ag e D e t e r i o r a t i o n i n E a r l y P h o t o g r a p h s - t h e s e n s i t i v i t y t o L i g h t o f W H F T a l bo t ' s h a li de - fi x e d I m a g e s 1 8 3 4 - 1 8 4 4 , S c i e n c e M u s e u m a n d N a t i o n a l M u s e u m o f P h o t o g r a p h y , F i l m & T e l e v i s i o n , B r a d f o r d , L o n d o n . p 1 7

T he Sa l t p ri n t M a n u a l | 5 3

lev els of U V a n d wi ll l eve ls

lig h t

o D iff e ren t vis i ble gen e ra te di ffe r en c e s.

lig h t

up

Al t h o ug h t he ef fe c t o f li g ht on t h e sa l t p rin t ma xi m ise s in t he re gi on of t o 3 8 0n m , vis i ble a p p rox i ma te l y 6 5 0n m wi l l re d uc e sil ve r c h lo r id e to me ta ll i c s il ve r . T h e sp ec t r u m bel o w 3 8 0n m a lso r ed u c es t he re d u c ti on o f si lv e r b u t n o r ma l p ic t u r e f ra me gla s s d oes n o t t ra n s m i t li g h t un de r 3 4 0 n m .

t he y r e ma in

t he pa pe r .

An ex pos u r e f ra me , a ls o ca l le d a co n ta c t p r in t fr a me is m a d e u p f r o m 3 pa r ts ; t he f r a me , g la s s a n d a r e mo va bl e h in ge d ba c k . T he f r a me h ol ds t he gl a ss in p la c e a n d t h e hin ge d ba c k a p pl ies p res s u re on t he pa pe r a n d n e ga ti v e t o s t o p mo ve m en t , en s u rin g in con ta c t a n d r egi s t ra ti on wh i le exp os in g . T he fo ll o wi n g s t ep m u s t b e ca r rie d o u t in s u b d ue d lig h t . M a k e s u re t h e sen s i ti ze d pa pe r is d r y o r t h e n e ga t ive wi l l be de s t ro ye d wi t h b ro wn s il ve r n it r a t e s ta in s . T he gla s s m u st b e clea n a n d f ree f r o m d us t be fo r e p la cin g t he n e ga ti ve , fol lo we d b y t he pa pe r on to t he gl a ss . Pos i ti on t he fil m em u ls ion to pa pe r e m u lsi on . P la c e t h e hi n ge d ba c k o n t o p a n d sec u r e. T u rn t he f r a me ove r a n d c h ec k b ef o re ex po sin g ma ke su r e n o ma r ks o r d us t ha s a p pea re d a n d t h e n ega t iv e is in t he I f y o u ha ve di ff i c ul t y co r re c t p os i ti on on po si t ion in g t he fi l m a n d pa pe r , re mo va bl e t a p e ca n b e use d to a t ta c h c o rn e r s of t h e f il m on to t he pa p er ; t his ca n be re m o ve d on c e po si t ion e d . T he hin ge d ba c k a ll o ws yo u to i n s pe c t yo u r p rin t wi t h li t t le r is k o f de r eg is te r in g t h e f i l m .

f ra m e

t he exp os u r e

t he s un li g h t,

in

Wh en pla cin g t he di ffe r en c e in te m p era t u r e b et ween t h e co ol gla ss a n d t he en ca s e d sen s i ti ze d pa pe r c r ea tes a h u m id i t y c ha m b e r. T his ma y de re gis t e r t h e ima ge a s t he fil m a n d pa pe r e xp a n d a t di ffe r en t ra te s . I t will g ive t he i m p res s ion of a so f t o r o u t of fo c us i ma ge . 50

Ch ec k p rin t ex po s u re s un de r s u b d ue d lig h t . T his s h o ul d be b ri g h t en o ug h to m a ke a de ci si on on t he ex p os u re b u t n o t so b ri g h t t ha t i t con t in ue s to ex p ose t he p rin t . A l wa ys v ie w u n de r t he sa me li g h tin g c on d i ti on s . T h is k ee ps a c on si s ten c y when j u dg in g ex po s u res .

50 R e i l l y , J . M . ( 1 9 8 0 ) T h e A l bu m e n & S a lt e d P a pe r B o o k : T h e H i s t o r y an d pr a c t i c e o f ph o t o g r ap h i c pr i n t i n g , 1 8 4 0 - 1 8 9 5 . , L i g h t I m p r e s s i o n s C o r p o r a t i o n . , R o c h e s t e r , U S A . p 7 3

T he Sa l t p ri n t M a n u a l | E xp os in g t he p r in t 5 4

E X P O S U R E TI M E S

J u dg in g t h e ri g h t e xp os u re ca n b e di ff ic u l t. T he p r in t m u st b e exp ose d b ey on d wh a t a p pea r s t o be t he c o r re c t e xp os u r e b y a bo u t t wo s to p s . Th e fix e r r e mo ve s a p p rox i ma te l y t w o t o t h ree s t o ps of den s i t y, b u t a s t he i ma ge d r ies i t rega in s on e to t wo s to ps in den si t y . Pe r son a l ex pe ri e n ce i s t h e be s t g ui de to un de rs ta n d in g t h e co r re c t ex po s u re. D od gin g ca n be ca r ri ed o u t b y c ut t in g s ha pes t o c ov e r a r ea s on t he n ega ti ve whe r e less e xp os u r e is re q ui r e d. T hese a r e la i d on t op of t he g la s s in t he e xp os u re f ra me a n d mo ve d f re q u e n tl y t o a v oi d dis t i n c t o u tlin es o f t h e d o d gin g t oo l s ha pes .

L I G H T S OU R C E

T I M E

U V l i g h t b o x * 1

1 5 t o 3 0 m i n u t e s

D i r e c t S u n m i d d a y

1 0 t o 2 0 m i n u t e s

I n d i r e c t s u n o r d u l l d a y

3 0 m i n u t e s t o 3 h o u r s

* 1. B a s e d o n a b a n k o f 1 7 P h i l i p s A c t i n i c B L 4 0 w a t t m e r c u r y v a p o u r f l u o r e s c e n c e U V t u b e s a t a d i s t a n c e o f 2 0 c m f r o m t h e p r i n t . T h e s e t u b e s e m i t U V A f r o m 4 0 0 t o 3 2 0 n m p e a k i n g r o u n d 3 6 0 t o 3 8 0 n m .

A di ff us e r o f o pa q ue t ra c in g pa pe r o r g r o un d g la s s c a n be us ed ove r t he ex p o su r e f ra mes i n a U V lig h t b ox to in c r ea se t he con t ra s t.

T he ex po s u re ti me s a re de pen den t on a n u m be r of va r ia ble s :

1 . Ne ga ti ve d en s it y .

2 . Bin de r t y pe , fo r e x a m pl e pla in sa l te d pa pe r i s fa s te r t ha n

a lb u m en b eca u se o f t he c oa tin g .

3 . A dd i ti ves s u c h a s p o ta ss i u m di c h r o ma te wi ll

in c rea s e exp os u re ti m e b u t so di u m ci t ra te wi ll dec r ea se s exp os u r e ti m e .

R E C I P R O C I TY F A I L U R E

Sl o we r e xp os u re s i n c rea s e t he con t ra st of t h e i ma ge , f a st exp os u re s de c rea s e t he c on t ra s t . T he ex t re me s o f e i t he r of t he se wi ll ca use re c ip r o ci t y fa i l u re .

Hig h in ten s i t y re ci p ro c it y fa i l u re ca n oc c u r i f t h e i ma g e is exp ose d di re c t l y t o hi g h U V c on ten t i n b ri g ht s un l ig h t . T h e p ho t o l y sis a c ti vi t y de c rea s es a n d t he s ha do ws wi ll n o t p ri n t a s

T he Sa l t p ri n t M a n u a l | E xp os in g t he p r in t 5 5

da r k o r de n se a s i n t he lon ge r e xp os u re s . T he los s o f t he den s i t y in t he s ha d o ws fla t ten s t he to n a l ra n ge a n d de c re a ses t he con t ra s t.

L o w in t en si t y re c i p ro c it y fa i l u re oc c u rs w i t h a n e x t re me l y we a k l ig h t so u r ce ; a s t he l on g e r p ri n ti n g t i me c r ea tes ve r y sm a ll , v u ln e ra bl e silv e r pa r ti c les , t h e size o f t h e pa r ti cle s re la tin g t o t he len g t h o f t h e ex po s u re . 51

I t ha s been fo un d t ha t o n l y a bo u t 2 % of t he o r ig in a l a p p lie d sil ve r re m a in s on t he pa pe r . Wi t h pa r t ic les si ze s a t a b o u t on e 1 / 1 0 0 of a s il ve r ge la t in p r in t, t he sa l t ed pa pe r p r in t is a t ri s k to a n y i m p u r i tie s. 52

S E L F M AS K I N G

T he sa l t p rin t „ sel f - ma s ks ‟ in t he s ha d o ws , t h e re d u ce d me ta l li c si lve r bl oc k s t he da r ke r t he sha d o w, t he s ma lle r t h e a m o un t of li gh t t ha t rea c he s t he un ex p o sed s il ve r c hl o ri de t h r o ug h t he re d u ce d me ta ll ic sil ve r . T h e l ig h t er a r ea s con t in ue t o ex p os e n o r ma ll y . I t is t hi s se lf - ma s k in g t ha t p ro d u ces t he e x ten de d ton a l ra n ge o f t he sa l t p r in ts . 53

B R O N Z I N G

B ron z in g me a n s t he pa r ti cl es of re d u c ed me ta ll i c si lv e r h a ve m ig ra te d to t he s u r fa c e fo r m in g a la ye r on t he s u rf a c e of t he p rin t . T h is i s t he sa t u ra t ion p oin t whe r e t h e p r in t is ove r exp ose d . D u rin g ex po s u re t hi s br on ze gr een i s h b ra ss y b r o wn sh een a pp ea rs on p rin t s . 54 V er y l ig h t b ron z in g i n t h e i m a ge wi l l d isa p pea r d u r in g p ro ce ssin g . Co n ti n uin g t h e ex p os u re c rea te s a dee p b r on z in g wh i c h wi l l re ma in in t he i ma ge sha d o w r eg ion s a ft er p r o c es sin g. T h is s po ils t he p r in t. I f a n ega ti ve ha s co r r ec t den s i ty , a n d b r on zin g ha s f o r m e d in t he ma r gin s t h e p r in t is a t i ts ma x i m u m den s i t y. W i t h s ui t a bl e n ega ti ves e x p os u re ca n be mon i to re d b y vie win g t he ma r gin s o u tsi de t he n ega t iv e a rea so t he re i s li t tl e n e ed to o pen t h e exp os u re f ra mes .

51 W ar e , M . J . ( 1 9 9 4 ) M e c h an i s m o f I m ag e D e t e r i o r a t i o n i n E ar l y P h o t o g r a p h s - t h e s e n s i t i v i t y t o L i g h t o f W H F T al bo t ' s h al i d e - f i x e d I m a g e s 1 8 3 4 - 1 8 4 4 , S c i e n c e M u s e u m a n d N at i o n a l M u s e u m o f P h o t o g r a p h y , F i l m & T e l e v i s i o n , B r a d f o r d , L o n d o n . ,p 2 4

52 I b i d . p 2 5

53 C r aw f o r d , W . ( 1 9 7 9 ) K e e pe r s o f t h e L i g h t , M o r g a n & M o r g a n , I n c ., N e w Y o r k , U S A . p 1 5 1

54 R e i l l y , J . M . ( 1 9 8 0 ) T h e A l bu m e n & S a l t e d P a p e r B o o k : T h e H i s t o r y a n d pr a c t i c e o f ph o t o g r ap h i c pr i n t i n g , 1 8 4 0 - 1 8 9 5 . , L i g h t I m p r e s s i o n s C o r p o r a t i o n . , R o c h e s t e r , U S A . p 7 3

T he Sa l t p ri n t M a n u a l | E xp os in g t he p r in t 5 6

t h e p rin t a l lo ws

A 2 1-s t ep t ra n s mi s sion we d ge i s use f ul t o in cl u de wi t h yo u r p rin t wh i le ex po sin g yo u r n eg a ti ve. C h ec kin g t h e ex p ose d st ep we d ge a ga in s t i n fo r me d j u dge m en ts t o be ma de a bo u t f u t u re exp os u re s a n d t he n ee ds of t h e n e ga ti ve .

I S

W H A T O C C U R S W H E N TH E S E N S I TI Z E D P AP E R E X P O S E D T O L I G H T

Wh en t h e p r in t is ex po se d t o l ig h t :

o L ig h t a c t in g o n t h e sil ve r c h lo r id e di sa ss o cia te s t h e sil ve r a n d t he c h lo ri de a n d in s o do i n g rele a s es s ma ll pa r ti cl es o f si lve r m eta l.

o Si m u l ta n e o usl y f r ee c h lo r in e m ole c u les a re re lea s ed .

o T he c hl o rin e a b so r b er s a re m ois t u r e in t he pa pe r fi b res , a n d t he ex ces s s il ve r n i t ra t e rea c ts wi t h t he re lea se d c hl o rin e fo r m in g m o re si lv er c hl o ri de .

o L ig h t c on tin u es t o b rea k d o wn t hi s n e w s il ve r c h lo r id e c rea ti n g mo r e m e ta l li c si lve r a n d t he c y cle co n t in ue s . 55

Wi t ho u t lig h t , s p on t a n eo us re d u c ti on o f me ta ll ic si lve r c rea te s a yel lo w co lo u r . T h is c on si s ts o f re d u ce d m e ta l li c si lve r in a fin e l y di vi d ed s ta t e (sl o w ex p os u r e s in c rea se c on t ra s t by c rea ti n g f in e r s il ve r ) a c ce le ra te d b y wa r m t h a n d h u m i di t y . 56 If t he re d u c ti on of s i lve r co n tin ue s t he co lo u r wi l l c ha n g e t o re d /b r o wn a n d fin a ll y a f te r a pe r io d o f mon t h s , t he p r in t ma y a c t ua l l y h a ve a b ron ze d a p pe a ra n c e .

f o r m in g

t in y pa r ti c les co m b in e ,

la rge r pa r t i cle s T hese c he m is ts ca ll co ll oi da l . T he y a bso r b so me wa v elen g t hs b u t a re n o t la r ge en o u g h t o a bs o rb a l l wa ve l en g t hs of l ig h t . T h is is de pen da n t on t he i n dex of ref ra c t ion of t he b in de r in w hi c h t he y a r e d is pe r se d . F o r exa m p le , a l b u men ha s a d iff e r en t re f ra c t io n to gel a t i n c rea t in g a d if fe r en t c ol o u r. P r in tin g -o u t pa pe rs a f te r f ixin g be co m e ye ll o w/ r ed / b ro wn in co lo u r . Si l ve r pa r ti cl es pa c k cl ose r t oge t h e r a s t he fix er d iss ol ve s un re d u ce d in de x o f ref r a c ti on ha s c o m pl ete l y sil ve r c h lo r id e . T he c ha n g ed , in so d oi n g d ra ma ti ca ll y c ha n gin g t he c ol o u r. Wh en

55 W ar e , M . J . ( 1 9 9 4 ) M e c h an i s m o f I m a g e D e t e r i o r a t i o n i n E a r l y P h o t o g r a ph s - t h e s e n s i t i v i t y t o L i g h t o f W H F T al bo t ' s h al i d e - f i x e d I m a g e s 1 8 3 4 - 1 8 4 4 , S c i e n c e M u s e u m a n d N a t i o n a l M u s e u m o f P h o t o g r a p h y , F i l m & T e l e v i s i o n , B r a d f o r d , L o n d o n . p 1 7

56 R e i l l y , J . M . ( 1 9 8 0 ) T h e A l bu m e n & S a lt e d P a p e r B o o k : T h e H i s t o r y an d pr a c t i c e o f ph o t o g r ap h i c pr i n t i n g , 1 8 4 0 - 1 8 9 5 . , L i g h t I m p r e s s i o n s C o r p o r at i o n . , R o c h e s t e r , U S A . p 6 3

T he Sa l t p ri n t M a n u a l | E xp os in g t he p r in t 5 7

t he p r in t i s d r y i t a p pea rs d a rk e r a n d co l de r d ue t o t he pa r ti cl es pa c k in g cl ose r to ge t he r . 57

A c e rt a in a m o un t o f m oi s t u re i s r e q ui re d f o r sen si t iv it y a n d con t ra s t. O v e r- d r yi n g coa t ed pa p e r be fo re ex p os u re wi l l re d u ce sen si t iv i ty . Exc ess da m pn es s will de st r o y t he n eg a ti ve b y t ra n s fe r rin g t he sil ve r n it r a t e on t he fi l m. M y la r™ s h eet ( 7 5 µ m mi c ron s o r l ess ) b e t we en t h e p a pe r a n d n ega ti ve wi l l a c t a s p r o te c ti on wi t h min i ma l lo ss o f i ma ge s ha r pn es s .

