Photoshop cs5 missing manual_8

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  1. Printing on an Inkjet Printer 16. Turn on the Gamut Warning checkbox to make any out-of-gamut pixels appear gray in the preview area of your Print dialog box. You can ask Photoshop to show you a proof of any colors in your image that are out of gamut (meaning they’re unprintable) for the printer and paper you’ve selected. When you’re printing to expanded-gamut printers, you’ll encounter far fewer out-of-gamut colors than you would with a standard CMYK printing press. Adobe improved Photoshop’s soft-proofing accuracy in CS4, so the pre- view should give you a good sense of what your print will look like. Of course, none of this means diddly unless you’ve calibrated your monitor so you see reli- able results (see page 667). 17. Glance over your settings in the Print dialog box one last time and, if they’re okay, click the Print button. After all that hard work, you see the fruit of your labors in the form of a glori- ously accurate, high-quality print. Yippee! Note: In CS4 and earlier, you encountered the Print Settings dialog box after clicking the Print button. In CS5, the settings from the Page Setup dialog box and the Print Settings dialog box have been combined into the Print dialog box, meaning you’ve got one less dialog box to deal with before hearing the pitter patter of your printer actually printing. poWeR USeRS’ CLINIC Printing Vectors and 16-bit Images or diagnostic page that lists which technologies the If your image contains vectors or 16-bit images (page 45), printer works with.) If your printer is a PostScript the Print dialog box contains yet another set of printing op- printer, you can preserve the wonderfully crisp edges tions you need to worry about: of your vectors by turning on this checkbox. If it’s • Include Vector Data. Choose Output from the pop- grayed out, your image doesn’t include any vector up menu at the top right of the Print dialog box and info so you don’t have to worry about it. you’ll see this checkbox. If your image contains vec- • Send 16-bit Data. In CS4 this option was one of the tor artwork (Chapter 13) or Type layers (Chapter 14), Output settings discussed above, but in CS5 it lives you need to print them with a PostScript printer (like beneath the Print Settings button (see Figure 16-6, some laser and inkjet printers). If you’re printing to a top). If your image contains 16-bit pixel info, Pho- non-PostScript printer (like most inkjets), you should toshop lets you print all 16 bits of it; that is, if your rasterize (page 110) your vectors first so you can see printer can handle it (the checkbox is grayed out if how they’ll look before you actually print them. (If you it can’t). To make sure the extra info is sent to your don’t know whether your printer supports PostScript, printer, turn on this checkbox. check your owner’s manual or print a specification chapter 16: photoshop and print 683
  2. Printing on a Commercial Offset Press Printing on a Commercial Offset Press If you prepare artwork for stuff that’s printed using a commercial offset printing press (magazines, product packaging, newspapers, and so on), you’ve got loads more to worry about than if you’re sending your image to an inkjet printer. Unlike printing to an inkjet printer, where your images gets converted from RGB to CMYK during the printing process, a commercial offset press usually requires you to convert your image to CMYK before it’s printed. In this section, you’ll learn the very specific steps you need to follow to preserve your image’s color when you convert it to CMYK. But before you dive too deeply into color-mode conversion, you need to understand a bit more about how offset presses work. Note: Inkjet printers spray their ink from a print head directly onto a page. An offset press, however, transfers, or offsets, ink from an image on a plate onto a rubber blanket and then onto a page—which is why commercial printing presses are called “offset presses.” Commercial offset presses are huge, noisy, ink-filled metal beasts. As you learned back in Chapter 5 (page 195), they split your image’s four CMYK channels into indi- vidual color separations, which are loaded onto big cylinders aligned so that all four colors are printed, one on top of another, to form your final image. If the cylinders aren’t aligned properly, you’ll see faint traces of one or more colors peeking outside the edges of your image, making it look blurry (this blurriness is called being “out of registration”). Instead of the dyes used by inkjet printers, commercial offset presses use two types of ink: process and spot. Process