Photoshop 6 for Windows Bible- P13

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Photoshop 6 for Windows Bible- P13:If you are reading this foreword, it probably means that you’ve purchased a copy of Adobe Photoshop 6.0, and for that I and the rest of the Photoshop team at Adobe thank you. If you own a previous edition of the Photoshop Bible, you probably know what to expect. If not, then get ready for an interesting trip.

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Chapter 8 ✦ Selections and Paths 329 32 (default) 60 100 Figure 8-6: Note the results of clicking on a pixel with a brightness value of 140 (top row) and a brightness value of 10 (bottom row) with the tolerance set to three different values. Red Green Blue Figure 8-7: Because the yellow Sasquatch sign contains almost no blue, it appears most clearly distinguished from its background in the blue channel. So the blue channel is the easiest channel in which to select the sign with the magic wand.
330 Part III ✦ Selections, Masks, and Filters Note Here’s one more twist to the Tolerance story: The magic wand is affected by the Sample Size option that you select for the eyedropper tool. If you select Point Sample, the wand bases its selection solely on the single pixel that you click. But if you select 3 by 3 Average or 5 by 5 Average, the wand takes into account 15 or 25 pixels, respectively. As you can imagine, this option can have a noticeable impact on the extent of the selection that you get from the wand. Try clicking the same spot in your image using each of these Sample Size settings, using the same Tolerance value throughout, to see what I mean. Making the wand see beyond a single layer The Use All Layers option enables you to create a selection based on pixels from different layers (see Chapter 12 for more about layers). Returning to my previous landmass example, suppose you set Europe on one layer and North America on the layer behind it so the two continents overlap. Normally, if you clicked inside Europe with the magic wand, it would select an area inside Europe without extending out into the area occupied by North America on the other layer. Because the wand doesn’t even see the contents of other layers, anything outside Europe is an empty void. We’re talking pre-Columbus Europe here. If you select Use All Layers, though, the situation changes. Suddenly, the wand can see all the layers you can see. If you click on Europe, and if North America and Europe contain similar colors, the wand selects across both shapes. Mind you, while the Use All Layers option enables the wand to consider pixels on different layers when creating a selection, it does not permit the wand to actually select images on two separate layers. Strange as this may sound, no selection tool can pull off this feat. Every one of the techniques explained in this chapter is appli- cable to only a single layer at a time. Use All Layers merely allows the wand to draw selection outlines that appear to encompass colors on many layers. What good is this? Well, suppose you want to apply an effect to both Europe and North America. With the help of Use All Layers, you can draw a selection outline that encompasses both continents. After you apply the effect to Europe, you can switch to the North America layer — the selection outline remains intact — and then reapply the effect. Ways to Change Selection Outlines If you don’t draw a selection outline correctly the first time, you have two options. You can either draw it again from scratch, which is a real bore, or you can change your botched selection outline, which is likely to be the more efficient solution.
Chapter 8 ✦ Selections and Paths 331 You can deselect a selection, add to a selection, subtract from a selection, and even select the stuff that’s not selected and deselect the stuff that is. (If this sounds like a load of nonsense, keep reading.) Quick changes Some methods of adjusting a selection outline are automatic: You choose a com- mand and you’re finished. The following list explains how a few commands — all members of the Select menu — work: ✦ Deselect (Ctrl+D): You can deselect the selected portion of an image in three ways. You can select a different portion of the image; click anywhere in the image window with the rectangular marquee tool, the elliptical marquee tool, or the lasso tool; or choose Select ➪ Deselect. Remember, though, when no part of an image is selected, the entire image is susceptible to your changes. If you apply a filter, choose a color-correction command, or use a paint tool, you affect every pixel of the foreground image. ✦ Reselect (Ctrl+Shift+D): If you accidentally deselect an image, you can retrieve the most recent selection outline by choosing Select ➪ Reselect. It’s a great func- tion that operates entirely independently of the Undo command and History palette, and it works even after performing a long string of selection-unrelated operations. (You can restore older selections from the History palette, but that usually means undoing operations along the way.) ✦ Inverse (Ctrl+Shift+I): Choose Select ➪ Inverse to reverse the selection. Photoshop deselects the portion of the image that was previously selected and selects the portion of the image that was not selected. This way, you can begin a selection by outlining the portion of the image you want to protect, rather than the portion you want to affect. Tip You can also access the Inverse and Deselect commands from a context-sensitive pop-up menu in the image window. Right-click to make the menu appear under- neath your cursor. Manually adding and subtracting Ready for some riddles? When editing a portrait, how do you select both eyes with- out affecting any other portion of the face? Answer: By drawing one selection and then tacking on a second selection. How do you select a doughnut and leave the hole behind? Answer: Encircle the doughnut with the elliptical marquee tool, and then use the same tool to subtract the center.