D o n o t a l lo w we t o r da m p fi n ge r s t o t o uc h t he s u rfa ce of t he exp ose d p r in t be fo r e p la cin g i t in t o t h e wa te r ba t hs . T hi s wi l l re s ul t in b ro wn st a i n s.

57 I b i d . p 3

T he Sa l t p ri n t M a n u a l | E xp os in g t he p r in t 5 8

CHAPTER 9

9. PR OC ES S I NG T H E P RI NT

T he w as h , to n i ng , f i xe r a n d f i n a l w as hi ng i n f l u en c e t h e co l o ur a n d t h e l i fe o f t he p ri n t . D u e to t h e a d ve rs e e f f ec t o f t h e f i xer o n t he co lo ur o f t h e s a l t a n d a l b u me n pr i n ts , e a rl y p ri n t ers s e ar c he d fo r w a ys to r e - es t a b lis h d e ns i ty a n d co lo ur . He a t to n i ng w as t h e e ar l ies t me t ho d us e d i n s al t pr i n t i ng . T h is w as us e d b y T a l bo t a n d m a n y o t he r pr i n te rs d ur i ng t h is p e rio d . Ne x t w as s u l p h ur to n i ng us i ng „ o l d h y p o ‟ o r f i xe r . D e co m p o s e d s o d i u m t h io s u l f a te re le as e d s u l p h ur cr e at i ng a b ro w n is h s i lv er s u l p hi d e fro m t he s i lv er i n t h e i m a g e. 58 Co ns e rv a to rs to d ay w o ul d b e ho r r i fi e d a t t h e us e o f s u c h m et ho ds d ue to t he h ig h ris k o f t he i m ag e d et er io r a t in g . D es p i te t h is , m a n y o f t hes e e ar l y s u l p h ur t o n e d p r i n ts h a ve s ur v i ve d , i n c l u d in g t ho s e o f t he a c c l a i me d H i l l a n d A d a ms o n .

to n i ng w as a d a p t e d

fro m

Go l d to n i ng b e c a me co m mo n l y us e d a f t er Fr e n c h ph o t o gr a p he r Gus t a v L eGr a y p u bl i c i s e d i ts us e i n 1 8 5 0 . E a rl y go l d to n i ng w as co m b i ne d w i t h f ix er s k no w n as s e l d ‟o r (to n i ng f i xer b a t h ) b u t t h is w as a l mo s t as d es t r u c t iv e as t he „ o l d h y po ‟ s u l p h ur t o ne r . L a te r, t he i n 1 8 8 6 , p l a t in u m d ev e lo p me n t o f W il l i s ‟s p l a t i no t y pe 59.

M a ke s u re ha n ds a re c lea n a n d d ry be fo r e re m ov in g t h e exp ose d p r in t. Da m pn e ss on fin ge rs o r ha n ds wi ll c r e a te a sta in on t he i m a ge s.

T he la ye r s of a n ex po se d p r in t be fo r e p ro ce ssin g c on s is t of :

t he me ta ll ic sil ve r i ma ge

o

o bin de r ma te r ia l s s u c h a s s ta r c h, g ela t in o r a l b u m en

o un e xp ose d l ig h t -se n si ti ve s il ve r sa l t s (si lve r c hl o ri de , sil ve r n i t ra te , s il v er ci t ra te , s il ve r a lb u m en a te , e tc . , de pen din g on wh i c h c h e mi ca l s ha v e be e n a dd e d)

58 I b i d . p 7 5

59 I b i d . p 8 1

T he Sa l t p ri n t M a n u a l | P ro ce ssi n g t he p rin t 5 9

Al l l ig h t sen s i ti ve sa l ts a re re m o ve d t o s ta b ili se t he p rin t lea v in g t h e me ta ll i c s il ve r i ma g e . S il v er sa l t s a re n o t so l u bl e in wa te r ; t he c h e mi ca l rea c ti on o f s o di u m t h io s ul fa te c rea te s a n o t he r n e w wa te r s ol u bl e c o mp lex . 60

T he g ol d , p la tin u m a n d pa l la di u m ton in g p r oc esse s a re exp en si ve so t ri m off ex ce ss pa pe r a r o un d t he p r in t be fo re pla c in g in t h e wa te r . En s u re t o lea ve a t a l ea s t 1 5 m m bo r de r fo r ha n din g a n d f ra m in g .

P R E- W AS H

Pla ce p rin t in wa r m wa t er , 1 8 to 2 0˚ C f o r on e min u t e wi t h con s ta n t a gi ta t ion . Cha n ge wa te r un t il t he wh i t e c lo u d in g of c hl o ri de i on s s u b si des . T h is ta kes a bo u t 1 0 m in u te s. Pla c e t he p rin t s in a 1 % so l u ti on of s o di u m c hl o ri de a n d a gi ta t e fo r 1 m in u te . 61 T hi s a ss is ts in re m ov in g un e xp ose d si lv e r c h lo r id e a n d si lv e r n i t ra te . T he p r in t fa des t o a d ull b ro wn in t his ba t h b u t wi ll re b ui l d in t he to n e r , fix er a n d d r yin g . T he p r in t re q u ir es a f u r t he r 1 0 min u t es o f f re q ue n tl y c ha n g in g wa t e r .

T he sa l t ba t h a s si s ts in p r ot ec t in g t he lif e a n d a c ti on o f t h e to n in g ba t h a n d p re ven ts s ta in in g in t h e f ixe r . T h e di l u te so di u m c hl o ri de s ol u ti on wi ll n o t d iss ol ve t h e si lve r s a l ts a s t he s o di u m t hi os u lf a te do es . So l u ble s il ve r io n s a re ex ces s sil ve r n i t ra te in sa l t pr in ts . T he se a re o xid is in g a n d ten d t o rea c t wi t h ' h y p o' , u l ti m a tel y c rea tin g si l ve r s ul p h id e . T his c a n ca use a ye ll o w/ b r o wn s ta in . Be fo re fix i n g a sa l t p r in t wi t h t hi os u l p ha te i t is i m po r t a n t t o r e mo ve t he f re e so l ub le s il ve r ion s . S o di u m c hl o ri de doe s t h is b y p re c ip i ta tin g si lve r c hl o ri de wh i c h is n ot oxi d isi n g . I t t hen dis so lve s in t he t hi os u l p ha te fi xe r wit h n o s ul p h id e fo r ma t ion . 62

If t he p rin t i s le f t si t tin g in t he wa s h ba t h d u r in g t he fi rs t f e w m in u te s , t he ex ce ss s il ve r n i t r a te di sp e rsin g in t o t he wa te r c ha n ge s f r o m t h e wh i te cl o u d t o b r o wn , fo r m in g s ta in s on t he p rin t .

D u r in g t he p re - wa s h s t ep , wh i t e cl o ud in g o f t he wa t e r o c c u rs . T his i s t he rea c ti o n b e t ween t he ex ce ss s il ve r n i t ra te le f t in t he pa pe r pl us va ri o us i on s p rese n t in ta p wa te r . T he cl o u din g va rie s de pen din g on t h e a m o un t of un r e d u ce d s il ve r n i t ra te on

60 I b i d . p 8 3

( 1 9 7 5 ) P h o t o g r a p h i c F a c t s a n d F o r m u l a s , A m e r i c an

61 E .J . W al l a n d F .I .J o r d a n P h o t o g r ap i c B o o k P u b l i s h i n g C o . , I n c . , N e w Y o r k U S A . p 2 6 1

T he Sa l t p ri n t M a n u a l | P ro ce ssi n g t he p rin t 6 0

t he pa pe r . A sa l t p rin t on l y re ta in s a bo u t 2 % o f t h e o ri gin a l sil ve r a pp li ed t o a s he et of pa pe r . T he ba la n c e is wa s he d a wa y o r re m ove d in f ixin g. 63 I f t he e xc ess sil ve r n i t ra t e a n d s od i u m n it r a t e a re n o t r e m ove d t h e s il ve r n it r a t e wi l l re ta r d o r p re ven t t on in g f r o m ta k in g p la ce . Bla c k s ta in s m a y a l so re s ul t if ex cess s il ve r n i t ra te a n d s o di u m n i t ra te a re s ti ll p r es en t wh e n t h e p rin t is f i xed .

T O N I N G

in t en si fi e s t he

is s us ce p t ib le

t h e sil ve r pa r t i cle s

No b le me ta l ton in g wi t h g ol d , pla t i n u m a n d pa l la di u m in sepa r a t e ba t hs n o t on l y i ma g e b u t a lso in c re a s es t h e l ife spa n of t he p r in t. Ton in g is es sen ti a l fo r sta b il isin g sa l t a n d a lb u m en p rin ts . T he ma ss of m in us c ul e sil ve r pa r t ic les o n t o t h e pa pe r s u rf a ce des t r u c ti on , oxi d iz i n g in s ul p h u r o us c on d i ti on s of a n o r ma l a t m os p he re . T h e gol d s h iel d s fr o m oxi da t ion by fo r m i n g a co m p o un d t ha t is m o re res is ta n t . Th e to n e rs c rea t e a li g h t sen s i ti ve c hl o ri de a s a b y - p r o d uc t of to n in g . T h is is res o lve d b y t he fi xin g p r oc ess c o m in g a f te r t h e to n in g .

T he t yp e o f b in de r a n d t he p rin t s u r f a ce m u st be c on s id ere d wh e n ton in g . Al b u men re q ui re s a s t r on ge r t on in g s ol u t i on to a ll o w i t t o pe n e t ra t e t he m o re re si lien t s u r fa c e a n d t h e re fo re t he a m o un t o f g ol d c h l or i de in t h e to n e r i s d o u ble d . T he po r o us s u r fa c es o f a r r o wr o o t a n d pla in sa lt e d pa pe r s wi l l t on e fa s te r . T ri m o ff t h e ex ces s bo r de r s of t he p r in t be fo r e to n in g to co n se r ve t he t on i n g so l ut io n s .

Gol d c h lo r i de t on e rs a re rea d y fo r us e wh en t he s ol u ti on be co m es cl ea r . T h i s is kn o wn a s r ip e n in g . W h ile t he g ol d i s ye ll o w i t is in a n in a c t iv e a ci d s ta te . I t ta kes ti m e f o r t he a lk a li n i t y to n e u t r a lis e t he g ol d c h l o ri de b rin g in g i t t o a n a c ti ve s ta te . 64

63 R e i l l y , J . M . ( 1 9 8 0 ) T h e A l bu m e n & S a lt e d P a p e r B o o k : T h e H i s t o r y an d pr a c t i c e o f ph o t o g r ap h i c pr i n t i n g , 1 8 4 0 - 1 8 9 5 . , L i g h t I m p r e s s i o n s C o r p o r at i o n . , R o c h e s t e r , U S A . p 6 6

64 I b i d . p 7 8

T he Sa l t p ri n t M a n u a l | P ro ce ssi n g t he p rin t 6 1

GOLD BORAX TONER 65

1 0 0 0 ml 6 g m 1 2 ml

D is ti lle d wa te r So di u m te t ra b o ra te ( bo ra x ) Gol d c hl o ri de 1% s o lu t ion M et h o d: 1 . Hea t d is t ill e d wa t e r to 3 8° C. 2 . A dd t he s o di u m te t r a bo r a t e . 3 . A dd t he g ol d c hl o ri de . 4 . Rea d y fo r us e wh en t he s ol u t ion i s c lea r .

T he t on e r m u s t si t fo r a pp r ox i ma te ly 1 ho u r bef o re u s e to a ll o w t he a ci di c g o ld to b ec o me a c ti v e t h ro u g h con ta c t wi t h t he a l ka lin e bo ra x. T he t on e r s h o ul d c ha n ge c ol o u r f ro m pa l e ye ll o w t o c lea r a s i t bec o me s a c t ive . T h is ba t h ca n be ke p t b u t a d di t ion a l g ol d m u s t be a d de d a s t h e t on in g ef fe c t s lo ws wi t h usa ge . It m u s t si t a ga in a f t e r a d d i n g m o re g ol d c h lo r i de u n ti l t he s ol u t ion i s c lea r .

SODIUM ACETATE GOLD TONER. 66

1 0 0 0 ml 1 0 g m 1 0 ml

D is ti lle d wa te r So di u m a ce ta t e Gol d c hl o ri de 1% s o lu t ion M et h o d: 1 . Hea t d is t ill e d wa t e r to 3 0° C. 2 . A dd t he s o di u m a ce ta te . 3 . A dd t he g ol d c hl o ri de .

T he so d i u m a ce ta t e ton e r m u s t si t f o r a b o u t 2 4 ho u r s to „ ri pen ‟ bef o re us e 67 to a ll o w t he a c id i c gol d t o b ec o me a c t ive t h ro u g h con ta c t wi t h t he a l ka l in e a ce ta te . T he to n e r s h o ul d

65 J am e s , C . ( 2 0 0 2 ) T h e B o o k o f A l t e r n a t i v e P h o t o g r a p h i c P r o c e s s e s , D e l m a r , N e w Y o r k . p 9 6

66 F ar b e r , R . ( 1 9 9 8 ) H i s t o r i c P h o t o g r a p h i c P r o c e s s e s : A G u i de t o C r e at i n g H a n d m a de P h o t o g r a ph i c I m a g e s , A l l w o r t h P r e s s , N e w Y o r k . p 3 9

67 R e i l l y , J . M . ( 1 9 8 0 ) T h e A l bu m e n & S a lt e d P a pe r B o o k : T h e H i s t o r y an d pr a c t i c e o f ph o t o g r ap h i c pr i n t i n g , 1 8 4 0 - 1 8 9 5 . , L i g h t I m p r e s s i o n s C o r p o r a t i o n . , R o c h e s t e r , U S A . p 7 9

T he Sa l t p ri n t M a n u a l | P ro ce ssi n g t he p rin t 6 2

c ha n g e c ol o u r f ro m pa le ye ll o w to clea r a s i t be co m es a c t ive . T his ba t h ca n b e k ep t b u t a d d it io n a l gol d m u st be a d de d a s t he t on in g ef fe c t s l o ws . 1 to 2 m in u te s in t he ba t h wi l l s h o w c ha n g es , 3 t o 5 m in u te s wi l l s u bs ta n t ia ll y c ha n ge t he p rin t .

THIOCYANATE GOLD TONER1.68

5 0 0 ml 9 g m 3 5 m l

D is ti lle d wa te r So di u m t h io c ya n a te Gol d c hl o ri de 1% s o lu t ion M et h o d: 1 . Hea t d is t ill e d wa t e r to 3 0° C. 2 . A dd t he s o di u m t hi oc ya n a t e . 3 . A dd t he g ol d c hl o ri de . 4 . T his t u rn s re d i m m ed ia tel y a n d is r ea d y fo r use wh en t h e

sol u t ion is c lea r .

T his c rea te s a m uc h co ole r co lo u r a n d sha d o w reg ion s a l m os t i ma g es wil l fi rs t b lea c h ba c k by t he a p pea r b la c k . T he t hi o c ya n a te . A s t he gol d is de po si te d o n t he si lve r pa r t ic le s i t in t en s ifi es . T h io c ya n a te t on e rs c on s u m e m o re go ld t ha n o t he r to n e rs d ue to a g re a te r s u b st i t u ti on o f t he s il ve r b y t he g ol d . 69 I t beg in s to los e t h e t on in g a b il i ty a f t er a n u m be r of p ri n ts . T he t on e d p rin t co l o u r te n d s t o b e a bl ue bla c k .

THIOCYANATE GOLD TONER 270

5 0 0 ml 2. 5 g m 1 g m 2 . 5 g m 1 0 ml

D is ti lle d wa te r So di u m t h io c ya n a te Ta r ta ri c a c i d So di u m c hl o ri de Gol d c hl o ri de 1% s o lu t ion D is ti lle d wa te r t o m a ke 5 0 0 ml

68 I b i d . p 7 9

69 I b i d . p . 7 6

70 C r aw f o r d , W . ( 1 9 7 9 ) K e e pe r s o f t h e L i g h t , M o r g a n & M o r g a n , I n c . , N e w Y o r k , U S A . p 1 5 6

T he Sa l t p ri n t M a n u a l | P ro ce ssi n g t he p rin t 6 3

M et h o d: 1 . Hea t d is t ill e d wa t e r to 3 0° C. 2 . A dd t he s o di u m t hi oc ya n a t e . 3 . A dd ta r ta ri c a ci d . 4 . A dd s o di u m c hl o ri d e . 5 . A dd t he g ol d c hl o ri de . 5 . T his t u rn s re d i m m e dia t el y . 6 . A dd wa t e r t o m a ke 5 0 0 ml . 7 . I t is rea d y f o r u se when t he s ol u t ion i s cle a r.