inks include cyan, magenta, yellow, and black (CMYK), and they’re printed as overlapping patterns of halftone dots (Figure 16-9, left) that let you economically reproduce the wide range of colors found in continuous-tone images like photos (Figure 16-9, right). Spot inks, on the other hand, are used to match very specific color requirements (like a color in a corporate logo—the official UPS brown, for example), and they’re printed on a separate cylinder on the press. More spot colors mean more cylinders and therefore more separations, which translates into higher printing costs. Since it’s easy to get hit with unexpected costs when you’re sending out a print job, you need to make darn sure you know exactly how many colors it’ll take to print your image (most print jobs involving color photos use only the four process colors). You’ll learn all about spot colors later in this chapter. Photoshop cs5: The Missing Manual 684
  3. Printing on a Commercial Offset Press Figure 16-9: Left: If you look closely at an image printed on a press, you can see the dots it’s made from. The next time you pick up a magazine or newspaper, stick it right up to your nose and you’ll see ’em. To keep the dots from printing on top of each other, they’re printed at specific angles according to ink color. Right: Images that contain a wide range of smooth colors are called continuous- tone images, like this beautiful photo by Taz Tally (www.taz tallyphotography. com). Finally, unlike sending an image straight from Photoshop to your inkjet printer, you’ll rarely (if ever) send a single image to an offset press. Instead, you place your image in a page-layout document (like one made with Adobe InDesign) that con- tains other images, along with text (referred to in geek circles as copy), and that’s what you send to the printing company. You need to make sure your images have the right print dimensions and resolution (discussed on page 669) and that they’re in the right color mode before you place your image in InDesign. The following pages explain how to do that as painlessly as possible. Converting RGB Images to CMYK Using Built-In Profiles First and foremost, you need to know who’s handling the conversion from RGB to CMYK. Historically, printing companies have requested (required!) you to convert images yourself but this is slowly changing, particularly with the increased use of digital presses (see page 705). If you have no idea whether you’re supposed to convert the RGB to CMYK yourself or if you want to know whether the printing company has a custom profile you can use for the conversion, pick up the phone. Communication is crucial in situations like this because if your print job hits the press at 2:00 a.m., it’ll be your phone that rings if there’s a problem. This is one call you’re better off making than receiving. chapter 16: photoshop and print 685
  4. Printing on a Commercial Offset Press If you have to convert the color mode yourself, it’s important to choose the proper CMYK color printer and paper profile. You can do it in a couple of ways, but the fol- lowing steps will lead you down a simple and foolproof path: 1. Open your RGB image and duplicate it. Choose Image➝Duplicate to create a new copy of your image to guarantee that you won’t accidentally save over your original RGB image. 2. Name your new image and save it as a TIFF file. Choose File➝Save or press �-S (Ctrl+S on a PC) and then give it a name. (It’s a good idea to include the file’s color mode in the name so you can see at a glance which mode it’s in.) Choose TIFF from the Format pop-up menu at the bottom of the Save dialog box and then click Save. 3. Choose Edit➝“Convert to Profile”. In the Conversion Options section of the dialog box that appears (see Figure 16-10), set the Engine menu to “Adobe (ACE)” and the Intent menu to Perceptual. Also, turn on the Use Black Point Compensation checkbox. Figure 16-10: Don’t panic when you see the Profile pop-up menu. These super funky names are simply the various color profiles you can use to convert RGB to CMYK. As you learned at the beginning of this chapter, there are a bazillion printers, papers, and colorants (inks, dyes, toners) out there, so this long list merely reflects that diversity. 4. From the Destination Space’s Profile pop-up menu (Figure 16-10), choose a profile that reflects the type of ink, press, and paper your printing company will use to print the image. You can think of this menu as a printer profile menu. If you can’t find a custom profile (see the next section), hunt for a profile that matches the ink, press, and paper for your current print job. If your image is being printed in North Amer- ica on a sheetfed printing press using coated paper stock, for example, you can pick the tried-and-true “U.S. Sheetfed Coated v2” profile. A newer commercial sheetfed profile that also might work is “Coated GRACoL 2006”. But before you guess, ask your printing company what profile it wants you to use. Photoshop cs5: The Missing Manual 686