332 Part III ✦ Selections, Masks, and Filters Photoshop enables you to whittle away at a selection, add pieces on again, whittle away some more, ad infinitum, until you get it exactly right. Short of sheer laziness or frustration, no reason exists why you can’t eventually create the selection out- line of your dreams: ✦ Adding to a selection outline: To increase the area enclosed in an existing selection outline, Shift-drag with one of the marquee or lasso tools. You also can Shift-click with the magic wand tool or Shift-click with one of the marquee tools when the Fixed Size option is active (as described in the “Geometric selection outlines” section earlier in this chapter). ✦ Subtracting from a selection outline: To take a bite from an existing selection outline, press Alt while using one of the selection tools. ✦ Intersecting one selection outline with another: Another way to subtract from an existing selection outline is to Shift+Alt-drag around the selection with the rectangular marquee, elliptical marquee, or lasso tool. You also can Shift+Alt-click with the magic wand tool. Shift+Alt-dragging instructs Photoshop to retain only the portion of an existing selection that also falls inside the new selection outline. I frequently use this technique to confine a selection within a rectangular or elliptical border. Photoshop 6 If the key-press techniques seem bothersome, use the selection state buttons at the left end of the Options bar to set your selection tool to add, subtract, or intersect mode. (Figure 8-8 labels the icons.) After clicking a button, simply drag to alter the selection outline. To toggle the tool back to normal operating mode, click the first button in the bunch. Note that the keyboard techniques described in the preceding list work no matter what button you select in the Options bar. For example, if you click the Intersect icon, Alt-dragging still subtracts from the selection outline. Normal Add Subtract Intersect Figure 8-8: You can use the selection state buttons as well as the Shift and Alt keys when modifying a selection outline. Tip When you’re working with the magic wand, you can right-click to display a context- sensitive menu that contains the add, subtract, and intersect mode options. Click the mode you want to use.
Chapter 8 ✦ Selections and Paths 333 Tip Photoshop displays special cursors to help you keep track of a tool’s selection state. Suppose that you select part of an image and the lasso tool is active. When you press Shift or click the Add button on the Options bar, Photoshop appends a little plus sign to the lasso cursor to show you’re about to add. A minus sign indi- cates that you’re set to subtract from the selection outline; a multiply sign appears when you work in intersect mode. If you’re pressing keys to switch tool modes, Photoshop temporarily selects the corresponding selection state button on the Options bar as well. Using Shift and Alt like a pro The roles of the Shift and Alt keys in adding, subtracting, and intersecting selection outlines can interfere with your ability to take advantage of other functions of the selection tools. For example, when no portion of an image is selected, you can Shift- drag with the rectangular marquee tool to draw a square. But after a selection is active, Shift-dragging adds a rectangle — not a square — to the selection outline. Photoshop 6 This is one reason why Adobe added the selection state buttons to the Options bar. After you click a button, the tool adds, subtracts, or intersects, with no additional key presses on your part, depending on which button you click. But if you want to hide the Options bar or you just prefer pressing keys to clicking buttons, you can control the selection tools from the keyboard without giving up any selection flexibility. The trick is to learn when to press Shift and Alt. Sometimes you have to press the key before you begin your drag; other times you must press the key after you begin the drag but before you release. For example, to add a square to a selection outline, Shift-drag, release Shift while keeping the mouse button pressed, and press Shift again to snap the rectangle to a square. The same goes for adding a circle with the elliptical marquee tool. The following list introduces you to a few other techniques. They sound pretty elaborate, I admit, but with a little practice, they become second nature (so does tightrope walking, but don’t let that worry you). Before you try any of them, be sure to select Normal from the Style pop-up menu on the Options bar. ✦ To subtract a square or a circle from a selection, Alt-drag, release Alt, press Shift, drag until you get it right, release the mouse button, and then release Shift. ✦ To add a rectangle or an ellipse by drawing from the center outward, Shift- drag, release Shift, press Alt, and hold Alt until after you release the mouse button. You can even press the spacebar during the drag to move the mar- quee around, if you like. ✦ To subtract a marquee drawn from the center outward, Alt-drag, release Alt, press Alt again, and hold the key down until after you release. ✦ What about drawing a straight-sided selection with the lasso tool? To add a straight-sided area to an existing selection, Shift-drag with the tool for a short distance. With the mouse button still down, release Shift and press Alt. Then click around as you normally would, while keeping the Alt key down.