L ik e t h e t hi oc ya n a t e go ld t on e r No 1 i t wi ll on l y l a s t t he da y t ha t i t is ma de . I t ca n n ot be re us ed . T he t on e d p r in t c o lo u r ten ds t o be a wa r m er bla c k t ha n t hi oc ya n a te go ld t on e r N o 1 . T his t hi o c ya n a te t on e r fo r m u la i s in cl u de d a s is less gol d c hl o ri de in t he s ol u ti on t he re fo re m o re e con o mi ca l . Pla t in u m T on e r 71

1 0 0 0 m l 2 . 5 m l 2 . 5 g m

D is ti lle d wa te r a t 3 0° C Po ta ssi u m c h lo r op la tin i te 2 0% Ci t ri c a c i d M et h o d: 1 . Hea t d is t ill e d wa t e r to 3 0° C . 2 . A dd t he Po ta ssi u m c hl o r op la tin i te . 3 . A dd t he ci t r ic a ci d . 4 . T he t on e r i s r ea dy f o r u se wh en co ole d to 2 0 ° C.

T his cr ea tes a b r o wn b la ck ton e . Do n o t ov e r- t on e a s t he r e is a ri s k of dev el op in g ye ll o w h ig h li g h ts . I m p u ri t ies ma y d es t r oy t he b a t h ‟s ton in g a b il i ty t he re fo r e be s u re t he p re - wa s h re m ov e s a ll un re d u ce d s il ve r n i t ra t e a n d o t h e r i on s f ro m t he p rin t .

71 J am e s , C . ( 2 0 0 2 ) T h e B o o k o f A l t e r n a t i v e P h o t o g r a p h i c P r o c e s s e s , D e l m a r , N e w Y o r k . p 9 9

T he Sa l t p ri n t M a n u a l | P ro ce ssi n g t he p rin t 6 4

PALLADIUM TONER72

1 0 0 0 ml 2 . 5 ml 2 . 5 g m 2 . 5 g m

D is ti lle d wa te r So di u m c hl o ro pa lla di te 1 5 % so l u ti on Ci t ri c a c i d So di u m c hl o ri de M et h o d: 1 . Hea t d is t ill e d wa t e r to 3 0° C. 2 . A dd t he S o di u m c hl o ro pa l la di te . 3 . A dd t he ci t r ic a ci d , di sso lv e . 4 . A dd t he S o di u m c hl o ri de . 5 . U se wh en c oo le d to 2 0 ° C . I t c rea tes a b r o wn bla c k to n e, b u t ca r e n ee ds to be ta k en n o t to ov e r t on e a s t he r e is a r is k o f de ve lo pin g y ell o w hi g hl ig h ts . I m p u ri t ies ma y de st r o y t he b a t hs to n in g a bi li t y . T he wa s h m u st clea r t he p r in t of un -r ea c te d s il ve r n i t ra te . T hi s c rea t es a gr e y b r o wn b la c k t o n e.

N B: T he p la tin u m a n d pa lla d i u m ton e r s do n o t gi ve t he m os t a gr eea bl e c ol o u rs on c e r ta in pa pe r s a n d fo r m u la s . Al b u men ma y be co m e q u i te yel lo w. S pli t t on in g wi t h go l d t on er s fol lo we d b y p la tin u m o r pa l la di u m g iv es t he p rin t s a n ex t ra de p t h of co lo u r . O n ly a fe w s ec on ds ma y b e r eq u i re d in t he pla t in u m o r pa l la d i u m . Te s tin g is s t r o n gl y s ug ges t ed be f o re pla c in g t he p r in t in to t he t on e rs .

N B: W hen s pl i t ton in g , go l d t on e r s m us t be us ed be fo r e t he a ci d ic p la tin u m o r pa lla di u m ton e rs . T he a c id wi ll sl o w o r a c t ua l l y s to p t he a c ti vi t y o f t he a l ka lin e gol d ton e rs . W a s h fo r a t le a s t 2 m in u tes b et we en ea c h t on in g sol u t ion .

T he t on in g b a t h s h o ul d b e a t 1 8° C t o 2 2 °C . Pl a c e p rin t in ba t h fo r 1 up t o 1 0 min u te s wi t h con st a n t a gi ta ti on . 2 t o 5 min u te s wi l l gi ve y o u p r o te c ti on wi t h so m e c ol o u r c ha n ge. F o r ea c h o f t he t on e rs y o u p la n to u se , p r in t fi ve st ep e d ge s . Pla ce a l l in t he ton e r a n d re m o ve on e a t 2 m in u tes , t he n ex t a t 4 m in u te s, 6 m in u tes , a n d 1 0 m in u tes . I f t he te s t a re c o r re c tl y p r oc e sse d t he t on e d s te p we dge s wi ll a c t a s a pe r ma n en t r ec o r d a n d us ef u l g ui de f o r f u t u re to n in g .

72 F ar b e r , R . ( 1 9 9 8 ) H i s t o r i c P h o t o g r a ph i c P r o c e s s e s : A G u i de t o C r e a t i n g H a n d m a de P h o t o g r a ph i c I m a g e s , A l l w o r t h P r e s s , N e w Y o r k . p 4 1

T he Sa l t p ri n t M a n u a l | P ro ce ssi n g t he p rin t 6 5

En s u re t he re is a de q ua te b u t lo w in ca n des cen t lig h t in g to vie w t he to n in g p r oc ess . Ab o u t 2 5 wa t t a t 1 . 0 m d is ta n ce is fi n e. Co m pa rin g a d u p li ca te p r in t in t he wa s h wa te r bes id e t h e to n in g p r in t hel ps see s h if ts in t h e c o lo u r . Ta ke in to a c c o un t t he c ol o u r d if fe ren ce wh e n t he p rin t is d rie d . Ex pe r ien c e is t he bes t g u i de . Pe n ci lle d ton in g de ta ils on t he ba c k of t he p rin t wi ll p r ov i de i n va l ua b le f u t u re re fe ren ce . If t he n o r ma l ti m e f o r c ol o u r c ha n ge ha s do u b le d , i t mea n s t he ton in g ba t h is b e c o min g d ep le te d. I t i s in a c ti ve wh e n i t i s ex ha us t ed .

Kee p t h e ton in g ba t h a n d fix e r b a t h a p a r t . Des ign a t e a t ra y f o r gol d t on in g on l y . E v en a m ic r os c op i c a m o un t o f fix e r wi ll sp oi l t he ex pe n si ve g ol d t on e r a n d t he p rin t . 73

W a s h t he p r in t a f te r t on in g fo r a t l ea s t 4 m in u te s in ta p wa te r . Cha n g e t h e wa te r t ra y a t lea s t 3 ti me s d u r in g t h is pe r io d to en s u re t he to n in g sol u t ion d oes n o t con ta m in a te t h e fi xer . Con ta m in a te d fi xe r wi l l eff ec t t he s ta b i li t y of t he p rin t .

N B: T he t hi o cy a n a te ton e r ca n c ha n ge t he fi xe r t o a s ul p h u r o us sta t e . E x t ra wa s h in g a f te r ton in g is re q ui r e d be fo re p la c i n g in t he f ixe r . C ha n ge t he f ix in g b a t h m o re fre q uen t l y wh en u sin g t hi s t on e r .

T he s iz e, s ha pe a n d dis ta n ce b et ween t he sil ve r pa r ti c les a n d t he r ef ra c ti on of m ed i u m t he y a re d i s pe rs ed in wil l i n fl u en ce t he p r in t co lo u r . T h e g ol d t on in g m o dif ies t h e i m a ge c ol o u r b y c ha n g in g t he si ze a n d s ha pe of t he sil ve r pa r ti c les b y re pl a c in g s il ve r a t o ms wi t h g ol d a t o ms . T hi s en la rg e men t ma ke s t h e i ma g e lo ok co ol e r a n d mo r e n eu t ra l in t on e . I f gol d c hl o ri de ( I I I ) wa s us ed fo r t on i n g , t h ree a t o ms of si lv e r wo ul d be re pl a c ed b y on e a t o m o f g ol d . 74 The i ma g e wo u ld t hen a p pea r r e dd is h in co lo u r a n d fla t in a p pea ra n ce . 75 By ma kin g t he ton e r a l ka l in e t hi s r e d uc es t he s ta te o f g ol d ( I I I ) t o g ol d

73 R e i l l y , J . M . ( 1 9 8 0 ) T h e A l bu m e n & S a lt e d P a pe r B o o k : T h e H i s t o r y an d pr a c t i c e o f ph o t o g r ap h i c pr i n t i n g , 1 8 4 0 - 1 8 9 5 . , L i g h t I m p r e s s i o n s C o r p o r a t i o n . , R o c h e s t e r , U S A . p 7 9

74 W ar e , M . J . ( 2 0 0 6 .) G o ld i n P h o t o g r a ph y ., f f o t o f f i l m p u b l i s h i n g , B r i g h t o n , U K . p 1 1 0

75 R e i l l y , J . M . ( 1 9 8 0 ) T h e A l bu m e n & S a l t e d P a p e r B o o k : T h e H i s t o r y a n d pr a c t i c e o f ph o t o g r ap h i c pr i n t i n g , 1 8 4 0 - 1 8 9 5 ., L i g h t I m p r e s s i o n s C o r p o r a t i o n . , R o c h e s t e r , U S A . p 7 9

T he Sa l t p ri n t M a n u a l | P ro ce ssi n g t he p rin t 6 6

( I) . T he a t o ms o f g ol d t hen re pla ce o n e o f t he si lve r , 76 t h us re s ul tin g in a c oo le r c ol o u r a n d t h e t on a l ra n ge in ta c t . 77

Ch ec k t he p H o f t h e t on e r to en s u re c on si s ten c y a n d t h a t i t re ma in s a lk a li n e . I f t he ton e r is to o a l ka lin e i t wi l l :

o L ose i t s t on in g ca pa ci t y mo r e ra p id l y.

o Ton e m u c h fa s te r.

o Po ssi b l y s to p ton in g if to o ex t re m e .

o P ro d u ce bl ue g r e y c ol o u rs wh i c h a re n o t a s plea sa n t.

S E L E N I U M T O N I N G

T his is a n un sa t is fa c t o r y ton e r f o r sa l t o r a l b u m en p rin t s ei t he r be fo re o r a f t er fi xin g . T h is is d ue to t h e tin y pa r t i cle ‟s lo w a bs o rb in g po w er ; t he si lv er s ele n id e a n d s il ve r s u lfi de wh i c h be co m e s e m i - t ra n s pa ren t t he i ma ge a p pea r s t o h a ve been bl ea c h e d. 78

H E A T T O N I N G

T his is c a r rie d o u t a ft e r t h e p r in t ha s been p r oc ess e d , wa sh ed a n d d rie d . He a tin g to n in g ca n be a c hi e ve d b y us in g a h o t ir on wi t h p a p e r b e t ween t he p ri n t a n d t h e ir on . T h e te m pe ra t u re ca n be se t on s il k o r co t t on . A d r y m o un tin g hea t p res s ca p t u res t h e mo is t u re a s we ll a s a p p ly in g h ea t. A g re a te r to n in g eff ec t i s fo u n d usin g t h e d r y m o un tin g p re ss , t he p rin t co lo u r c oo ls c on s i de ra bl y . In a n s we r t o m y q ue r y on t he co lo u r c ha n g e M i ke W a r e s ug ges t s “t h e p a r t i cle s m a y be cl u m p in g to ge t he r o r i t is l i k el y t o b e a lt e rin g t he ex t e n t o f su l p hi din g o n t he su r fa ce of t he si lv er n a n - pa r ti cl es . T he se co lo u r s wil l b e ve r y sen si t ive t o t he s t a te o f t he s u rfa ce . ”

T H E F I X E R

i n i t i al l y

„s t a b i lis e d ‟ h is p r i nt s w it h s tro ng s o d i u m T a l bo t c h lo r i d e s o l u t io ns . T h is d i d no t r e mo v e th e u ne x po s e d s il ve r

76 W ar e , M . J . ( 2 0 0 6 . ) G o ld i n P h o t o g r a p h y . , f f o t o f f i l m p u b l i s h i n g , B r i g h t o n , U K . p 1 1 0

77 R e i l l y , J . M . ( 1 9 8 0 ) T h e A l bu m e n & S a lt e d P a p e r B o o k : T h e H i s t o r y an d pr a c t i c e o f ph o t o g r ap h i c pr i n t i n g , 1 8 4 0 - 1 8 9 5 . , L i g h t I m p r e s s i o n s C o r p o r at i o n . , R o c h e s t e r , U S A . p 7 8

T he Sa l t p ri n t M a n u a l | P ro ce ssi n g t he p rin t 6 7

c h lo r i d e b u t c h a ng e d i t in to a les s s ens i t i ve fo r m . 79 So d i um t h io s ul f a t e w as d is co ve r e d by S ir Jo h n He rs c he l i n 1 8 1 9 , h e fo u n d i t w o ul d d is s o lv e s i l ve r s a l t s . Fo l lo w i ng He rs he l ‟s s ug ges t io n in 1 8 3 9 T a l bo t s u c ces s f u l l y c le a re d s i l ve r c hlo ri d e fro m h is pr i n ts t h u s s t a bi l is i ng t he m p er m a ne n t l y . S ti l l t o d a y s o d i u m a n d a m mo n i u m t hi o s u l f a t e ar e us e d as f i xe rs i n bo t h p ri n t i ng a n d de ve lo p i ng - o u t p ro ces s es .

T he p u r po se of f ix in g is to r e mo ve t he si lv e r c hl o ri de a n d ot h e r lig h t -se n si t iv e s u bs ta n ce s wh i c h ma y b e p res en t. T h e p H of t h e ba t h is i m p o r ta n t . A dd in g s od i u m ca r b on a te ma kes t h e sol u t ion a lk a li n e t h us re d u cin g t h e bl ea c h in g e ffe c t o f t he fixe r . T h is a l so s t op s a c id s f ro m de co m p os in g t he s od iu m t hi os u lfa t e a n d l i be ra ti n g s u l p h u r. An a ci d fix e r ba t h s ca us e s bl ea c h in g i n t he h ig hl ig h t s a n d mi d - to n es by a t ta c kin g t he fin e s il ve r me ta ll ic pa r ti cle s . 80 T he rea son c o m m er c ia l f ix er s a re n o t s ui ta bl e fo r sa l t p r in t in g.

FIXER

7 5 0 ml 1 5 0 g m 2. 5 g m 1 0 0 0 ml

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fixe r

t hi s

i s un s t a bl e wh en d iss ol ve d

I t

Wa t e r So di u m t h ios u lf a t e So di u m ca r bon a t e Wa t e r t o m a ke M et h o d: 1 . Hea t t he 7 5 0 m l o f wa t er t o 3 0 °C . 2 . A dd t he s o di u m t hi os ul fa te . 3 . A dd t he s o di u m ca r bon a t e. 4 . A dd wa t e r t o m a ke 1 0 0 0 m l. NB: M a ke t o mi n i m ise de co m p os i ti on . S o d iu m t h io s ulf a te in i ts d r y fo r m i s r ela t i vel y sta b le . in wa te r , s l o wl y de co m p os in g to s o d iu m s ul p hi t e a n d e l em en ta l s u l p h u r. 81 U sa ge : 1 . M a in ta in t he te m pe ra t u re o f t h e fix in g sol u ti on to b e t wee n

1 8 °C to 2 0° C.

79 R e i l l y , J . M . ( 1 9 8 0 ) T h e A l bu m e n & S a lt e d P a pe r B o o k : T h e H i s t o r y an d pr a c t i c e o f ph o t o g r ap h i c pr i n t i n g , 1 8 4 0 - 1 8 9 5 . , L i g h t I m p r e s s i o n s C o r p o r a t i o n . , R o c h e s t e r , U S A . p 8 3

80 I b i d . p 8 4

81 I b i d . p 8 3

T he Sa l t p ri n t M a n u a l | P ro ce ssi n g t he p rin t 6 8

2 . U se t wo s u c ces si ve fixin g ba t h s . Ag i t a te f o r 4 min u te s in

ea c h ba t h . T he 2 ba t hs he l p t o m a xi m is e pe r ma n en c e .

3 . D ra in fo r a t le a s t 5 sec on ds be t wee n ba t hs .

T he t wo ba t hs a r e es sen tia l a s t hi os ul fa te io n s m u s t be p res en t in e xc ess o r in s ol u b le c o m plex e s a re f o r me d wh i c h a re on l y s ol u ble in f res h t hi os u lfa te :

1 . In t he fi r s t ba t h si l ve r - t h io s ulf a t e c o m pl exes f o r m a n d

m os tl y di sso lv e .

2 . In t he se co n d ba t h a n y re si d ua l in so l u bl e c o m pl exes a re

re m ov e d .

P ro lon ge d f ix in g c a n da ma ge t he p r in t a s t he t h i os ul fa t e pen e t ra t es t he p a p e r f ib r es a n d be c o m es d iff i c ul t to re m o ve. 82 T he ex t ra si lve r p re sen t in sa l te d p a pe rs ra pi d ly ex h a us t s fix in g ba t hs so a m a xi m u m o f t we n t y 8 x1 0 p rin ts i s a d vi sa bl e in e a c h l i t re o f fi xe r .