  5. Printing on a Commercial Offset Press 5. Click OK to complete the color conversion process and save your image. Press �-S (Ctrl+S) to save your image in the new color mode. After you save your CMYK image, you’re ready to place it in your page-layout docu- ment. Because you wisely duplicated your image in step 1, you’ve still got the original, full-color RGB image to go back to if you ever need to edit it. Sweet! Custom RGB to CMYK Profile Conversions If your printing company has painstakingly created its own custom color profile, you’re much better off using it than one of the built-ins. The process is similar to the one explained in the previous section, but you need to install the custom profile (as explained on page 667) before you can use it. Once you’ve downloaded it, follow these steps to put it to use: 1. Locate the appropriate profile folder on your hard drive. Figuring out where to store the profile is your biggest challenge since different operating systems and different versions of Photoshop store profiles in different places. On a Mac running OS X 10.5 or later, you can find the main color pro- files folder in Computer/Library/Application Support/Adobe/Color/Profiles. If you have a Windows computer, look in Users\Profiles and Windows\System32\ Spool\Drivers\Color. However, you can always search for a folder named pro- files, or better yet, call your printing company and ask them where the folder for your particular operating system lives. Note: If your computer uses Windows, you can use the Color Management Control Panel to add and remove profiles. 2. Copy the custom profile to the Profiles folder described in the previous step. Figure 16-11 shows a profile named “MwHwkCC98_28#txt_CMYK_o_PCG. icc”. The name indicates that this profile was made using a 28-pound Mohawk text stock paper. Printing companies that have embraced color management have CMYK color profiles for a variety of paper stocks, so be sure you load the one for the paper you’re printing on by dragging the file into the folder. 3. Open your image, duplicate it, and save it as a TIFF file. To duplicate your image, choose Image➝Duplicate and then choose File➝Save or press �-S (Ctrl+S on a PC) and give the copy a name. Pick TIFF from the Format pop-up menu at the bottom of the Save dialog box and then click Save. chapter 16: photoshop and print 687
  6. Printing on a Commercial Offset Press Figure 16-11: Top: The toughest part of using a custom profile is figuring out where the heck to put it! Fortunately, on a Mac, the folder is named Profiles (shown here). Bottom: If you’re using a custom profile, the printing company may also want you to change other settings in the Print dialog box. For example, they might have you select Relative Colorimetric rather than Perceptual from the Intent menu. But you won’t know unless you ask ’em. 4. Choose Edit➝“Convert to Profile” and, in the resulting dialog box, choose your new profile from the Profile pop-up menu. If you don’t see the right profile in the list, you may need to restart Photoshop. In that case, press �-Q (Ctrl+Q) to quit the program and then double-click your image file to relaunch the program. 5. Change the Conversion Options settings if you need to. Ask the printing company if you need to adjust any settings in the Conversion Options section of the “Convert to Profile” dialog box. 6. To save your image, click OK and then press �-S (Ctrl+S). You’ve just completed your first custom CMYK conversion. Using Spot Color As mentioned earlier, commercial printing presses sometimes use special premixed custom inks called spot colors. If you’re a graphic designer working in prepress (the department that preps files for printing), the info that lies ahead is really important. If you’re a photographer or Web designer, save your brainpower and skip this part. Really. Photoshop cs5: The Missing Manual 688