334 Part III ✦ Selections, Masks, and Filters ✦ To subtract a straight-sided area, Alt-drag with the lasso, release Alt, press Alt again, and click around with the tool. If you can’t manage the last two lasso-tool techniques, switch to the polygonal lasso instead. In fact, the reason Adobe provided the polygonal lasso tool was to accom- modate folks who don’t want to deal with pressing Alt seven times during a single drag (which I strangely quite enjoy). Adding and subtracting by command Photoshop provides several commands under the Select menu that automatically increase or decrease the number of selected pixels in an image according to numer- ical specifications. The commands in the Select ➪ Modify submenu work as follows: ✦ Border: This command selects an area of a specified thickness around the perimeter of the current selection outline and deselects the rest of the selec- tion. For example, to select a 6-point-thick border around the current selec- tion, choose Select ➪ Modify ➪ Border, enter 6 in the Width option box, and press Enter. But what’s the point? After all, if you want to create an outline around a selection, you can accomplish this in fewer steps by choosing Edit ➪ Stroke. The Border command, however, broadens your range of options. You can apply a special effect to the border, move the border to a new location, or even create a double-outline effect by first applying Select ➪ Modify ➪ Border and then applying Edit ➪ Stroke. ✦ Smooth: This command rounds off the sharp corners and weird anomalies in the outline of a selection. When you choose Select ➪ Modify ➪ Smooth, the program asks you to enter a Sample Radius value. Photoshop smoothes out corners by drawing little circles around them; the Sample Radius value deter- mines the radius of these circles. Larger values result in smoother corners. Tip The Smooth command is especially useful in combination with the magic wand. After you draw one of those weird, scraggly selection outlines with the wand tool, use Select ➪ Modify ➪ Smooth to smooth out the rough edges. ✦ Expand and Contract: Both of these commands do exactly what they say, either expanding or contracting the selected area by a specified amount. For example, if you want an elliptical selection to grow by 8 pixels, choose Select ➪ Modify ➪ Expand, enter 8, and call it a day. These are extremely useful commands; I refer to them several times throughout the book. Photoshop 6 Photoshop 6 enables you to expand and contract selections by as many as 100 pixels, up from the previous limit of 16. The upper limits of the Border and Smooth commands were raised also (to 200 and 100 pixels, respectively), but my guess is that you’ll have less reason to take advantage of those changes than you will the new ranges for Expand and Contract.