TES T TO S EE IF F IX E R I S EX H AU S TE D

KODAK FIXER TEST SOLUTION FT1

1 0 0 ml 1 9 g m

Wa t e r Po ta ssi u m io d id e M et h o d: 1 . Hea t wa te r to 3 8 °C . 2 . A dd po ta ssi u m io d i de . 3 . I t is rea d y f o r u se when di sso lv e d a n d c oo le d t o 2 0 °C . U sa ge : 1 . A dd 5 d ro ps o f tes t sol u t ion t o 5 d ro ps of f ixin g ba t h . 2 . A dd 5 d ro ps o f wa te r . 3 . T he fi xe r is ex ha u s te d i f a wh i tis h ye l lo w p re ci pi ta t e fo r ms

i m me dia t el y . Re pla c e f ixe r ba t h .

82 I b i d . p 8 4

T he Sa l t p ri n t M a n u a l | P ro ce ssi n g t he p rin t 6 9

W AS H I N G T H E P R I N T

A r esi d u e of t hi os ul fa te wi ll e ven t ua ll y d ec o m po s e a n d deg r a d e t he p rin ts a n d wi t h hig h l ev el s , s ul fi din g of t he s ilv e r i ma ge wi l l o cc u r ov er t i me . 83

Wa s h bef o re h y p o cle a rin g t rea t men t . W a s h t he p r in ts f o r 4 m in u tes , c ha n gin g t he wa t er ba t h a t lea st t wi c e be fo r e t r ea t in g wi t h a h y po c lea r in g a gen t. T h is wa s h re m ov es a la rg e po r ti on of t h e fix e r a n d a vo id s ove r lo a d in g t he me c ha n is m of h y po re m ov a l . 84

T H E C L E A R I N G A G E N T

t ha n

T he un p r o te c te d wa te r c ol o u r pa pe r ba se of sa l t ed pa pe r a n d a lb u m en pr in ts a llo ws a g re a te r a bs o r pt io n of so di u m t hi os u lfa t e c o m me r cia ll y p r od u ce d d eve lo p i n g -o u t pa pe rs . A c lea r in g a gen t is ess en tia l a s wa te r i s n o t eff ec ti ve a t re m o vin g e ven l o w l eve ls of so d i u m t h io s ul fa te. A wa sh in g a id kn o wn a s h yp o cle a rin g a gen t is t h ere fo r e n ec essa r y

A wa s hin g a i d , m o r e co m m on l y kn o w a s h y po clea r in g a g en t , con sis t s of 1 % s ol u ti on o f so d i u m s ul p hi t e .

CLEARING AGENT

1 0 0 0 ml 1 0 g m

Wa t e r So di u m s ul p hi te M et h o d: 1 . Hea t wa te r to 3 0 °C . 2 . A dd s o di u m s u l p hi t e. U se wh en d is so lve d a n d te m pe ra t u re i s a p p rox i ma te l y 2 0 °C . To U se : Pla ce p r in ts in ba t h a n d a g it a t e f o r 4 m in ut es . D is ca rd e d a f te r ma x i m u m of 2 0 8x 1 0 p rin ts . T h e re is a p p rox i ma te l y t h e sa me ra te of ex ha u s ti on a s s o di u m t hi os u lfa t e f ixe r .

83 L a v e d r i n e , B . ( 2 0 0 3 ) A G u i d e t o t h e P r e v e n t at i v e C o n s e r v a t i o n o f P h o t o g r a p h i c C o l le c t i o n s , T h e G e t t y C o n s e r v at i o n I n s t i t u t e , L o s A n g e l e s U S A . p 2 2 0

T he Sa l t p ri n t M a n u a l | P ro ce ssi n g t he p rin t 7 0

Wa s hin g a l on e wi ll n o t clea r o u t t he so di u m t h io s ul fa te . To re d u ce t he ri sk of p rin ts de co m p os i n g t he u se o f a h y po cle a rin g a ge n t is e ssen tia l . I t a s sis t s in t he m o re c o m p le te re m ov a l of sil ve r - t hi os u lfa t e c o m pl ex es . T he h y po c lea rin g a gen t r ep la ces t he t hi os u lfa t e ion s wi t h sul fa te i on s wh i c h a re ea si ly e li m in a te d in t he wa s h .

T H E F I N A L W AS H

In s u ff ic ien t wa s hin g is s ti ll t he ma in c a us e of de te r io ra t io n of a ll p h o t og ra p hs . Fa c to r s fo r c ri ti ca l wa sh in g :

o Ag i ta ti on .

o Wa t e r r ep la ce men t d u rin g t h e wa s h .

o Wa t e r ha r dn ess .

o Te m pe ra t u re a bo ve 2 0 °C .

o Ti me i t ta ke s f o r t h e fi xe r to d if f use o u t of t he pa p er

in t o t he wa te r . 85

So di u m t hi os u lfa te is h ea v ie r t ha n wa te r . I t sin k s a n d n ee d s to be re m ov ed . W a s he r s wi t h a t o p ove r fl o w wi ll n ot be su ff ic ien t , 86 t h e ref o r e a g i ta ti on is re q u i r ed .

Be pe da n t ic a b o u t wa s hin g yo u r ha n ds t h o ro u g hl y . H a n ds con ta m in a te d wi t h c he m i ca l res i d ue s ta i n p rin ts .

De pen d in g o n t he t hi c kn e ss o f t h e p a pe r , t h e p r in ts s h o ul d re ce ive a t lea s t a 3 0 - m in u te wa s h . H ea vi e r p a p e rs a n d m o re den s el y coa t ed pa pe rs s uc h a s a lb u men wi ll re q u i re l on ge r wa s h t i mes t ha n pla in sa l te d p rin ts .

Con s ta n t r un n in g wa te r is n o t n e ces sa r y t o a c hi eve a n a r c h iva l wa s h. Con se r ve wa te r a n d en e rg y b y u s in g a t wo t ra y s ys te m of wa s h in g . Pla ce a ma x i m u m o f 6 p r in t s in a t ra y o f wa r m wa t er 1 5° C to 1 8°C . T he t ra y n ee ds t o be a t l ea s t do u b le t he si ze o f t he p r in ts . Ag i ta te t he t ra y fo r 5 m in u te s . Ge n tl y sh u ff l e t h e p r in ts s o ea c h ha s mo ve m e n t o f wa t e r a c r oss t he su r fa ce . D ra in ea c h p ri n t a n d pla ce o n e b y on e in t h e c lea n t ra y o f wa t e r. Ag i ta te a n d s h uf fle a ga i n fo r 5 m in u tes . Re pea t

84 R e i l l y , J . M . ( 1 9 8 0 ) T h e A l bu m e n & S a lt e d P a p e r B o o k : T h e H i s t o r y an d pr a c t i c e o f ph o t o g r ap h i c pr i n t i n g , 1 8 4 0 - 1 8 9 5 . , L i g h t I m p r e s s i o n s C o r p o r at i o n . , R o c h e s t e r , U S A . p 8 9

85 L a v e d r i n e , B . ( 2 0 0 3 ) A G u i d e t o t h e P r e v e n t a t i v e C o n s e r v a t i o n o f P h o t o g r a p h i c C o l l e c t i o n s , T h e G e t t y C o n s e r v at i o n I n s t i t u t e , L o s A n g e l e s U S A . p 2 2 0

86 E p h r au m s , E . ( 1 9 9 5 ) C r e at i v e E le m e n t s , 2 1 s t C e n t u r y P u b l i s h i n g L t d , L o n d o n G r e at B r i t a i n . p 1 4 5

T he Sa l t p ri n t M a n u a l | P ro ce ssi n g t he p rin t 7 1

t hi s p r o cess fo r a t lea s t 6 to 1 2 c h a n g es of wa t e r. 87 Af te r t he fi rs t t wo c ha n ges t h e wa te r ca n be use d sa fel y in t he g a r d e n .

If i ma ge s a re t es t p r in t s a 5 m in u te wa s h i s a de q ua te .

TES TS FO R R ES I DU A L SO D IU M TH IO SU L F AT E

KODAK HYPO TEST SOLUTION HT1A

1 8 0 ml 0 . 3 g m 0 . 6 g m 2 5 0 ml

D is ti lle d wa te r Po ta ssi u m pe r m a n g a n a te So di u m h y d ro xi de D is ti lle d wa te r t o m a ke M et h o d: 1 . Hea t 1 8 0 m l wa te r t o 2 0 °C . 2 . A dd po ta ssi u m pe r ma n ga n a te , d iss ol ve . 3 . A dd t he S o di u m h y d r oxi de . 4 . A dd wa t e r t o m a ke 2 5 0 ml . T o U se : 1 . D il u te 1 ml o f t he s ol u ti on in 1 2 5 ml of wa te r . 2 . Po u r 1 5 ml of t he pr epa re d s ol u t ion in t o a g la s s c on ta in e r. 3 . Ta ke t h e p r in t f ro m t he wa s h t ra y . 4 . Al lo w t o d r ip f o r 3 0 se c on d s in to t he s o lu t ion . T he res i d ua l fix e r wil l c h a n ge t h e sol u t ion f ro m p u r pl e t o o ra n ge in 3 0 se co n ds . I t b ec o me s c ol o u rle ss a ga in in on e m in u te .

T he f oll o wi n g f o r m u la t es ts i f t h e wa s h in g p ro ce d u r e is a de q ua te l y re m ov in g t h e s od i u m t hi os ul fa te . If t h e re i s m o re t ha n 0 . 0 0 9g / m 2 , b r o wn s ta in in g wi ll oc c u r . T h e t hi os u lfa te a n d t he de co m p os it io n by - p ro d u c ts p r o d u ce si lv e r s ul p h id e , fo r me d by t he rea c ti on wi t h t he si lv e r n it ra te . 88 The i n t en s it y of t he s ta i n in di ca te s t he a m o un t of re si d ua l fixe r in t h e p r i n t .

87 A d am s , A . ( 1 9 9 4 ) T h e P r i n t , L i t t l e , B r o w n a n d C o m p a n y , T o r o n t o C a n ad a . p 1 3 5

88 L a v e d r i n e , B . ( 2 0 0 3 ) A G u i d e t o t h e P r e v e n t at i v e C o n s e r v a t i o n o f P h o t o g r a p h i c C o l le c t i o n s , T h e G e t t y C o n s e r v at i o n I n s t i t u t e , L o s A n g e l e s U S A . p 2 2 4

T he Sa l t p ri n t M a n u a l | P ro ce ssi n g t he p rin t 7 2

KODAK HYPO TEST HT-2

7 5 0 ml 1 2 5 ml 7 . 5 g m 1 0 0 0 ml

D is ti lle d wa te r 2 8 % a ce t i c a c id Sil ve r n i t ra t e D is ti lle d wa te r t o m a ke M et h o d: 1 . Hea t t he 7 5 0 m l wa t er to 2 0 °C . 2 . A dd 2 8 % a ce t i c a c id . 3 . A dd t he S il ve r n i t ra te . 4 . A dd wa t e r t o m a ke 1 0 0 0 ml . T o U se : T his me t h o d te s ts t he wh o le p rin t a n d is ti m e con s u min g , b u t in d i ca te s t he wa s hi n g t i me re q u i re d. M a ke 6 s ma l l p r in ts a n d on t he ba ck of ea c h wr i te :

1 5 min s wa s h 2 0 min s wa s h 3 0 min s wa s h 4 0 min s wa s h 6 0 min s wa s h Ref e ren ce p r in t (n o t to be tes te d in t he a bo ve s ol u t ion )

a ) b ) c) d) e) f)

1 . P ro ce ss n o r ma ll y , i n cl u d in g t he h yp o c lea r. 2 . U se t h e 2 t ra y wa s h sy st e m . 3. Agitating and changing water each 5 minutes for the first 15 minutes. 4 . A t 1 5 m in u tes of wa sh t a ke o ut t he p rin t ma r ke d 1 5 m in . In s u b d ue d li g h t p la ce d in t he si lv e r n i t ra te s ol u t ion . 5 . 6 . Ag i ta te f or 4 m in u te s. 7 . Re m ove a n d pla ce i n a t ra y o f 5 % s o d iu m c h lo r i de , a gi ta t e

fo r 4 m in u te s .

8 . Ch ec k f o r s ta i n s . ( T o ke ep s a m ple s , re fi x a n d wa s h . ) 89 9 . Con tin u e t h is p ro ce d u re wi t h a ll t he te st p rin t s EX CE PT t h e re fe ren ce p ri n t , wa sh in g , a gi ta tin g a n d c ha n g in g wa t e r u p to t he ti m e m a r ke d on t he ba ck of t he p rin t . Wh en t h e p r in t s h o ws n o s ign o f s ta i n in g i t t he r ef o re h a s no so di u m t h io s ul fa te p res en t t h us i n d i ca tin g yo u r id ea l wa s h ti m e. A ll o w a f u r t he r 1 0 min s of wa sh ti me to e n s u re y o u r p rin t s wi l l en d u re t he te st of ti m e.

89 A d am s , A . ( 1 9 9 4 ) T h e P r i n t , L i t t l e , B r o w n a n d C o m p a n y , T o r o n t o C a n a d a . p 2 0 3

T he Sa l t p ri n t M a n u a l | P ro ce ssi n g t he p rin t 7 3

M a ke s u r e ha n d s a r e s c r u p ul o us l y cl ea n b ef o re re m ov in g t he p rin t f r o m t he f in a l wa s h . D r yin g ra c k o r pe gs f o r h a n gi n g m u st be f r ee f r o m c on ta min a t ion . S ta in s a t t he l a s t st a ge o f t he p ro ce ss ca n be de va s ta ti n g . T he wo r k , t i me a n d c os ts in v ol ve d a r e a ll wa s te d , es pe cia ll y i f t h e p rin t ha s been go l d o r pl a tin u m ton e d.

D R Y I N G

1 . Ai r d ry b y ha n g in g wi t h pe gs on a d r yi n g lin e in a

p ro t ec te d en vi r on m en t .

2 . Pla ce on d r yin g ra c k s fa ce - u p a f te r a l lo wi n g t he p rin ts

to d ri p o ve r t he da r k ro o m s in k.

3 . Hea t d r y us in g a ha i r d r y e r.

T he p rin t wi ll c ha n ge co lo u r a s i t d r ie s , be c o min g co ole r a n d da r ke r . T he sil ve r p a r ti c les a re a bs o r bi n g m o re vis i ble l ig h t a s t he y pa c k cl ose r t og et he r .

T he Sa l t p ri n t M a n u a l | P ro ce ssi n g t he p rin t 7 4

ST O R AG E A N D FR A MI NG

10.

CHAPTER 10

c o r re c t p r o c essin g me t h od s

T he s ma ll pa r ti cl e s of s il ve r in p r i n ti n g - o u t pa p e rs c rea t e gr ea t d et a il b u t i t is t hei r ve r y min us c ule si ze wh i c h ma kes I ma ge d eg ra da ti on by va ri o us c he m ica l t he m v uln e r a b le . co m p o un ds in t he a t m os p he re o r i n a d eq ua te p ro ce ssin g ma y ca use oxi da t ion . T hi s ca n a p pea r a s fa d in g , s ta in in g a n d di sc ol o u ra ti on . 90 U sin g of con se rv a t io n s to ra ge , f ra min g me t ho ds a n d ma te r ia ls wi l l a ssi st in p ro te c ti n g t he sa l t a n d a lb u men p rin ts f o r m a n y yea r s.

S TO R AG E

f o r

U n f ra me d i ma g es t ha t re q ui re l on g t er m s t o ra ge s h o ul d be pla ce d i n a r c h iva l m u se u m box es to be ke p t c o ol , da r k a n d d r y. So la n de r box es a re p ro d u ce d spe c ifi ca ll y t hi s p u r pos e . H u m i di t y con t r ol i s t he mo s t i mp o r ta n t fa c to r in t he st o ra g e a r ea . Re si d u a l c he m i ca l s in t he pa pe r a n d e m ul si on a re a ffe c te d b y hi g h mo is t u re c on ten t en c o u ra gin g m o ul d g r o wt h . 91 Hig h te m pe ra t u re s in c re a se t he r ea c ti on o f t he c he m ica l s of t he p r in t. A ri ses i n t e m pe ra t u re of 1 0° C ca n d o u ble t h e ra t e of c h e mi ca l r ea c t io n .

Po l yp r o p ylen e a n d M yl a r™ a re c o m ple t el y in e r t a n d o ffe r p ro t ec t ion f or ha n dl in g a n d s to r a ge of n ega t iv es a n d p rin t s .

Con s e rva t ion boa r d s p ro m o te t he l on g e vi t y o f t he p rin t , a s do t he f ol lo win g m e t ho ds a n d m a te ria ls us ed to con ta in a n d h ol d t he p rin t .

t he re a r e n o c he m i ca l

i m p u ri t ies

in

1 . 1 0 0 % c o t ton ra g m a t t is t he p u re s t fo r m o f c el l ul ose . 92 En s u re t he m o un tin g ma te ria ls . M y la r c o rn e rs h o ld t he i m a ge in pla ce , a l lo wi n g p rin t re m ov a l wi t h o u t d a ma ge .