  7. Printing on a Commercial Offset Press Photoshop wizard Ben Willmore (www.DigitalMastery.com) has come up with a great analogy to explain spot colors. Remember the box of crayons you used as a kid? A small box had 8 basic colors like blue, orange, and yellow. And then there was the big box of 64—with a sharpener on the back!—that had special colors like corn- flower, melon, and thistle. No matter how hard you tried, you couldn’t reproduce the special colors with a box of 8 crayons. In Photoshop, you can think of those special colors as spot colors and the box of 8 crayons as the CMYK color mode. Because of the impurity and variety of CMYK inks, they can’t produce all the col- ors you see in RGB mode (just like you can’t reproduce, say, cornflower from those original 8 crayons). If you happen to be tooling around in the Color Picker (page 493) and choose a color that can’t be produced in CMYK, Photoshop places a little gray warning triangle next to it (see Figure 16-12). This triangle is known as an out- of-gamut warning (gamut, as you learned earlier, means the full range of colors). If you click the triangle (or the tiny, square color swatch below it), Photoshop will change your color to the closest possible match that can be printed with CMYK inks. Figure 16-12: Top: If you pick a color that can’t be produced with CMYK inks, a little warning triangle appears next to the color swatch (circled). Click the triangle or the tiny square of color below it to make Photoshop pick the next best color. Bottom: In most cases, you can’t see any difference between the original color and the new one, but if you check your cursor’s location in the color field (circled), you can see that Photoshop moved it slightly. chapter 16: photoshop and print 689
  8. Printing on a Commercial Offset Press In some cases, the closest color match is close enough, but spot-color ink comes in handy in certain situations, like when you need: • To reduce printing costs. As you learned earlier, the more colors you use, the more cylinders and separations you need and the more the job will cost. If you print an image in black and one or two spot colors, you can reduce your print- ing costs because you’ll be using two or three separations instead of four. This technique is commonly used with line art (illustrations or outline drawings like those in a coloring book), though you can also use it for photos (see page 684). • To ensure color accuracy. If your paycheck depends on color accuracy, you have to use spot-color ink. For example, if UPS hires you to design a flyer for their company party, you want to make sure that your version of brown matches their official brown. Unless you use a spot color (which is consistent because it’s premixed), your brown will be printed using a mix of CMYK inks and may end up looking maroon. • To use specialty inks. If you want to add a bit of pizzazz to your printed image, you can use specialty inks like metallics or a varnish that looks glossy when it’s printed. You can also add a vibrant spot color to a particular area to make that part stand out. However, if you use specialty inks on a CMYK document, you’re adding color separations to your job, which will increase the cost. The most popular brand of spot-color ink is Pantone (www.pantone.com), and be- fore you can use it, you have to create a special channel for it called a spot channel. Each spot color you use needs its very own spot channel. (See Chapter 5 for more on channels.) Note: You’ll also hear Pantone colors called PMS colors, which stands for “Pantone Matching System.” Let’s say you’re preparing the cover photo for the next issue of Cutting Horse maga- zine, and, to reduce printing costs, the magazine has decided to use a grayscale image with one spot color for visual interest. (That way, they’re paying for two separa- tions instead of four.) Your mission is to make the horse’s bridle Pantone Red. No problemo! Just make a selection of the bridle and then create a spot channel for the special ink (see Figure 16-13). Photoshop cs5: The Missing Manual 690
  9. Printing on a Commercial Offset Press Figure 16-13: Top: Once you’ve selected the area you need to color- ize, you can add a new spot channel by choosing New Spot Channel from the Channels panel’s menu (circled, top). Bottom: Click the little color swatch (circled) in the New Spot Channel dialog box to open the “Select spot color” dialog box, and then click the Color Libraries button to see the oh-so-helpful list of Pantone presets shown here. Photoshop will automatically add the ink you choose here to your selection. Here’s how to add a spot channel: 1. Use one of the methods described in Chapter 4 to select the area you want to colorize. If you’re lucky enough to start with the full-color version of the photo, you can easily select the horse’s bridle by using Color Range (page 154). See page 323 for the scoop on converting a color image to black and white and page 329 for changing your image’s color mode to Grayscale. chapter 16: photoshop and print 691