Chapter 8 ✦ Selections and Paths 335 Tip Both Expand and Contract have a flattening effect on a selection. To round things off, apply the Smooth command with a Sample Radius value equal to the number you just entered into the Expand Selection or Contract Selection dialog box. You end up with a pretty vague selection outline, but what do you expect from automated commands? In addition to the Expand command, Photoshop provides two other commands — Grow and Similar — that increase the area covered by a selection outline. Both com- mands resemble the magic wand tool because they measure the range of eligible pix- els by way of a Tolerance value. In fact, the commands rely on the same Tolerance value (on the Options bar) that you set for the magic wand. So if you want to adjust the impact of either command, you must first select the magic wand and then apply the commands: ✦ Grow: Choose Select ➪ Grow to select all pixels that both neighbor an existing selection and resemble the colors included in the selection, in accordance with the Tolerance value. In other words, Select ➪ Grow is the command equivalent of the magic wand tool. If you feel constrained because you can only click one pixel at a time with the magic wand tool, you may prefer to select a small group of representative pixels with a marquee tool and then choose Select ➪ Grow to initiate the wand’s magic. ✦ Similar: Another member of the Select menu, Similar works like Grow, except the pixels needn’t be adjacent. When you choose Select ➪ Similar, Photoshop selects any pixel that falls within the tolerance range, regardless of the loca- tion of the pixel in the foreground image. Note Although both Grow and Similar respect the magic wand’s Tolerance value, they pay no attention to the other wand options — Contiguous, Use All Layers, and Anti- aliased. Grow always selects contiguous regions only; Similar selects noncontigu- ous areas. Neither can see beyond the active layer or produce antialiased selection outlines. One of the best applications for the Similar command is to isolate a complicated image set against a consistent background whose colors are significantly lighter or darker than the image. Consider Figure 8-9, which features a dark and ridiculously complex foreground image set against a continuous background of medium-to-light brightness values. The following steps explain how to separate this image using the Similar command in combination with a few other techniques I’ve described thus far. STEPS: Isolating a Complex Image Set Against a Plain Background 1. Use the rectangular marquee tool to select some representative portions of the background. In Figure 8-9, I selected the lightest and darkest portions of the background along with some representative shades in between. Remember, you make multiple selections by Shift-dragging with the tool.
336 Part III ✦ Selections, Masks, and Filters Figure 8-9: Before choosing Select ➪ Similar, select a few sample portions of the background for Photoshop to base its selection range. 2. Double-click the magic wand tool icon to display the Tolerance option box on the Options bar. For my image, I entered a Tolerance value of 16, a rela- tively low value, in keeping with the consistency of the background. If your background is less homogenous, you may want to enter a higher value. Make certain you turn on the Anti-aliased check box. 3. Choose Select ➪ Similar. Photoshop should select the entire background. If Photoshop fails to select all the background, choose Edit ➪ Undo (Ctrl+Z) and use the rectangular marquee tool to select more portions of the background. You may also want to increase the magic wand’s Tolerance value. If Photoshop’s selection bleeds into the foreground image, try reducing the Tolerance value. 4. Choose Select ➪ Inverse. Or press Ctrl+Shift+I. Photoshop selects the fore- ground image and deselects the background. 5. Modify the selection as desired. If the detail you want to select represents only a fraction of the entire image, Shift+Alt-drag around the portion of the image you want to retain using the lasso tool. In Figure 8-10, I Shift+Alt- dragged with the polygonal lasso tool to draw a straight-sided outline around the selection. 6. Congratulations, you’ve isolated your complex image. Now you can filter your image, colorize it, or perform whatever operation inspired you to select this image in the first place. I wanted to superimpose the image onto a differ- ent background, so I copied the image to the Clipboard (Ctrl+C), opened the desired background image, and then pasted the first image into place (Ctrl+V). The result, shown in Figure 8-11, still needs some touching up with the paint and edit tools, but it’s not half bad for an automated selection process.
Chapter 8 ✦ Selections and Paths 337 Figure 8-10: Shift+Alt-drag with the polygonal lasso tool to intersect the area you want to select with a straight-sided outline. Figure 8-11: The completed selection superimposed onto a new background.