90 L a v e d r i n e , B . ( 2 0 0 3 ) A G u i d e t o t h e P r e v e n t a t i v e C o n s e r v a t i o n o f P h o t o g r a p h i c C o l le c t i o n s , T h e G e t t y C o n s e r v at i o n I n s t i t u t e , L o s A n g e l e s U S A . p 6

91 Ke e f e , L au r e n c e E . I n c h , D e n n i s 1 9 9 0 , T h e L i fe o f a P h o t o g r a ph , A r c h i v a l P r o c e s s i n g M at t i n g F r a m i n g S t o r a g e , 2 n d e d i t i o n F o c a l P r e s s , U S A . p 2 4 7

92 L am b , A . R . ( 1 9 9 9 ) F r a m i n g P h o t o g r a p h y , C o l u m b a P u b l i s h i n g , O h i o , U S A . p 5 1

T he Sa l t p ri n t M a n u a l | S to ra ge a n d F r a m in g 7 5

2 . Hin ge d m a t bo a rd s c a n b e o pen e d f o r re m ov a l o f p r in t a n d to in sp ec t fo r da ma g e s uc h a s f a din g, in se c ts o r m o ul d .

3 . M a t ts s e pa ra te t he p rin t f r o m t he g la ss in t he f ra m e.

4 . T he s ta n da r d is a ti on of m a t si ze s a l lo ws ea s ie r s t o ra g e

un de r con t r ol le d c o n di t ion s. 93

5 . T he s ign a t u re o f t he a r t is t / p ho t og ra p he r m u s t be on t he p r in t, n o t t he m a t bo a r d . T his ca n b e on t he re ve r se of t he p r in t , e n s u r e it i s o u ts i de t h e i ma ge a rea o r on t he fr on t bel o w t h e i ma ge , us e a so ft pen c il . T he in f or m a ti on a bo u t t he p r in t s h o ul d a l so be in cl u de d , t he t yp e of p rin t , i. e. sa l t o r a l b u men , ton in g use d a n d t he da te p ho t og ra p h ed a n d da t e p ri n t ed is a ls o u sef u l.

St o ra ge s ho u l d p r o t ec t p r in t s a n d n ega t ive s f ro m h ig h h u m id i t y , te m pe r a t u re , ul t ra vi ole t ra di a ti on , in s ec t s, m o ul d a n d c h e mi ca l a t ta c k f r o m a t mo sp h e re a n d s u r ro u n d in g ma te r ia l s. C a rp e ts , d ra pes a n d o t he r fa b ri cs s h o ul d be a v oi de d in st o ra ge a rea s . T h ey a bs o rb m oi st u r e in h ig h h u m id i t y a n d re lea s e i t in to t he a ir . 94

F R AM I N G

Wh e t he r f ra m in g f o r ex h ib i ti on o r f o r p er son a l u se , t h e ma te r ia l s u se d a re c ri t i ca l in de te r m in i n g t he lif e of t he p r in t . Ca u ses of da ma g e t o p ri n t s a re ef fe c ts of h u mi d i ty , a i r po ll u t ion , hea t , b io l ogi ca l a t ta c ks a n d l i gh t .

L ig h t da m a ge de pen ds on t h re e fa c to rs :

1 . Il l u mi n a n c e.

2 . T he t i me i t is ex po s ed to l ig h t .

3 . T he s pe c t ra l co m p o si ti on of t he lig h t .

As pe r t he re c ip r o ci t y l a w o f p h o to c he m i ca l a c ti on , da ma ge ca use d b y l ig h t is r ela te d d i re c tl y t o t he p r o d u ct o f t he ill u m in a n ce a n d t he t i me of t he e xp os u re o f t he i ma g e t o t he

93 Ke e f e , L au r e n c e E . I n c h , D e n n i s 1 9 9 0 , T h e L i fe o f a P h o t o g r a ph , A r c h i v a l P r o c e s s i n g M at t i n g F r a m i n g S t o r a g e , 2 n d e d i t i o n F o c a l P r e s s , U S A . p . 9 9

94I b i d. p 2 4 8

T he Sa l t p ri n t M a n u a l | S to ra ge a n d F r a m in g 7 6

lig h t . T his m ea n s i f il l u mi n a n c e i s d o u bl ed , t he t i me wh ic h da ma ge o c c u rs is ha lve d . 95

As t he wa ve len g t h dec r ea se s t he des t r u c ti ve p o we r o f l ig h t in c re a ses . T h e r is k da ma ge i s g rea te r in t he b l ue a n d t he ul t ra vi ol e t reg ion s. T he l eve l o f u l t ra v iol e t is s ma l l co m p a re d wi t h t he vis i ble reg ion b u t i t i s ex t re me l y de s t r uc t iv e. 96 L ig h t ra ys s h o r te r t ha n 5 0 0 n a n o me t res p r ov id e en o u g h en e r gy to seve r o rga n ic bon d s in pa pe r . 97 No c on s er va ti on t r ea t men t ca n re st o re l ig h t - da ma g ed ma te r ia l .

U V ra dia t ion ca n b e con t r ol le d b y :

1 . Fil t ra t ion wi t h con s er va ti on g la s s o r Pe rs pe x t rea te d t o bl o ck up t o 9 7 % o f U V . S ta n da r d c le a r gla s s bl oc k s a bo u t 4 7 % of t he da ma gin g ra y s in 3 0 0- 3 8 0 n m ra n g e.

2 . Re d uc in g t he l ig h t i n ten si t y le ve l

3 . Re d uc e t h e d u ra t ion o f t h e ex pos u r e .

95 I b i d. p 1 2

96 C I B S L i g h t i n g G u i de M u s e u m s a n d A r t G a l le r i e s , I E S P u b l i c at i o n s , L o n d o n , 1 9 8 8 p 1 3

97 I b i d . p 1 1

T he Sa l t p ri n t M a n u a l | S to ra ge a n d F r a m in g 7 7

Ext r e mes c ha n ges i n te m pe r a t u r e o ve r a sh o r t pe ri o d o f ti m e c rea te con den sa ti o n . In a i r wi t h h u m id i t y h ig he r t ha n 6 0 % , gela t in a n d a l b u me n a r e fe r ti le c ul t u r e me di a i dea l fo r f un g a l gr o wt h . Ha n dl in g p h o tog r a p h i c ma te r i a ls wi t h o ut g lo ves ma y lea v e fin ge r oi ls deg r a d in g t he s u r fa c e a n d c r ea tin g a n en vi r on men t fo r f u n g us . 98 If co t t on l in t f r ee g lo ves a re n o t a va i la ble , wa s h a n d t ho r o ug h ly d r y ha n ds be fo re ha n d lin g p ho t og ra p hs . Co c k r oa c h es a n d si lv e rf is h a ls o t h r ive on ge l a ti n a n d a l b u m en s ‟ hig h p ro te in con ten t i n t he p rin t , des t r o yin g t he i m a ge wh i le ea t i n g t he p ro t ein . 99

D ue to t he pr o te in l a ye r in a lb u m en p ri n ts a n d sa l t p rin ts wi t h ge la tin bin de r s, n on - b uf fe re d 1 0 0 % c o t ton m u se u m boa r d a r e s ug ges te d . 100 Pla i n s a l t p rin t s a re be t te r p ro t ec te d us in g a l ka l in e b uf fe re d b o a r ds d ue to t he i r su sc ep t i b i li t y to a e r ia l ox i da ti on . 101

98 T i m e – L i f e 1 9 7 2 C ar i n g fo r P h o t o g r a ph s – D i s p l ay , S t o r a g e an d R e s t o r at i o n , T i m e L i f e I n c U S A . p 6 0

99 T i m e – L i f e 1 9 7 2 C ar i n g fo r P h o t o g r a ph s – D i s p l ay , S t o r a g e an d R e s t o r at i o n , T i m e L i f e I n c U S A . p 1 8

100 L am b , A . R . ( 1 9 9 9 ) F r a m i n g P h o t o g r ap h y , C o l u m b a P u b l i s h i n g , O h i o , U S A . p 2 2

101 W ar e , M . J . ( 1 9 9 4 ) M e c h an i s m o f I m a g e D e t e r i o r a t i o n i n E ar l y P h o t o g r a p h s - t h e s e n s i t i v i t y t o L i g h t o f W H F T a l bo t ' s h al i de - fi x e d I m a g e s 1 8 3 4 - 1 8 4 4 , S c i e n c e M u s e u m a n d N at i o n a l M u s e u m o f P h o t o g r a p h y , F i l m & T e l e v i s i o n , B r ad f o r d , L o n d o n . p 5 8

T he Sa l t p ri n t M a n u a l | S to ra ge a n d F r a m in g 7 8

PR OB L EM S

11.

CHAPTER 11

Sa l t p rin t in g ca n be q ui t e f r us t ra t in g d u e to i ts in he ren t sen si t iv i t y t o n u me r us s u b st a n c es . T hi s c rea te s a n u m be r of exa s pe ra tin g res u l ts in c l u din g d if fe ren t t y pes of st a in in g . T hi s c ha p te r li s ts s pe ci fi c p r o ble m s a n d of fe rs po ssi b le s ol u ti on s .

P R O B L E M

C AU S E

S O L U TI O N S

I n c r e a s e t h e c o n t r a s t b y u s i n g p o t a s s i u m d i c h r o m a t e i n t h e s a l t s o l u t i o n . C r e a t e a n e w n e g a t i v e .

Th e n e g a t i v e i s n o t d e n s e e n o u g h t o a l l o w l o n g e n o u g h e x p o s u r e s t o c o n v e r t s i l v e r s a l t s t o m e t a l l i c s i l v e r .

Sa l t pr in ts a re f la t a n d we a k . Yo u ca n n ot ge t a bla c k .

R e - s h o o t o r r e m a k e n e g a t i v e .

Th e n e g a t i v e d o e s n o t h a v e e n o u g h s e p a r a t i o n i n t h e h i g h - l i g h t s o r s h a d o w s .

N e g a t i v e l a c k s c o n t r a s t . Tr y p o t a s s i u m d i c h r o m a t e t o

i n c r e a s e t h e c o n t r a s t , o r r e m a k e a d e n s e r n e g a t i v e .

H u m i d i t y.

P a p e r m u s t b e e x p o s e d wi t h i n 2 h o u r s o f s e n s i t i z a t i o n . L e s s i f t h e r e l a t i v e h u m i d i t y ( R H ) i s h i g h e r t h a n 6 0 % .

S e n s i t i z e d p a p e r l e f t t o o l o n g b e f o r e e x p o s u r e .

P a p e r m u s t b e e x p o s e d wi t h i n 1 h o u r o f s e n s i t i s a t i o n i f R H i s h i g h e r t h a n 6 0 % .

W a s h t h e r o d b e t w e e n e a c h c o a t i n g o f s i l v e r . B r u s h m a y n e e d r e p l a c e m e n t .

Th e r o d o r b r u s h u s e d f o r c o a t i n g t h e s i l v e r n i t r a t e s o l u t i o n i s c o n t a m i n a t e d w i t h s a l t s o l u t i o n .

R e - s h o o t o r r e m a k e t h e n e g a t i v e .

Po o r t on a l ra n ge

Th e n e g a t i v e r e q u i r e s m o r e d e n s i t y a n d i s n o t r e p r e s e n t i n g t h e t o n a l r a n g e o f t h e s c e n e .

T he Sa l t p ri n t M a n u a l | P ro b le ms 7 9

P R O B L E M

C AU S E

S O L U TI O N

S t a i n s

F i x e r e x h a u s t e d .

R e p l a c e f i x e r .

W e t h a n d s o n s e n s i t i z e d p r i n t b e f o r e , d u r i n g o r a f t e r e x p o s u r e .

To w e l d r y h a n d s , h a n d s s h o u l d a l w a ys b e d r y w h e n h a n d i n g t h e p a p e r .

P r i n t l e f t t o o l o n g i n t h e f i r s t w a t e r b a t h , e x c e s s s i l v e r n i t r a t e i n t h e w a t e r c a u s e s s t a i n s .

K e e p a g i t a t i n g b a t h a n d c h a n g e w a t e r a t l e a s t e v e r y 2 m i n u t e s f o r t h e f i r s t 5 m i n u t e s .

P r i n t n o t wa s h e d l o n g e n o u g h i n t h e f i r s t w a s h .

E x c e s s s i l v e r n i t r a t e s t i l l i n t h e p r i n t , f i r s t wa s h m u s t b e a t l e a s t 2 0 m i n u t e s i n t o t a l .

Th e a b s o r p t i o n i n t o t h e p a p e r i s u n e v e n .

S i z e p a p e r o r u s e g e l a t i n i n t h e s a l t s o l u t i o n . M a k e s u r e t h e p a p e r a n d t h e s o l u t i o n a r e a t t h e s a m e t e m p e r a t u r e .

C l e a n wo r k i n g s u r f a c e . M a k e t h e p a p e r l a r g e e n o u g h s o t h e c o a t i n g s o l u t i o n i s n o t n e a r t h e e d g e .

Th e s a l t s o l u t i o n h a s m i g r a t e d t o t h e b a c k o f t h e p a p e r d u r i n g c o a t i n g , d r a w i n g t h e s i l v e r t h r o u g h t h e b a c k .

Tr a ys a r e c o n t a m i n a t e d . W a s h t r a ys , a n d a l l o c a t e

t r a ys f o r u s e o f c e r t a i n c h e m i c a l s .

P r i n t t o o l o n g i n f i x e r .

U s e a t i m e r t o e n s u r e c o r r e c t f i x i n g t i m e .

Y e l l o w i n g o f t h e p r i n t o r ye l l o w s t a i n s

F i x e r h a s d e c o m p o s e d a n d / o r i s a c e t i c .

R e p l a c e f i x e r , u s e s o d i u m c a r b o n a t e t o m a k e f i x e r a l k a l i n e .

S e n s i t i z e d p a p e r k e p t t o o l o n g b e f o r e e x p o s i n g .

Pa pe r m us t be ex po sed wi t h in 1 ho u r o f sen si t i sa t ion i f t he RH i s hi g he r t ha n 6 0% .

I n a d e q u a t e f i x i n g .

D a r k m o t t l e d s t a i n s

E n s u r e f i x e r i s f r e s h , u n c o n t a m i n a t e d a n d f i x i n g t i m e i s a d e q u a t e .

T he Sa l t p ri n t M a n u a l | P ro b le ms 8 0

PR OB L EM

C AU S E

S OLU TI O N

U n e v e n c o a t i n g

Th e w h i t e p a t c h e s a r e c a u s e d b y a n u n e v e n c o a t i n g o f t h e s i l v e r n i t r a t e s o l u t i o n .

A n i n c a n d e s c e n t l o w w a t t a g e l a m p w i t h l i g h t f a l l i n g a t 4 5 ° a c r o s s t h e p a p e r w i l l i m p r o v e v i s i b i l i t y wh e n c o a t i n g .

I m p r o v e c o a t i n g v i s i b i l i t y a n d e n s u r e f u l l c o v e r a g e o f t h e i m a g e a r e a .

Th e d u l l i m a g e a r e a s i n d i c a t e s s a l t h a s n o t r e a c h e d t h e m a n d t h e s i l v e r n i t r a t e o n l y i s r e a c t i n g w i t h t h e p a p e r s o r g a n i c s u b s t a n c e s .

B l a c k S p o t s

S i l v e r n i t r a t e c o n t a m i n a t i o n .

C l e a n a l l t h e u t e n s i l s a n d s u r f a c e s .

W h i t e S p o t s . ( m e a s l e s e f f e c t )

E n s u r e a n e v e n c o a t i n g o f s i l v e r n i t r a t e a t t h e c o r r e c t p e r c e n t a g e i s a p p l i e d .

I n s u f f i c i e n t s i l v e r n i t r a t e s o l u t i o n , t h e i m a g e m a k i n g s i l v e r c h l o r i d e i s w e a k .

Sa l t pr in t is un s ta b le a n d wi l l n o t la s t .

In a de q ua te ex p os u r e, to n in g, f ixi n g , wa s hin g a n d s t o ra g e me t h o ds .

Sil ve r n i t ra t e is da n ge r o us to u se.

S i l v e r n i t r a t e c a n c a u s e p e r m a n e n t e y e d a m a g e . I t s t a i n s t h e s k i n a n d i f a b s o r b e d i s d e p o s i t e d i n v a r i o u s l o c a t i o n s a r o u n d t h e b o d y c a u s i n g s t a i n i n g o f t h e b l o o d v e s s e l w a l l s , g u m s a n d m u c o u s m e m b r a n e s , k n o w n a s a r g y r i a .