  10. Printing on a Commercial Offset Press 2. From the Channels panel’s menu (see Figure 16-13, top), choose New Spot Channel. Photoshop opens a dialog box where you can name your new channel and pick a color. You can also add a new spot channel by �-clicking (Ctrl-clicking on a PC) the New Channel icon at the bottom of the Channels panel. 3. In the New Spot Channel dialog box, click the color swatch to open the “Select spot color” dialog box and choose an ink color. To see a list of Pantone presets, click the Color Libraries button. In the resulting dialog box, choose a spot color (see Figure 16-13, bottom). From the pop-up menu at the top of the Color Libraries dialog box, choose a color book (if you’re preparing a photo for a magazine, for example, pick “Pantone solid coated” be- cause magazines print on glossy paper). If you know the number of the ink you want (like 032), you can type the number and Photoshop will flip to that color in the list for you, or you can drag the triangles along the vertical scroll bar to find the one you want (you can also use the arrow keys to move through the list of ink swatches). Click the color’s swatch to select it and then click OK to close the Color Libraries dialog box. Note: By picking a color from the Color Library, you don’t have to worry about naming your new spot channel—Photoshop names it automatically. 4. Back in the New Spot Channel dialog box, leave Solidity set to 0% and click OK to close the dialog box. You can think of Solidity as ink opacity, though it affects only the onscreen image and not the printed version. Depending on the image you’re working with, increasing the ink’s opacity so it appears solid and not see-through may be helpful (it’s a personal preference). When you click OK, you’ll see a new spot channel appear in the Channels panel as shown in Figure 16-14. Editing a spot channel Once you’ve created a spot channel, you can change its ink color by double-clicking it in your Channels panel. You can also add or remove color by painting with the Brush tool (or by using any other selection tool and filling it with color, as described on page 181). Since Photoshop shows channel information in grayscale, you can edit a spot channel just like a layer mask (page 113)—by painting with black, white, or shades of gray: • To add color at 100 percent opacity, grab the Brush tool by pressing B and set your foreground color chip to black. Then mouse over to your image and paint where you want to add color. Photoshop cs5: The Missing Manual 692
  11. Printing on a Commercial Offset Press Figure 16-14: Here’s the final cover shot for your magazine. If you peek at the Channels panel, you can see that there are just two channels (and thus two separations). If you send this Photoshop grayscale document straight to InDesign, that program adds a new color swatch for the spot color, and makes sure that the new color prints on top of the black (a technique called overprinting). • To remove color at 100 percent opacity, set your foreground color chip to white before you begin to paint. • To add or remove color at any other opacity, set your foreground color chip to a shade of gray before you paint. Saving a document with spot channels To keep your spot channels intact, you need to save the document in a format that works with spot channels: as a DCS, PSD , or PDF file. So which one do you pick? It depends on what you’re going to do with the file. If you’re the hired Photoshop gun and you’ll be handing the file off to someone else for further fluffing, save it as a PSD file, get your motor runnin’, and head out on the highway (insert guitar riff here). If you’re importing the image into InDesign or QuarkXPress 6.5 or later, you’ll also want to save your image as a PSD file. chapter 16: photoshop and print 693
  12. Printing on a Commercial Offset Press If you’re using the file in QuarkXPress 6 or earlier, you need to save it as a DCS 2.0 or PDF file (see page 695). DCS is a special format that lets you save color separations if your image will be printed on a printing press. To save your document as a DCS file, make sure your document is in either Grayscale or CMYK color mode (page 46) and then choose File➝Save As and pick Photoshop DCS 2.0 from the Format pop-up menu. When you click Save, you’ll see the DCS 2.0 Format dialog box (Figure 16-15) where you can fine-tune the following settings: • Preview. This setting controls which kind of image preview you see in your page-layout software. If your image is headed for a Mac and you want a 256-col- or preview, for example, choose “Macintosh (8 bits/pixel)” or “Macintosh (JPEG)” (the second choice gives you a slightly nicer preview). If it’s