338 Part III ✦ Selections, Masks, and Filters Note Whenever you introduce a selection into another image — by copying and pasting or by dragging the selection and dropping it into another image window — Photoshop automatically assigns the selection to a new layer. This is a great safety mechanism because it prevents you from permanently affixing the selection to its new back- ground. But it also limits your file format options when saving an image; you can’t save in a format other than the native Photoshop format, PDF, or TIFF (the last two now offer layer support) without first flattening the image. For the big story on lay- ers, read Chapter 12. Softening selection outlines You can soften a selection in two ways. The first method is antialiasing, introduced in Chapter 5. Antialiasing is an intelligent and automatic softening algorithm that mimics the appearance of edges you’d expect to see in a sharply focused photograph. Note Where did the term antialias originate? Anytime you try to fit the digital equivalent of a square peg into a round hole — say, by printing a high-resolution image to a low-resolution printer — the data gets revised during the process. This revised data, called an alias, is frequently inaccurate and undesirable. Antialiasing is the act of revising the data ahead of time, essentially rounding off the square peg so it looks nice as it goes into the hole. According to a reader who spent time at MIT’s Architecture Machine Group, “We did the first work with displaying smooth lines. We called the harsh transitions jaggies and the display process dejaggying. Somehow, this easy-to-understand term slid sideways into ‘alias’ (which it isn’t, really, but it’s too late to change).” Now you know. When you draw an antialiased selection outline in Photoshop, the program calcu- lates the hard-edged selection at twice its actual size. The program then shrinks the selection in half using bicubic interpolation (described in Chapter 2). The result is a crisp image with no visible jagged edges. The second softening method, feathering, is more dramatic. Feathering gradually dissipates the selection outline, giving it a blurry edge. Photoshop accommodates partially selected pixels; feathering fades the selection both inward and outward from the original edge. You can specify the number of pixels affected either before or after drawing a selec- tion. To feather a selection before you draw it with a marquee or lasso tool, enter a value in the Feather option box, found on the Options bar in Photoshop 6. To feather a selection after drawing it, choose Select ➪ Feather or press Ctrl+Alt+D. You also can right-click in the image window and then choose Feather from the pop-up menu that appears next to your cursor. The Feather Radius value determines the approximate distance over which Photoshop fades a selection, measured in pixels in both directions from the original selection out- line. Figure 8-12 shows three selections lifted from the image at the bottom of the figure.
Chapter 8 ✦ Selections and Paths 339 The first selection is antialiased only. I feathered the second and third selections, assigning Feather Radius values of 4 and 12, respectively. As you can see, a small feather radius makes a selection appear fuzzy; a larger radius makes it fade into view. Figure 8-12: Three clones selected with the elliptical marquee tool. The top image is antialiased and not feathered, the next is feathered with a radius of 4 pixels, and the third is feathered with a radius of 12 pixels.
340 Part III ✦ Selections, Masks, and Filters The math behind the feather A few eagle-eyed readers have written to ask me why feathering blurs a selection outline more than the number of pixels stated in the Feather Radius value. A radius of 4 pixels actually affects a total of 20 pixels: 10 inward and 10 outward. The reason revolves around Photoshop’s use of a mathematical routine called the Gaussian bell curve, which exaggerates the distance over which the selection outline is blurred. Figure 8-13 demonstrates the math visually. The top-left image shows a hard-edged elliptical selection filled with white against a black background. To its right is a side view of the ellipse, in which black pixels are short and white pixels are tall. (Okay, so it’s really a graph, but I didn’t want to scare you.) Because no gray pixels are in the ellipse, the side view has sharp vertical walls. The bottom-left image shows what happens if I first feather the selection with a radius of 4 pixels and then fill it with white. The side view now graphs a range of gray values, which taper gradually from black to white. See those gray areas on the sides (each labeled Diameter)? Those are the pixels that fall into the 8-pixel diame- ter, measured 4 pixels in and out from the original selection outline. These gray areas slope in straight lines. Top views Side views White Black White Black Diameter Diameter Figure 8-13: Here are some graphic demonstrations of what happens when you feather a selection. Photoshop tapers the ends of the feathered selections (shown by the black areas, bottom right) to prevent your eye from easily detecting where the feathering starts and stops.