I f c o r r e c t l y c o a t e d , e x p o s e d , p r o c e s s e d a n d s t o r e d t h e p r i n t h a s a p r o v e n l i f e s p a n o f a t l e a s t 1 5 0 ye a r s Th e N a t i o n a l G a l l e r y o f A u s t r a l i a h o u s e s s o m e f i n e e x a m p l e s p r i n t e d b y T a l b o t i n t h e e a r l y 1 8 4 0‟ s . S i l v e r n i t r a t e i s d a n g e r o u s i f m i s h a n d l e d . A l w a y s w e a r g l o v e s w h e n m i x i n g o r u s i n g s i l v e r n i t r a t e s o l u t i o n s . W e a r e y e p r o t e c t i o n . T h e s a f e s t m e t h o d o f a p p l y i n g s i l v e r n i t r a t e s o l u t i o n s i s u s i n g a r o d a n d s yr i n g e . S i l v e r n i t r a t e c o a t i n g b a t h s a r e d a n g e r o u s .

B ron z in g .

R e d u c e e x p o s u r e t i m e , d e c r e a s e s o d i u m c i t r a t e o r m a k e a d e n s e r n e g a t i v e .

S a t u r a t i o n p o i n t , t h e p r i n t i s o v e r e x p o s e d . 102 Th e p a r t i c l e s o f r e d u c e d m e t a l l i c s i l v e r m i g r a t e t o t h e s u r f a c e f o r m i n g a l a ye r o n t h e s u r f a c e o f t h e p r i n t .

102 R e i l l y , J . M . ( 1 9 8 0 ) T h e A l bu m e n & S a lt e d P a p e r B o o k : T h e H i s t o r y a n d pr a c t i c e o f ph o t o g r ap h i c pr i n t i n g , 1 8 4 0 - 1 8 9 5 . , L i g h t I m p r e s s i o n s C o r p o r at i o n . , R o c h e s t e r , U S A . p 7 3

T he Sa l t p ri n t M a n u a l | G lo ssa r y 8 1

GL OS S A RY

Ac ti ni c l i g ht : L i g h t in t he U V , vi ole t a n d b l ue reg ion of t he spe c t r u m t ha t i s re q ui r ed f o r lig h t -in d u ce d c he m i ca l r ea c t ion s in p ri n t in g -o u t p ro c esses t o c rea t e a n i ma ge .

Al k al i ne : O p p osi t e of a c i d wi t h a pH gr ea te r t ha n 7 on a p H sca le .

An hy dr ou s : F re e f r o m wa te r .

t u be r o us r oo t s,

Ar r o wr o o t: S ta r c h ma de i n c l u din g f ro m po ta t oes . I t is a fin e whi t e p o wd e r t ha t is use d f o r si zin g a n d bin d in g .

Bi nde r: T he s u bs t a n ce t ha t b in d s t oge t he r t wo o r m o re ma te r ia l s or c h e mi c a ls in a m ix t u re , e . g. gel a t in a n d a l b u men bin de r s ho ld t h e c h lo r i de , di s pe rs in g t he si lve r c h lo ri d e w hi le a d he r in g i t to t he p a pe r .

Bro nzi ng : T hi s de s c ri be s t he sa t u ra ti o n poi n t of a sa l t p rin t exp os u re . T he me t a lli c s il ve r pa r ti c le s si t s o cl ose t oge t he r t he y f o r m a la ye r o n t he s u rf a c e.

Buc kl e Bru s h : A te st t ub e, gl a ss o r p la s ti c t u be wi t h c o t to n wo o l t wis t ed t ig h tl y in o n e en d.

Ca me ra L uc i da : N o t a c t ua ll y a ca me r a b u t a n o p ti ca l d ra wi n g a id .

D. ma x is t he ma xi m u m den s i t y r ec o r de d on f il m o r pa pe r .

D. mi n i s t h e m in i m u m den s i t y r ec o r de d on f il m o r pa pe r .

Dec a -h yd ra te d : C on ta i n s 1 0 m ol ec u le s of wa te r .

De -i o ni ze d Wa ter : Wa t e r p u r if ie d f r o m a ll in o r ga n i c sa l ts b y a n io n ex c ha n ge p r oc ess o r r eve r se os m osi s b u t ma y s ti ll ha ve o rga n ic co m p o un ds .

Del i que sc en t : A bs o r bs wa te r f r o m t he a i r .

De - mi n er al i ze d W at er : Sa me a s dei on i s ed wa te r .

Den si ty : A mea s u r e of li g h t a bs o rb ed o r t ra n s mi t te d in a n a rea of a n i ma ge . T his c a n be m ea s u re d b y a den s i to m e te r . Den si t y is a l oga ri t h m i c v a l ue. If on e a rea of a n eg a ti ve t ra n sm i ts t wi c e a s m uc h l ig h t a s a n o t h e r t he d en si t y d if fe ren ce i s 0. 3 (i .e . t h e lo g of 2 )

T he Sa l t p ri n t M a n u a l | G lo ssa r y 8 2

Den si ty R ang e : T h e d if fe ren ce b et wee n t h e l ig h te s t re co r de d a rea a n d t he da r k es t r ec o r de d a r ea . In fi l m i t r efe r s to mea s u rin g t h e t h in n es t pa r t o f t h e n e ga t iv e, t hen me a s u rin g t he d en se st pa r t o f t h e n e ga ti ve a n d su b t ra c tin g t h is va lu e. T his wi l l gi ve y o u t he den s i t y ra n ge . Den si t o me te r s a r e us ed to a c c u ra te ly m ea s u re den s i t y.

Di s ti l l ed wa te r : All i m p u ri t ies a re re m ove d by bo il in g wa t er a n d re con den sin g t he s t ea m.

Ef fl ore sc e n t : L ose m ois t u r e.

E xo t her mi c : C rea te hea t wh e n d iss ol vin g .

Fadi ng : D e te ri o ra ti on of t he sa l t p rin t t h ro u g h p oo r fix i n g, in c o m ple t e wa s h in g o ut of fix e rs a n d a i rb o rn e con t a min a ti on a t t ri b u te t o fa din g.

Fi xe r: A m m on i u m t hi os u lfa t e a n d so di u m t h io s ul p ha te a re us ed to re m o ve t he un ex pos ed , t h e ref o re s t il l l ig h t sen s i ti ve sil ve r sa l ts .

Fog : Non -i m a ge si l ve r t ha t s ho ws a s di sc ol o u ra ti on , us u a ll y c rea te d b y c on ta mi n a t ion o r ex po s u re on t h e li g h t sen si ti ve su r fa ce b ef o re b ein g pla ce d un de r a n e ga t iv e f o r p rin t in g .

Gel a ti n : A p r ot ein bin de r c rea te d f ro m a n i ma l h i des , b on es a n d ti ss ues . I t is a n i mp o r ta n t bin d er in p h o to g ra p hy a n d si zin g in pa pe r ma k in g . V a r io u s g ra des a re a va i la ble .

L ate n t Im ag e: An in vis i ble i ma g e f o r me d on sen s i tis e d fi l m or lig h t . T h e e xp os u re c rea tes s ma ll pa pe r b y ex p os u r e to cl u st e rs o f si lve r a t o ms in s il ve r h a li d e cr y st a ls t ha t a re i m a ge fo r m in g wi t h c he m i ca l de vel o p men t .

L ati t ude : T h e a c c ep ta bl e ra n ge of a n i ma g e b ef o re ove r - exp os u re a n d un de r -ex po s u re ca u se l os s of de ta i l.

L i nt er s: F i b res u s ed t o ma k e co t t on pa pe r . T hes e a re t h e sh o r te r f i b res l ef t a ft e r t h e c o t ton ha s gon e t h r o ug h t he gin n i n g ma c hin e . T he l on g e r fi b re s a r e ma de in t o t h r ea d.

Me a sl e s: Bl o t c h y li gh t m a r ks ca use d b y in s u ff i cien t si l ve r, a lso use d t o des c r ib e da r k ma r ks ma d e fr o m p oo r o r ex ha u st ed fix in g ba t h .

M on o- hy dr a ted : Co n ta in s on e m ol ec u le o f wa te r .

M S DS : M a te ria ls S a fe t y Da ta S he e t s . T he se p ro vi d e a f ul l des c r ip t ion of t h e c he m i ca l s, sa fe ha n d lin g , p r ot ec ti on re q u ir e d a n d f i rs t - a id t rea t m en t.

T he Sa l t p ri n t M a n u a l | G lo ssa r y 8 3

O xi da ti o n: T he re m ova l o f a n ele c t r o n o r e le c t ron s f r o m a n a t o m o r a m o le c ule .

Ph o t oc h e mi c al Ac t i on : A c ha n ge ca n on l y be ma de b y li gh t t ha t is a bs o rb e d. T he a m o un t o f p h ot o c he m ic a l c ha n g e is p ro p o r ti on a te to t he li g h t in ten si t y m u l ti pl ie d by t i me of ill u m in a t ion .

Ph o t ol y si s: In t he sa l t p rin t i t is t h e a c ti vi t y c rea te d b y t he exp os u re to l ig h t t ha t c ha n ge s t he s il ve r c h lo r id e t o m et a lli c sil ve r .

Pu ri fi e d W at e r : T hi s gen e ra ll y m ea n s wa te r p u r if ie d fo r h u ma n con s u m p ti o n whi c h s ti ll ma y c on ta in sa l ts a n d o r ga n i c ma t te r .

Py r o: An o r ga n i c de vel o pe r a g en t f o r p h o to g ra p hi c f i l ms . O t he r n a me s use d a re p y r oga ll ol , p y ro ga l li c a c id o r t ri h y d r ox y ben zen e . It off e rs a n exc e p ti on a l t on a l ra n g e a n d in c re a se hi g hl ig h t s epa ra t ion . P r y o is t oxi c .

Rag : T hese a re o l d ra g s o r n e w o ff - c u t s of c o t ton fa b r ic t ha t a re b r o ken do wn to ma ke pa pe r . Ra g t h rea ds o ri gin a ll y c o me fr o m t he l on ge r s t r on ge r f i b res o f t h e co t ton pla n t , a l t h o ug h pa pe r is n o t o f ten ma de f r o m t h e ra gs to da y, i t ma ke s a ve r y st r on g pa pe r .

Rati o : T h e r ela t ion sh i p be t ween t wo q ua n ti t ies . F o r exa m pl e 1 : 3 m ea n s on e pa r t wa t er a n d t h ree pa r ts c he m ica l .

a mo le c ule . O x id a t io n

a n d

Reduc ti on : T he a d di t ion o f a n el ec t r on o r e le c t ron s f r o m a n a t o m o r re d uc t ion o cc u r si m ul ta n eo u sl y , a r ed u cin g a g en t i s a s ub s ta n c e wh i c h g ive s u p ele c t r on s a n d b e co m es ox i di ze d .

Refl ec ti on: Fo r s mo ot h s u rfa ce s a n g le o f in ci den ce is t he sa me a s t he a n g le o f re fl ec ti on , wh en li g h t st r i kes t he s u rfa ce t he lig h t b o un ce s ba c k a t t he sa me a n g le . Fo r o t h e r s u r fa c es t he lig h t i s r ef le c te d ba c k a t di ff er en t a n gl es. i .e . s ca t te re d .

Re fr ac ti o n: W hen li gh t p a sse s t h o ug h on e m ed i u m t o a n o t he r a ra y is ben t s h a rp ly a t t he s u r fa ce b et we en t he m . In a p rin t t hi s a f fe c ts t he a p pea ra n ce of t h e si l ve r wh en t h e g los sie r a lb u m en ref ra c ts t he lig h t . T h e p r in t a p pea rs da r ke r in t he sha d o ws a n d l ig h te r in t he hi g hl ig h ts t h a n sa l te d pa pe r p rin ts .

Sa t ur a ted S ol u ti on s: (P o ta s si u m di c h r o ma te is of ten use d in a sa t u ra t ed so l u ti on ) . Th e c he m i ca l is a d de d to l i q ui d un ti l s o me is l ef t un di ss ol ve d . I t ca n n o t a bso r b / d iss ol ve a n y m o re of t he c he m ica l , i t is sa t u r a te d . A hi g he r t e m p era t u r e ma y ca use t hi s

T he Sa l t p ri n t M a n u a l | G lo ssa r y 8 4

to d iss ol ve i t b u t wh en i t co ol s a p ro p o r ti on o f i t wil l p re ci pi t a t e .

Se l f - ma s ki ng : T h e t hin n e r a r ea o f t he n e ga ti ve a l lo ws t he sil ve r c h lo r id e con v er t to me ta l li c si lv e r in t h e p rin t . T hi s n o w da r ke r s u r fa ce of t he sa l t t h u s f o r ms a “ ma s k ” . T h e ex p o sin g lig h t is he ld ba c k f r o m rea c hin g t h e un re d u ce d si lv e r c h lo ri de un de rn e a t h . M e a n w hi le t he r es t o f t he sa l t p r in t con t in ue s t o exp ose un de r t he m o re d en se pa r ts o f t he n e ga ti ve .

Se n si t o me tr y: T h is seek s t o es ta bl is h a rela t ion s h i p be t we en exp os u re a n d den s i t y p h o to g ra p hi c ma t er ia l .

Si zi ng : T he s ub s ta n ce a d de d to pa pe r to in c rea s es s u r f a ce st re n g t h . I t r es is ts t he pen e t ra t ion o f s ol u ti on s in t o t h e fi b res of t h e pa pe r . Gela t i n a n d s ta r c h a re t h e mos t co m m on t y pe s o f si zin g .

in

S te p We dg e: T h is i s ei t he r a t ra n spa r en t fi l m o r pa pe r wi t h den s i t y in c re men t s of 0. 1 5 o r 0. 3 0 . A we d ge o f 2 1 s te ps wi t h den s i t y un i ts of . 1 5 s te p in t e rva ls gi v e a to ta l ra n ge of 3 . 0 5 den s i t y un i t s. B y c o un ti n g t he n u m be r of di st in c t s te ps in t he p rin t a n d m u l ti pl y i n g b y t he . 1 5 den s i t y in te r va l b et ween t h e loga r i t h mi c un i t s . To st ep s gi ves t he e xp os u re ra n g e con ve r t t hi s ra n ge to s to ps , m ul t i pl y t he lo g u n i ts b y 3. 3 . 103 O t he r n a m es : s te p t a bl e t, o pt i ca l we d ge a n d t ra n s m is si on g re y sca le .

We tti ng A g e n t : A p u ri fi ed de te rg en t us ed in t he f in a l wa s h in g sta ge of f il m p r oc e ssin g , ca u sin g wa te r t o r un of f e ven l y t h us re d u cin g r u n ma r k s a n d wa t e r s p ot s.

103 C t e i n ( 1 9 9 7 ) P o s t E x po s u r e - A dv an c e T e c h n i q u e s fo r t h e P h o t o g r a p h i c P r i n t e r , B u t t e r w o r t h - H e i n e m a n n , W o b u r n M A U S A . p 3 5

T he Sa l t p ri n t M a n u a l | G lo ssa r y 8 5

AP P E N DIX 1 C H EM IC AL S

S AF E TY N O T E S

TRE A T AL L C HEM IC A L S AS D A NG ERO U S O R PO I SO NO U S

o A L W A Y S a d d a c id t o wa t er , NE V ER wa te r t o a ci d. A l wa ys we a r

eye p ro t ec t ion a n d glo ve s .

o Al wa y s d iss ol ve in t he o rd e r o f t he f o r m u la

o Wa i t un t il on e c he m ica l h a s c o m ple t el y di ss ol ve d be fo re

a d din g t h e n ex t.

o U se a f un n e l to po u r s ol u t ion s in to b ot t les . Rin s e f un n e l

a ft e r u se .

o U se p la s ti c o r gla s s st i r rin g r o ds .

o L a be l a ll c on ta in e r s wi t h c he mi ca ls , d a te mi xe d a n d u sa g e

ra ti o i f r eq u i re d .

o D o n o t s to r e c he m i c a ls in f oo d f r i dge .

Ch e mi ca ls a f fe ct t h e bo d y b y :

o A bso r p t ion : En te rs t he bo d y t h ro u g h t he s k in a n d in to t he bl oo d s t rea m . Cu ts o r wo u n ds ea sil y a bso r b c he m ica ls . W hen m ixin g c h e mi ca l s, us e gl ov es f r o m c he m ica l s u p pli e rs . Su pe r m a r k e t t y pe glo ves o f ten do n o t of f e r s t ron g en o ug h p ro t ec t ion .

o B rea t h in g : A i rb o rn e c he mi ca ls , s uc h a s d us t, ga se s a n d va p o u rs , c a n en te r t he bo d y t h o u g h t he n o se a n d m o u t h. I f yo u r wo r k en vi r on men t is n ot wel l v en ti la te d , m ix c he mi ca ls o u t d oo rs ( b ree ze b lo wi n g a wa y f r o m yo u fa c e) . M a ke s u r e yo u ha ve ga s ma s k s t o p r o te c t a ga in s t c he m ica l f u m es.

o

In g es ti on : D o n o t e a t o r d r in k i n t he a rea wh e re yo u a re wo r k in g o r mix in g c he m i ca ls . 104

Kee p to ps a n d ca p s ti g h t l y cl ose d a s so me c he m ica ls wi l l a bs o r b t he m ois t u r e f ro m t h e a i r ( kn o w n a s del iq u es cen t ). T his wi l l a l t e r t he wei g h t a n d m a y a l lo w a c r us t to fo r m on t he

104 J am e s , C . ( 2 0 0 2 ) T h e B o o k o f A l t e r n a t i v e P h o t o g r a p h i c P r o c e s s e s , D e l m a r , N e w Y o r k . p 3 4 4

T he Sa l t p ri n t M a n u a l | A pp en dix 1 C he m ica ls 8 6

O t he r s

los e t h ei r m ois t u r e

(ef fl o res ce n t ) , h a ve su r fa ce . da n g e ro u s f u mes , o r eva p o ra te . Ea c h t i me y o u b u y c he m i ca l s c he c k t h ei r M a te r ia l s Sa fe t y Da ta S h ee t fo r c o r re c t s to ra ge a n d ca re .