headed for a Windows computer, choose “TIFF (8 bits/pixel)”. See the box on page 45 to learn what the term “8 bits” is all about. • DCS. You’ll want to leave this one set at “Single File DCS, No Composite” so Photoshop doesn’t generate all kinds of files that only the printing press peeps know what to do with. • Encoding. This menu lets you control how Photoshop encodes (represents and stores) the print information in your file. If you’re on a Mac, choose Binary. If you’re on a Windows computer, choose ASCII or, for a more compact file, ASCII85. Note: In case you’re wondering, DCS stands for “Desktop Color Separation” and ASCII stands for “American Standard Code for Information Interchange.” ASCII was developed as a way to convert binary (computer) information into text, and ASCII85 is the newest version. This stuff is great bar-bet trivia. Figure 16-15: The DCS 2.0 Format dialog box. DCS 2.0 is one of three formats you can use to save spot channels intact. While most page-layout programs can read DCS files, you may find that using a PDF is easier, as discussed on page 693. Photoshop cs5: The Missing Manual 694
  13. Printing on a Commercial Offset Press Leave the checkboxes at the bottom of the dialog box (Include Halftone Screen, In- clude Transfer Function, Include Vector Data, and Image Interpolation) turned off and then click OK. You’re now ready to import the DCS file into QuarkXPress 6 or earlier. Party on! Saving Spot Colors in PDF Format While DCS 2.0 has long been the standard format for saving documents with spot colors, PDF format is simpler. To see for yourself, follow these steps: 1. Open an image with a spot color and press �-Shift-S (Ctrl+Shift+ S on a PC) or choose File➝Save As. Figure 16-16 shows a file named “Autumn Art_CMYK” that contains the Digi- tal Gypsies logo with an assigned spot color of 810C (the C indicates the coated version of the color). 2. Choose Photoshop PDF from the Format pop-up menu. If your document has layers, turn off the Layers checkbox to flatten the image. 3. Turn on the Spot Colors checkbox. Turning on this checkbox ensures that Photoshop includes your spot colors in your image, along with process colors (CMYK). 4. Rename your image to indicate that it harbors a spot color. For example, rename the image “Autumn Art_CMYK_Spot” and then click Save to summon the Save Adobe PDF dialog box. 5. In the General settings, choose Acrobat 5 (PDF 1.4) from the Compatibility pop-up menu. WoRKARoUNd WoRKSHop Printing Spot-Channel Proofs When Photoshop asks if it’s okay to flatten the layers, click Since spot channels are used only by commercial print- OK. Each spot channel is instantly swallowed up by the ing presses, getting them to print on your own printer for closest matching RGB equivalent. proofing can be…exciting. The solution is to pop into RGB mode temporarily and merge the spot channels. At this point, you can fire it off to your printer without a fuss. The colors won’t be exact, but you’ll get a decent ap- To safeguard your original document, save it and open proximation of what your image will look like when you fin- a copy by choosing Image➝Duplicate. Next, choose ish editing it. After you print it, you can toss the temporary Image➝Mode➝RGB Color and then, in your Channels RGB document and continue editing the original. panel, Shift-click to select each spot channel you’ve cre- ated. Then open the Channels panel’s menu and choose Merge Spot Channel. chapter 16: photoshop and print 695
  14. Printing on a Commercial Offset Press Figure 16-16: Left: You might consider adding the spot color’s name (like Pantone 810C) to your document’s name to help maintain color-naming consistency as you move your image from one program to an- other (for example, from Photoshop to InDesign). Right: If you think you might use these settings again, click the Save Preset button (not shown here; it’s at the bottom left of the dialog box) before you click the Save PDF button. Give your preset a name (like “Print Image PDF”) so you can access it again later from the Adobe PDF Preset pop-up menu at the dialog box’s top left. It’ll come in handy when you learn about duotones later in this chapter. 6. In the Compression settings (click Compression on the left side of the dialog box to see them), choose Do Not Downsample and pick Maximum Quality JPEG or None from the Compression pop-up menu. Picking either compression option should leave you with a high-quality image because Maximum Quality JPEG essentially leaves your images uncompressed. If you aren’t comfortable using a compression format that can reduce your im- age’s quality, choose None instead. 7. In the Output settings, check to make sure the Color Conversion pop-up menu is set to No Conversion. 8. Click Save PDF. You’re now free to send the PDF file to the page-layout program of your choice. If you save the settings you entered as a preset, this method is much faster than sav- ing your file in DCS 2.0 format. However, be sure to ask your printing company if they’ll accept a PDF file with spot colors. Some companies using older equipment may not be familiar with PDFs or may not be able to use them just yet (change is hard, you know!). Photoshop cs5: The Missing Manual 696