Chapter 8 ✦ Selections and Paths 341 The rounded areas of the side view — painted black — are the Gaussian bell curves. These are appended to the radius of the feather to ensure smooth transitions between the blurry edges and the selected and deselected pixels. Programs that do not include these extra Gaussian curves end up producing ugly feathered selections that appear to have sharp, incongruous edges. Tip If exact space is an issue, you can count on the Feather command affecting about 2.7 times as many pixels as you enter into the Feather Radius option box, both in and out from the selection. That’s a total of 5.4 times as many pixels as the radius in all. If this was more than you wanted to know, cast it from your mind. Feathering makes the edges of a selection fuzzy — ’nuff said. Putting feathering to use You can use feathering to remove an element from an image while leaving the back- ground intact, a process described in the following steps. The image described in these steps, shown in Figure 8-14, is a NASA photo of a satellite with the Earth in the background. I wanted to use this background with another image, but to do so I first had to eliminate that satellite. By feathering and cloning a selection outline, I cov- ered the satellite with a patch so seamless you’d swear the satellite was never there. STEPS: Removing an Element from an Image 1. Draw a selection around the element using the lasso tool. The selection needn’t be an exact fit; in fact, you want it rather loose, so allow a buffer zone of at least 6 pixels between the edges of the image and the selection outline. Figure 8-14: Your mission, if you choose to accept it, is to remove the satellite by covering it with selections cloned from the background.
342 Part III ✦ Selections, Masks, and Filters 2. Drag the selection outline over a patch in the image. Now that you’ve specified the element you want to remove, you must find a patch, that is, some portion of the image to cover the element in a manner that matches the surrounding back- ground. In Figure 8-15, the best match seemed an area just below and to the right of the satellite. To select this area, move the selection outline independently of the image merely by dragging it with the lasso tool. (Dragging a selection with a selection tool moves the outline without affecting the pixels.) Make certain you allow some space between the selection outline and the element you’re trying to cover. Figure 8-15: After drawing a loose outline around the satellite with the lasso tool, I dragged the outline to select a portion of the background. 3. Choose Select ➪ Feather. Or press Ctrl+Alt+D. Enter a small value (8 or less) in the Feather Radius option box — just enough to make the edges fuzzy. (I entered 3.) Then press Enter to initiate the operation. 4. Clone the patch onto the area you want to cover. Select the move tool by pressing V. Then Alt-drag the feathered selection to clone the patch and posi- tion it over the element you want to cover, as shown in Figure 8-16. To align the patch correctly, choose Select ➪ Hide Extras (Ctrl+H) to hide the marching ants and then nudge the patch into position with the arrow keys. 5. Repeat as desired. My patch was only partially successful. The upper-left cor- ner of the selection matches clouds in the background, but the lower-right corner is dark and cloudless, an obvious rift in the visual continuity of the image. The solution: Try again. With the lasso tool, I drew a loose outline around the dark portion of the image and dragged it up and to the left as shown in Figure 8-17.
Chapter 8 ✦ Selections and Paths 343 Figure 8-16: Next, I used the move tool to Alt-drag the feathered selection over the satellite. Sadly, the patch was imperfect and required further adjustments. Figure 8-17: I used the lasso tool to draw a new outline around the dark, cloudless portion of the patch. Then I dragged the outline to a different spot in the background.
344 Part III ✦ Selections, Masks, and Filters 6. It’s all déjà vu from here. I chose Select ➪ Feather, entered 6 in the Feather Radius option box — thus allowing the clouds a sufficient range to taper off — and pressed Enter. I then selected the move tool and Alt-dragged the feath- ered patch over the dark, cloudless rift. Finally, I nudged, nudged, nudged with the arrow keys, and voilà, no more satellite. Figure 8-18 shows $200 mil- lion worth of hardware vaporized in less than five minutes. Figure 8-18: I selected a new bit of cloudy sky and placed it over the formerly cloudless portion of the patch. Satellite? What satellite? Moving and Duplicating Selections In the preceding steps, I mentioned that you can move either the selected pixels or the empty selection outline to a new location. Now it’s time to examine these tech- niques in greater depth. The role of the move tool To move selected pixels, you have to use the move tool. No longer is it acceptable merely to drag inside the selection with the marquee, lasso, or wand tool, as it was in Photoshop 3 and earlier. If you haven’t gotten used to it yet, now is as good a time as any. The move tool is here to stay. You can select the move tool at any time by pressing V (for mooV). The advantage of using the move tool is that there’s no chance of deselecting an image or harming the selection outline. Drag inside the selected area to move the selection; drag out- side the selection to move the entire layer, selection included. I explain layers in more detail in Chapter 12.