Te m pe ra t u re s in mi xin g f o r m ul a s a re i m po r t a n t so f ol lo w t he in s t r u ct io n s , a s so me :

o re q u ir e wa r m wa te r te m pe ra t u r e t o d iss ol ve

o c rea te hea t wh e n d i sso lv in g (k n o wn a s exo t he r m i c)

o so me a bs o r b he a t ( k n o wn a s en do t h e r mi c)

D iss ol ve c h e mi ca l s in t he o r de r t h e fo r m u la lis t s a n d wa i t un ti l ea c h c he m i ca l ha s di ss ol ve d be fo r e a d din g t h e n ex t.

M E AS U R I N G O U T C H E M I C A L S :

in d is pen sa ble . Ele c t ron ic Ac c u ra te sc a le s a re di gi ta l s ca l es a re re la ti vel y in ex pe n siv e. T he a c c u ra c y a n d ra n g e ca pa c i t y wil l re f lec t in t he p ri ce . S ca les to m ea su r e 0 . 0 1 of a gra m wi ll be m o re exp en si ve t ha n t h ose t ha t mea s u re 0 . 1 0 g m . P la ce a s he et of pa pe r un de r t he s c a les in ca se o f s pi ll a ge. D o n o t pl a c e c he m i ca l s di re c tl y on t o t he weig h in g pla t e of t he s ca le s. Pla ce a s ma ll s he et of pa pe r on t he we ig h in g p la te fo r mea s u rin g s ma ll e r a m o un ts . F o r mea s u ri n g la rge r a m o un ts of d r y c h e mi ca ls us e d is po sa b le pa pe r o r pla s ti c c up s. Re m e m be r t o co m pen sa t e fo r t h e ex t ra m a s s in t he mea s u re men t s wh e n u sin g a c u p o r pa p e r.

C O N V E R S I O N S O F M E A S U R E M E N TS

o Weig h t s: To con ve r t g ra m s t o o un ce s

Di vi de t he ( g m) g ra m s b y 2 8 . 4 = o un ce s.

o L iq u i d m ea s u re m en t s: M i ll il it r es ( m l ) t o fl ui d o u n c es .

Di vi d e m l b y 2 8 . 4 = i m pe ria l fl u i d o un c e .

o M ea s u re me n t in a r e a :

Cen ti m e t res t o in c hes , c m x 0 . 3 9 3 7 = in c hes .

In c he s t o c en t i me t res , in c he s x 2 . 5 4 0 0 = c m .

Exa m pl e fo r 8 x 1 0 in c hes = 2 0. 3 2 c m x 2 5. 4 c m .

o Te m pe ra t u re : T o c o n ve r t Ce lsi u s t o Fa h ren h ei t

1 . M u l ti pl y t he te m pe r a t u re i n Cel si us b y 9 .

T he Sa l t p ri n t M a n u a l | A pp en dix 1 C he m ica ls 8 7

2 . D iv id e a n s we r b y 5 . 3 . A dd 3 2 to t he res u l t .

Exa m ple f o r 2 0° C

1 . 2 0 x 9 = 1 8 0 2 . 1 8 0 ÷ 5 = 3 6 3 . 3 6 + 3 2 = 6 8 ° F

o Pe r cen ta ge so l u ti on s : Kn o wn a s p e rc en t wei g h t fo r v ol u m e

(% w/ v )

Pe r cen ta ge s ol u t io n s a re u se d wh e n t h e q u a n ti t y of t he c he m ica l is t o o sm a ll t o wei g h t a c c u ra te l y .

fo r vo l u me : 2%

Fo r exa m p le : pe rc en t a ge w e ig h t sol u t ion is 2 g m in 1 0 0 ml of s ol u t ion .

P er c e nt a ge vo l u me fo r vo l u me 2 % sol u t ion i s 2 ml in 1 0 0 ml of s ol u t ion .

C H E M I C A L S U S E D I N T H I S M A N U AL

A M M O N I U M C H L O R I D E N H

Cl

4

o A pp ea ra n ce : W h i te od o u rl ess c r ys ta l s o r p o wd e r .

o Ha z a rd s : Ha r mf u l if s wa ll o we d , i r ri t a n t to t he e ye s,

re s p i ra to r y s ys t e m a n d s kin .

o O t he r n a m es : Sa l a m m on ia c , m u ria te o f a m m on ia .

o S ub s ti t u te : sodium chloride, calcium chloride, potassium

chloride.

o U ses : Sa l t s ol u t ion i n sa l t a n d a l b u m en p rin t in g .

o Ava ila b le f r o m: C h e m ica l s u p pli e rs .

A M M O N I U M T H I O C Y A N A T E N H

SC N

4

o A pp ea ra n ce: W h i te od o u rl ess c r ys ta l s o r p o wd e r

o Ha z a rd s: Ha r mf u l if s wa ll o we d , i r ri t a n t to t he e ye s,

re sp i ra to r y s ys t e m a n d s kin .

o O t he r n a m es : A m m o n i u m r h o da te

o S ub s ti t u te : Nil

o U ses : To n in g fo r sa l t a n d a l b u men p rin t in g .

o Ava ila b le f r o m: C h e m ica l s u p pli e rs .

A R R O W R O O T ( S T A R C H S I Z I N G / B I N D E R )

o A pp ea ra n ce: F in e whi t e p o wd e r

o Uses: Sizing or binder

T he Sa l t p ri n t M a n u a l | A pp en dix 1 C he m ica ls 8 8

o Ava ila b le f r o m: S up er ma r k e ts

C A L C I U M C H L O R I D E C a Cl

2

o A pp ea ra n ce: W h i te od o u rl ess f la kes o r po wd e r

o Ha z a rd s: Ha r m f ul i f s wa ll o we d , i r r i ta t in g t o t he e ye s,

re sp i ra to r y s ys t e m a n d s kin .

o Other names: Calcium(II) chloride.

Sodium

chloride,

ammonium

chloride,

o S ub s ti t u te :

potassium chloride.

o Uses: Salt solution in salt printing.

o Ava ila b le f r o m: C h e m ica l s u p pli e rs .

C A L C I U M C A R B O N A T E Ca C O

3

o A pp ea ra n ce: W h i te od o u rl ess po wd e r o r l u m ps .

o Ha z a rd s: E ye , res p i r a t o ry a n d s ki n i r ri ta n t .

o O t he r n a m es : Li m es t on e , c al ci t e , ar a g on i t e , ch al k .

o U ses : To n in g .

o Ava ila b le f r o m: C h e m ica l s u p pli e rs .

H

O

C I T R I C A C I D C

C O O H)

7 C (O H) C O OH .( C H

8

6

2

2

o A pp ea ra n ce: C ol o u r less , o d o u rle ss c r y sta ls o r g ra n ule s , eff lo re sc en t in d r y a i r, d el iq u es cen t i n m oi s t a i r . V e ry sol u b le in wa te r .

i r r i ta n t. Res pi ra t o ry a n d s kin

o Ha z a rd s: S ev e re e ye

ir r i ta n t .

o O t he r n a m es : H y d r o g en ci t r at e

o S ub s ti t u te : S od i u m c i t r at e , cal ci u m ci t r a t e

o U ses : S to p ba t h

o Ava ila b le f r o m: C h e m ica l s u p pli e rs o r h ea l t h fo o d s to r es

G E L A T I N ( B I N D E R / S I Z I N G )

o A pp ea ra n ce: L ig h t ye ll o w o r c ol o u rle s s c oa rse p o wd e r ,

fla kes o r s hee t s.

o Ha z a rd s: Ni l

o O t he r n a m es : Gela t i n e

o Uses: Sizing and as binder. Swells and absorbs up to 10

times its weight in water.

o Ava ila b le f r o m: C h em i ca l s u p pl ie rs a n d s u pe r ma r ke t s ,

n o te: fo o d gela t in ma y ha v e a d d i ti ves .

G L A C I A L A C E T I C A C I D C H

CO O H

3

o A pp ea ra n ce: C ol o u rl ess p un gen t s m el l. Fre e zes a t 1 6 . 6° C

T he Sa l t p ri n t M a n u a l | A pp en dix 1 C he m ica ls 8 9

o Ha z a rd s: C o r ros iv e. I t s va p o u r ca u ses i r ri ta t ion to t he eye s, a d r y a n d b u r n in g n os e, s o re t h r o a t a n d con ges t ion to t he l un gs . Fl a m m a bl e.

Ac et i c

a c i d;

et ha n oi c

a ci d,

o O t he r

n a m es : me t ha n e ca rb ox y li c a ci d .

o Uses: Fermenting albumen solution .

o Ava ila b le f r o m: C h e m ica l s u p pli e rs .

G O L D C H L O R I D E S O L U T I O N 1% Na A u Cl

4

o A pp ea ra n ce: Pa l e go ld l i q ui d .

o Ha z a rd s: C o r ro si ve, des t r u c ti ve of m u co u s m e m b ra n es so a l wa ys ha n dle wi t h g lo ves a n d go gg l es , di r ec t c on ta c t sh o ul d be a v oi de d .

S od i u m

te t ra c hl o r oa u ra te ,

o O t he r

so d i u m t ri c hl o ri de go ld ( I I I ) c hl o ri de

n a m es : c hl o roa u ra t e a ci d go ld t ri h y d ra te .

o S ub s ti t u te : Hydrogen t e t ra c h lo r oa u ra te ( I I I)

o Uses: Gold toning.

o Ava ila b le f r o m: C h e m ica l s u p pli e rs .

G L Y O X A L C

H

O

2

2

2

o A pp ea ra n ce: C lea r l i q ui d .

o Ha z a rd s: Ha r m f ul if in ge st e d o r i n ha le d, i r ri ta n t t o s k in eye s a n d re sp i ra to r y t ra c t. A l wa ys ha n dl e wi t h g lo ves , ma sk a n d g og gle s , d ir ec t con ta c t m us t b e a vo id ed .

o O t he r n a m es :

o Uses: Hardening gelatin.

o Ava ila b le f r o m: C h e m ica l s u p pli e rs .

I S O P R O P Y L A L C O H O L C

H

O

3

8

o A pp ea ra n ce: C ol o u rl ess l iq u i d, s li g h t o d o u r of a l c o ho l.

o Ha z a rd s: F la m ma bl e , t ox ic .

o O t he r n a me s: R u b bin g a l co h ol , is op r opa n ol , p r o p a n o l

a lc o ho l .

o Uses: Hardening albumen coatings.

o Ava ila b le f r o m: C h e m is ts , c h e mi ca l s up pl ie rs .

M E T O L C

H

NO

7

9

o A pp ea ra n ce: W h i te t o ye ll o wi s h p o wd e r .

o Ha z a rd s: Ca u ses s k i n po ison in g . W ea r g lo ves .

T he Sa l t p ri n t M a n u a l | A pp en dix 1 C he m ica ls 9 0

o O t he r n a m es : El on , pi c to l p h o t ol .

o S ub s ti t u te : Phenidone.

o Uses: Developing agent for films.

o Ava ila b le f r o m: C h e m ica l s u p pli e rs .

P O T A S S I U M C H L O R I D E K Cl

o A pp ea ra n ce: C ol o u rl ess wh i t e p o wd e r o r c r y s ta ls .

o Ha z a rd s: A ffe c ts ca r dia c m u sc le s . Hi g h d oses ca n c a use

ca r dia c a r res t a n d r a pi d dea t h .

o O t he r n a m es : C hl o ri de o f p o ta s h , m u ria te o f p o ta s h .

o S ub s ti t u te : Sodium chloride, ammonium chloride, calcium

chloride.

o Uses: Salt solution for salt and albumen printing .

o Ava ila b le f r o m: c he m ica l s u p pli e rs .

P O T A S S I U M C H L O R O P L A T I N I T E 2 0 % K

P t Cl

2

4

o A pp ea ra n ce: R ed d i s h s ol i d

o Ha z a rd s: Po is on o u s , c o r ro si ve to h u ma n sk in , ca n ca use

a ll er gi c ef f e c t s , i s a n exp er i m en t al m u t a g en .

o O t he r n a m es : Potassium tetrachloroplatinate , potassium

Chloroplatinite.

o S ub s ti t u te . Nil

o Uses: Toning.

o Ava ila b le f r o m: C h e m ica l s u p pli e rs .

P O T A S S I U M D I C H R O M A T E K

Cr

O

7

2

2

o A pp ea ra n ce: B ri g h t re d o ra n ge c ry s ta l s

ha r m f u l

a q ua t ic

t he

t o

o Ha z a rd s: Tox i c if s wa l lo we d o r b y in ha l e d. I r ri ta n t t o sk in a n d r es pi ra t o r y s ys te m . Ca n ca u s e se ri o us da ma ge to en vi r on men t , e ye s, ca r cin ogen i c.

o O t he r n a me s: Bi c h r o ma te of po ta s h , Bi c h r o ma te o f po ta ssa , p o ta s si u m bi c h r o ma te , r ed c h r o ma te o f p o ta s h .

o S ub s ti t u te : Ammonium dichromate.

o Uses: increases contrast in salt & albumen printing.

o Ava ila b le f r o m: C h e m ica l s u p pli e rs .

P O T A S S I U M I O D I D E K I

o A pp ea ra n ce: W h i te c r ys ta ls , p o wd e r o r g ra n u les .

o Ha z a rd s: M il d i r ri ta n t . A ffe c ts t h y ro i d.

T he Sa l t p ri n t M a n u a l | A pp en dix 1 C he m ica ls 9 1

o O t he r n a m es : I o din e o f p o ta s h .

o S ub s ti t u te : Sodium iodide.

o Uses: Test for residual fixer.

o Ava ila b le f r o m: C h e m ica l s u p pli e rs .

P O T A S S I U M P E R M A N G A N A T E K Mn O

4

o A pp ea ra n ce: P u r pl e /b la c k c ry s ta l s wi t h a m e ta l li c

lu s t re .

o Ha z a rd s: Po we rf u l o xid is in g a g en t .

o O t he r n a m es : Pe r ma n ga n a te o f p o ta s h . Con d y‟ s c r ys ta ls

o S ub s ti t u te : Sodium permanganate.

o Uses: Test for residual fixer.

o Ava ila b le f r o m: C h e m ica l s u p pli e rs .

P Y R O G A L L I C A C I D C

H

(O H)

6

3

3

o A pp ea ra n ce: W h i te po wd e ry c r ys ta ls .

if s wa l lo we d , t o uc h ed o r

o Ha z a rd s: P oi son o u s , t oxi c

in ha l e d , wea r ma s k a n d g lo ves .

o O t he r n a m es : P y ro , P y ro ga l lo l , t ri h y d r o xben zen e .

o Uses: Active agent in processing negatives .

o Ava ila b le f r o m: C h e m ica l s u p pli e rs .

S I L V E R N I T R A T E Ag N O

3

o A pp ea ra n ce: C ol o u rl ess f la t c r ys ta ls .

o Ha z a rd s: O xi di zi n g a gen t . Wea r e ye p ro t ec t ion , g lo ves a n d ma s ks . Ca n ca u se pe r ma n en t da m a ge to e yes , b u rn s on con ta c t t o e ye s o r s k in , a n d is h a r m f ul t o a q ua t ic en vi r on men t .

o O t he r n a m es : N i t ra t e of si lv e r, l u n a r ca us t ic .

o Uses: Sensitising salted paper, albumen and numerous other

alternative processes.

o Ava ila b le f r o m: C h e m ica l s u p pli e rs .

S O D I U M A C E T A T E CH

C O ON a . 3H

0

3

2

C ol o u rl ess ,

t ra n s pa re n t

ef fl o res cen t

o A pp ea ra n ce: c r ys ta l s

o Ha z a rd s: Ir r i t an t , ke ep co ol in ti g h tl y se a le d b o t tle .

o O t he r n a m es : A ce ta t e of s oda , s o di u m e t ha n oa te .

o Uses: Lower acidity in toning.

o Ava ila b le f r o m: C h e m ica l s u p pli e rs .

T he Sa l t p ri n t M a n u a l | A pp en dix 1 C he m ica ls 9 2

S O D I U M B I S U L F I T E N aH S O

3

o A pp ea ra n ce: W h i te c r ys ta ll in e p o wd e r

o Ha z a rd s: Ha r mf u l if s wa ll o we d o r i n ha l ed .

o O t he r n a m es : A ci d s ul fi t e of s o da

o S ub s ti t u te : Sodium metabisulfite.

o Uses: Pyro developer.

o Ava ila b le f r o m: C h e m ica l s u p pli e rs .

S O D I U M C A R B O N A T E Na

C O

a n d N a

C O

.H

0 a n d N a

CO

.1 0H

0

2

3

2

3

2

2

3

2

o A pp ea ra n ce: W hi t e o r co lo u r les s po wd e r , g ra n ule s o r

c r ys ta l s .

o Ha z a rd s: E ye , s ki n a n d res pi ra t o r y i r ri ta n t .

o O t he r n a mes : So da , wa s h in g so da , ca r bon a t e o f s o da ,

so da a s h .

o S ub s ti t u te : Potassium carbonate.

o Uses: Reducing acidic conditions in the fixer.

o Ava ila b le f r o m: C h e m ica l s u p pli e rs .

S O D I U M C H L O R I D E Na C l

o A pp ea ra n ce: W h i te po wd e r o r c ol o u rl es s c r ys ta l s .

o Ha z a rd s: Ca n ca us e eye s k in a n d re s pi ra to r y i r r i ta ti on .

o O t he r n a m es : Ta ble sa l t, co m m on sa l t .

o S ub s ti t u te : Potassium chloride.

o Uses: Salt solution for salt and albumen prints.

o Ava ila b le f r o m: He a lt h fo o d s to re s ( c he c k t he re a re n o

a d di t ive s) , c h e mi ca l s u p pl ie rs .

Pd Cl

2

4

S O D I U M C H L O R O P A L L A D I T E Na

o A pp ea ra n ce: Re d b r o wn c r ys ta ll in e po w de r o r c r ys ta l s .

o Ha z a rd s: Po is on o u s, Do n o t in ge s t , b rea t he d us t o r m is t .

D o n o t ge t in e y es , on s kin o r cl o t hin g.

o O t he r n a m es : S o di u m c hl o ro pa l la da te (I I ); co d i u m

te t ra c hl o r opa lla d i u m (I I ) ; so d i u m c h lo r opa lla d i te ( I I ) .

o Uses: Toning.

o Ava ila b le f r o m: C h e m ica l s u p pli e rs .

S O D I U M C I T R A T E Na

C

H

O

3

6

5

7

o A pp ea ra n ce: F in e whi t e o do u r les s c r ys t a ls .

o Ha z a rd s: Ir r i t an t t o ey es s k i n an d r e s p i r at or y s y s t em .

T he Sa l t p ri n t M a n u a l | A pp en dix 1 C he m ica ls 9 3

o O t he r n a m es : Tr i s od i u m ci t r a t e .

o S ub s ti t u te : C al ci u m ci t r at e, ci t r i c a ci d .

o

Uses: In salt prints to decrease contrast increases light sensitivity.

o Ava ila b le f r o m: C h e m ica l s u p pli e rs .

S O D I U M H Y D R O X I D E Na OH

o A pp ea ra n ce: W h i te de li q ues cen t l u m p s , fla ke s, bea ds o r

st ic k s .

o Ha z a rd s: Hi g hl y to x ic , c a us ti c , wi ll ex p lo de in h o t wa te r , va p o u r is da n ge r o us , wea r fa ce ma s k gl ov es a n d e ye p ro t ec t ion . In ge s ti o n ca n be fa ta l .

o O t he r n a m es : C au s t i c al k al i , c au s t i c s od a .

o S ub s ti t u te : P o ta s si u m h y d rox i de.

Uses: Test for remaining fixer in print.

o

o Ava ila b le f ro m : C h em i ca l s u p pl ie rs a n d s u pe r ma r ke t s

(„ D r a in o ‟ f o r c lea r in g bl o c ke d d ra in s ) .

S O D I U M M E T A B O R A T E N aBO

.4 H

0

3

2

o A pp ea ra n ce: W h i te c r ys ta ls .

o Ha z a rd s: M o de ra te ha za r d on in ges t io n a n d in ha la ti on ,

sli g h tl y tox i c on s ki n .

o O t he r n a m es : K o da k ba la n ce d A l ka l i, K o da l k

o S ub s ti t u te : Bo ra x, s od i u m te t ra bo ra t e

o Uses: Film developer.

o Ava ila b le f r o m: C h e m ica l s u p pli e rs .

S O D I U M S U L P H I T E Na

S O

2

3

o A pp ea ra n ce: W h i te c r ys ta ls o r po wd e r .

o Ha z a rd s: Po ssi b le m u ta g en . Ha r mf ul b y

in ha la ti on , in ge st io n a n d s k in c on ta c t . Ey e s k in a n d res pi ra t o r y ir r i ta n t . P r ol on g ed o r re pea te d e xp os u re ca n ca us e a lle r gi c rea c ti on s . M ixe d a ci d re lea s e s s ul p h u r di ox id e ga s .

o O t he r n a m es : S ul p h i te , s ul p h i te o f so da .

o S ub s ti t u te : Sodium bisulphite.

o Uses: Hypo clearing bath assists removal of the fixer from

the paper.

o Ava ila b le f r o m: C h e m ica l s u p pli e rs .

S O D I U M T E T R A B O R A T E ( B O R A X ) Na

B

O

2

4

7

T he Sa l t p ri n t M a n u a l | A pp en dix 1 C he m ica ls 9 4

o A pp ea ra n ce: W h i te c r ys ta ll in e p o wd e r .

o Ha z a rd s: L o w ha za r d ris k b u t ca n be t oxi c i f si gn i fi ca n t a m o un ts a r e i n ha l ed , i n ge st e d o r m a ke c on ta c t wi t h sk in .

o O t he r n a mes : Bo r a x, bo ra t e o f s o da o r so d i u m,

te t ra b o ra te so d i u m bo ra t e , or di so d i u m te t ra bo ra t e .

o S ub s ti t u te : n on e .

o Uses: gold toning to render acidic gold chloride alkaline

o Ava ila b le f r o m: C h e m ica l s u p pli e rs , s u pe r ma r ke ts .

S O D I U M T H I O C Y A N A T E Na S C N

o A pp ea ra n ce: C ol o u rl ess o r wh i t e de li q ue scen t c r ys ta l s .

in ha la ti on ,

in g es ti on a n d s kin

o Ha z a rd s: Ha r m f ul b y

con ta c t . Con ta c t wi t h a ci d li be r a t es hi g hl y t oxi c ga s.

o O t he r n a m es : S od i u m r h od an at e an d s od iu m s ul fo c ya n i de .

o S ub s ti t u te : Potassium thiocyanate.

o Uses: Toning.

o Ava ila b le f r o m: C h e m ica l s u p pli e r .

S O D I U M T H I O S U L F A T E Na

S

O

. 5H

0

2

2

3

2

o A pp ea ra n ce: L a r ge t ra n s pa r en t c r ys ta ls , wh i t e p o wd e r .

o Ha z a rd s: Ey e i r ri ta n t , ca n de c o m po se re lea s in g t oxi c

su l p h u r d iox i de ga s .

o O t he r n a m es : H y po , s od i u m h yp os u lf i te .

o S ub s ti t u te : Ammonium thiosulfate.

o Uses: Known as fixer „hypo‟: dissolves the unexposed silver chloride, removing the light sensitivity of the salt print.

o Ava ila b le f r o m: C h e m ica l s u p pli e rs .

T he Sa l t p ri n t M a n u a l | 9 5

AP P E N D I X 2 M A T ER I AL S U P P L I ER S

C H E M I C A L S A N D A L TE R N A TI V E P R O C E S S K I T S

B O S T I C K & S U L L I V A N . P. O . Box 1 6 6 3 9 , Sa n ta Fe , 8 7 5 9 2, Ne w M exi co U SA Tel : 5 0 5 4 7 4 0 8 9 0 Web : ww w. b o s ti c k - s ul li va n . co m G O L D S TR E E T S TU D I O S 7 0 0 J a me s L a n e T re n t ha m Ea s t V i c to r ia 3 4 5 8 A us t ra l ia . Tel : 6 1 3 5 4 2 4 1 8 3 5 Web : ww w. g o ld s t ree ts t u di o .c o m .a u P H O T O G R A P H E R ‟ S F O R M U L A R Y I N C P. O . Box 9 5 0 C on do n M o n t a n a 5 9 8 2 6 U S A. Web : w w w. p h o t of o r m u la r y. c o m V A N B A R 5 3- 5 7 M un s te r T ce No r t h M el bo u rn e V i c to r ia 3 0 5 1 A us t ra li a . Tel 6 1 3 9 9 1 5 1 9 0 0 Web : ww w. v a n ba r. c o m.a u

E X P O S U R E F R AM E S:

G O L D S TR E E T S TU D I O S 7 0 0 J a me s L a n e T re n t ha m Ea s t V i c to r ia 3 4 5 8 A us t ra l ia . Tel : 6 1 3 5 4 2 4 1 8 3 5 Web : ww w. g o ld s t ree ts t u di o .c o m .a u

S H E E T F I L M:

F O R M A - B L A N O N E G R O . A U S T R A L I A . www. b l a n con e g ro . c o m.a u I L F O R D - P H O T O R E S O U R C E S . A U S T R A L I A . www. p h o t o re so u r ce s. co m .a u G L AS S R O D C H E M I C A L S P R E A D E R S:

G O L D S TR E E T S TU D I O S 7 0 0 J a me s L a n e T re n t ha m Ea s t V i c to r ia 3 4 5 8 A us t ra l ia . Tel : 6 1 3 5 4 2 4 1 8 3 5 Web : ww w. g o ld s t ree ts t u di o .c o m .a u

P AP E R S U P P L I E R S :

G O L D S TR E E T S TU D I O S

T he Sa l t p ri n t M a n u a l | A pp en dix 2 M a t er ia l s u p pl ie rs 9 6

7 0 0 J a me s L a n e T re n t ha m Ea s t V i c to r ia 3 4 5 8 A us t ra l ia . Tel : 6 1 3 5 4 2 4 1 8 3 5 Web : www. g o ld s t ree ts t u di o .c o m .a u N E I L ‟ S A R T S U P P L I E S / N E I L W A L L A C E P R I N T M A K I N G S U P P L I E S 4 4- 4 6 G ree ves S t r ee t , Fi t z ro y V i c t o ria A us t ra lia 3 0 6 5 Tel : 6 1 3 9 4 1 9 - 5 9 4 9 We b : ww w. e - a rt s to r e. co m .a u B O S T I C K & S U L L I V A N . P. O . Box 1 6 6 3 9 , Sa n ta Fe , 8 7 5 9 2, Ne w M exi co U SA Tel : 5 0 5 4 7 4 0 8 9 0 Web : w ww. b o s ti c k - s ul li va n . co m S TE P W E D G E S

S T O U F F E R I N D U S T R I E S w w w. s t o u ffe r .n e t

T he Sa l t p ri n t M a n u a l | A pp en dix 2 M a t er ia l s u p pl ie rs 9 7

B IB L I OG RA P H Y

A da ms , A . ( 1 9 9 4 ) T h e P r i n t, L i t t le , B r o wn a n d Co m pa n y ,

To r on to Ca n a da .

Cra wf o rd , W . ( 1 9 7 9 ) K ee p ers o f th e L ig h t , M o rga n & M o r ga n ,

In c. , Ne w Yo r k , U S A .

Ct ein ( 1 9 9 7 ) P o s t E x po s ur e - A d v a n ce Te c h n iq ues fo r t he

P ho to g r a p h i c P r i n te r, B u t te r wo r t h - Hein ema n n , W o b u rn M A U S A .

E.J .Wa l l a n d F. I .J o r d a n ( 1 9 7 5) P ho to gr a p h i c F a c ts a n d

Fo r m u l as , A m e ri ca n P h o t og r a pi c B o ok P u bl is h in g C o. , In c. , Ne w Yo r k U SA .

Ede r , J . M . ( 1 9 7 8 ) H i s to r y o f P ho to g r a ph y, D ov e r P u bl ic a ti on s

In c N e w Yo r k .

Ep h ra u m s, E . ( 1 9 9 5 ) Cr e a ti v e E l e me n ts , 2 1s t C en t u r y

P u bli s hin g L t d , L on don G r ea t B r i ta in .

Fa r be r , R . ( 1 9 9 8 ) H i s to r i c P ho to g r a p h ic P ro c es s es : A G u i d e t o

Cr e a t i ng H a n d m a d e Pho to g r a p h i c I m a ge s , A ll wo r t h P re ss , Ne w Yo r k .

Gra y , M . , O l l ma n , A . a n d M c C us ke r , C. ( 2 0 0 2 ) Th e Fi rs t

Pho to g r a p hs W i ll i a m H e nr y Fo x T a l bo t a n d th e B ir t h o f Pho to g r a p h y, Po we r Ho us e B oo k s U S A, N e w Yo r k .

H un t, R. ( 1 9 7 3) A M a n u a l o f P ho to gr a p h y, A rn o P res s In c . U SA .

H u tc h in g s, G . ( 1 9 9 2 ) T h e Bo o k o f P yro , Bi t te r D og P ress ,

Gra n i te Ba y, C A .

J a me s, C. ( 2 0 0 2) T h e Bo o k o f A l t er n a t i v e P ho to gr a p h i c

Pro ces s es , De l ma r , Ne w Yo r k .

Ken n e t h-M e es , C. E . a n d J a mes , T . H . ( 1 9 6 6 ) T h e T heo ry o f t h e

Pho to g r a p h i c P ro ces s , T he M a c mi lla n C o mp a n y, Ne w Yo r k .

L a m b , A . R . ( 1 9 9 9 ) F r a mi n g P ho to gr a p h y , Co l u m ba P u b lis h in g,

O h io , U S A.

L a ve d rin e , B. ( 2 0 0 3) A G u i de to t he Pr e v en t a t i ve Co ns e r v a ti o n

o f P ho to g r a p hi c Co l l ec t io ns , T he G e t ty C on se r va ti on In s t i t u te , L os An ge l es U S A.

Ne ls on , M . I . ( 2 0 0 4 ) Pre c is io n D i gi t a l N e ga t i ves : Fo r Si l ve r &

O th er A l t er n a t i ve Pr o ces s es , M a rk I Nel s on .

Rei ll y , J . M . ( 1 9 8 0 ) T he A l b u m e n & S a l te d P a pe r Bo o k : T he His to r y a n d pr a c t i c e o f p ho to gr a p h i c pr i n t i ng , 1 8 4 0 - 1 8 9 5 ., L ig h t I m p res sion s Co r p o ra ti on . , Ro c hes t e r, U SA .

T he Sa l t p ri n t M a n u a l | Bi b li og ra p h y 9 8

Sc ha a f , L . J . ( 1 9 9 6 ) R eco r ds o f t h e D aw n o f P h o t o gr a p h y

T a l bo t' s No te bo o ks P & Q , U n i ve rs it y P re ss Ca m b ri dg e, Ca mb r i dge G r ea t B r i ta i n .

Sc ha a f , L . J . ( 2 0 0 0 ) T he P ho to gr a p h i c Ar t o f Wi l l i a m H e nr y F o x

T a l bo t , P ri n c et on U n ive r si t y P r ess , O xf o rd s hi re , U K.

St r oe be l, L ., Co m p t on , J ., C u r r en t, I . a n d Z a kia , R . ( 1 9 8 6 ) P ho to g r a p h i c M a t er i a ls an d P ro ces s es , B u t te r wo r t h P u bli s he rs , S t on e ha m , M A , U S A .

T u rn e r , S. ( 1 9 9 8 ) T h e Bo o k o f F i ne P a p er s , T ha me s a n d H u ds on

In c, Ne w Yo r k .

Wa ll , E . J . a n d J o r da n , F. I . ( 1 9 7 5 ) P ho to gr a p h ic F a c ts a n d

Fo r m u l as , A m e ri ca n P h o t og ra p hi c Bo o k P u bli s hin g Co . , In c. , Ne w Yo r k U SA .

Wa ll s, H. J . a n d A t t r id ge , G. G . ( 1 9 7 7 ) B as i c P ho to S c ie n c e, ho w

p ho to g r a p hy w o r ks , Fo ca l P ress , L on d on .

Wa r e, M . ( 2 0 0 6 ) T he C hr ys o ty p e M a n u a l, T h e C ro m we l l P re ss

L t d, U K .

Wa r e, M . J . ( 1 9 9 4) M ec h a n is m o f I m a ge D e te rio r a t io n i n E ar l y

Pho to g r a p hs - t he s e ns i ti v i t y to Li g h t o f WH F T a l bo t' s h a l i de -f i xe d I m a ges 1 8 3 4 - 1 8 4 4 , S ci en ce M use u m a n d Na ti on a l M u se u m o f P h o t og ra p h y, F il m & Te le vis ion , B ra df o rd , L on d on .

Wa r e, M . J . ( 2 0 0 6. ) Go l d i n Ph o t o gr a p h y ., f fo t of fi l m p u b lis h in g ,

B ri g h ton , U K.

T he Sa l t p ri n t M a n u a l | Bi b li og ra p h y 9 9