Chapter 8 ✦ Selections and Paths 345 Tip To access the move tool on a temporary basis, press and hold Ctrl. The move tool remains active as long as you hold Ctrl. This shortcut works when any tool except the hand, pen, or any shape or slice tool is active. Assign this shortcut to memory at your earliest convenience. Believe me, you spend a lot of time Ctrl-dragging in Photoshop. Making precise movements Photoshop provides three methods for moving selections in prescribed increments. In each case, the move tool is active, unless otherwise indicated: ✦ First, you can nudge a selection in 1-pixel increments by pressing an arrow key on the keyboard or nudge in 10-pixel increments by pressing Shift with an arrow key. This technique is useful for making precise adjustments to the position of an image. Tip To nudge a selected area when the move tool is not active, press Ctrl with an arrow key. Press Ctrl+Shift with an arrow key to move in 10-pixel increments. After the selection is floating — that is, after your first nudge — you can let up on the Ctrl key and use only the arrows (assuming a selection tool is active). ✦ Second, you can press Shift during a drag to constrain a move to a 45-degree direction — that is, horizontally, vertically, or diagonally. ✦ And third, you can use the Info palette to track your movements and to help locate a precise position in the image. To display the Info palette, shown in Figure 8-19, choose Window ➪ Show Info or press F8. The first section of the Info palette displays the color values of the image area beneath your cursor. When you move a selection, the other eight items in the palette monitor movement, as follows: ✦ X, Y: These values show the coordinate position of your cursor. The distance is measured from the upper-left corner of the image in the current unit of mea- sure. The unit of measure in Figure 8-19 is pixels. ✦ ∆X, ∆Y: These values indicate the distance of your move as measured hori- zontally and vertically. ✦ A, D: The A and D values reflect the angle and direct distance of your drag. ✦ W, H: These values reflect the width and height of your selection.
346 Part III ✦ Selections, Masks, and Filters Figure 8-19: The Info palette provides a world of numerical feedback when you move a selection. Cloning a selection When you move a selection, you leave a hole in your image in the background color, as shown in the top half of Figure 8-20. If you prefer to leave the original in place during a move, you have to clone the selection — that is, create a copy of the selec- tion without upsetting the contents of the Clipboard. Photoshop offers several ways to clone a selection: ✦ Alt-dragging: When the move tool is active, press Alt and drag a selection to clone it. The bottom half of Figure 8-20 shows a selection I Alt-dragged three times. (Between clonings, I changed the gray level of each selection to set them apart a little more clearly.) ✦ Ctrl+Alt-dragging: If some tool other than the move tool is active, Ctrl+Alt- drag the selection to clone it. This is probably the technique you’ll end up using most often. ✦ Alt+arrowing: When the move tool is active, press Alt in combination with one of the arrow keys to clone the selection and nudge it one pixel away from the original. If you want to move the image multiple pixels, press Alt+arrow the first time only. Then nudge the clone using the arrow key alone. Otherwise, you’ll create a bunch of clones, which can be a pain in the neck to undo. ✦ Ctrl+Alt+arrowing: If some other tool is active, press Ctrl and Alt with an arrow key. Again, press only Alt the first time, unless you want to create a string of clones. ✦ Drag-and-drop: Like about every other program on the planet, Photoshop lets you clone a selection between documents by dragging it with the move tool from one open window and dropping it in another, as demonstrated in Figure 8-21. As long as you manage to drop into the second window, the original image remains intact and selected in the first window. My advice: Don’t worry about exact positioning during a drag-and-drop; first get it into the second window and then worry about placement.
Chapter 8 ✦ Selections and Paths 347 Figure 8-20: When you move a selection, you leave a gaping hole in the selection’s wake (top). When you clone an image, you leave a copy of the selection behind. To illustrate this point, I cloned the selection in the bottom image three times. Cross- You can drag-and-drop multiple layers if you link the layers first. For more Reference information on this subject, see Chapter 12. ✦ Shift-drop: If the two images are exactly the same size — pixel for pixel — press Shift when dropping the selection to position it in the same spot it occupied in the original image. This is called registering the selection.
348 Part III ✦ Selections, Masks, and Filters Figure 8-21: Use the move tool to drag a selection from one open window and drop it into another (top). This creates a clone of the selection in the receiving window (bottom).