  15. Printing on a Commercial Offset Press Printing Duotone (Multitonal) Images One of the advantages of printing with a commercial printer is that you can print duotones and other multitonal images (see the box below) by adding a second ink to your grayscale images. You can add a spot color, another gray ink, or even process colors—great news if you want to colorize a grayscale image, add some tonal depth and richness, or both. Either way, you can create some amazingly beautiful effects as discussed back in Chapter 8. However, it’s really easy to add too much ink, which makes your image way too dark once it’s printed. If that happens, you lose details in the shadows and your contrast goes down the tubes. To produce a truly amazing duotone or multitone image, you need to start with a good quality grayscale image—one that has high contrast and isn’t overly dark. Once you’ve settled on an image, convert it to Grayscale mode (page 46) and then follow these steps: 1. Duplicate your image. Choose Image➝Duplicate and then give the copy a name. To get descriptive with your image name, consider incorporating the word “duotone,” as in “Red Mtn_Duotone”. 2. Choose Image➝Mode➝Duotone. If this option is grayed out, you’re not in Grayscale mode. In that case, choose Grayscale mode first and then switch to Duotone. When the Duotone Options dialog box opens, it reports that your image is a monotone image made from nothing but black ink. Up to Speed Defining Duotones The two keys to creating high-quality duotones are: The term duotone generally refers to a grayscale image that has had additional inks added to it: Technically, if you • Start with a high-quality grayscale image with a good add one ink, it’s a duotone; two inks make it a tritone; and tonal range and high contrast. three inks make it a quadtone, so the correct general term • Substitute your second ink for part of the original is multitonal images. But most folks use the term duotone black ink—rather than just adding it (see page 698). to describe all these alternatives, which can get confusing. This prevents your image from becoming too dark and flat because it’s drowning in ink. So why add other inks to grayscale images to begin with? A couple of reasons: Some folks use duotones to add color to With a bit of practice, you’ll gain confidence in creating an image inexpensively—as you learned on page 684, reduc- duotones and enjoy doing it. However, it’s always a good ing the number of colors in your image can mean a cheaper idea to plan extra time in your production schedule to print print job. However, duotone (or multitone) aficionados will some tests. Since you can’t trust your monitor or proof your tell you the additional inks add tonal range and depth to an own nonprocess duotones (see page 699), a test print is image (and they’re right!). In fact, you can add a second gray worth its weight in gold. ink to enhance tonality without adding any color at all. chapter 16: photoshop and print 697
  16. Printing on a Commercial Offset Press 3. Click the Curve icon to the left of the Black Ink (see Figure 16-17). Clicking this icon opens the Duotone Curve dialog box, where you can peek at how the ink will be applied in your image. For this particular ink, you have a straight 45-degree curve from the highlight to shadow areas, and it’s being ap- plied at 100 percent. Click OK to close the Duotone Curve dialog box. Figure 16-17: Duotone Curves are just like the Curves you learned about back in Chapter 9 (page 406,) except that here they let you know how much ink will be applied to your image’s shadows, midtones, and highlights. The percentages tell you how much ink is being added. 4. Choose Duotone from the Type pop-up menu. This menu gives you a choice of various kinds of multitonal images. If you choose Duotone, Photoshop activates two inks in the dialog box (choosing Tri- tone activate three inks, and so on). However—and this is key—both inks have straight, 45-degree highlight-to-shadow curve lines, which means they print with the same amount of ink in the same color range. That’s not good! If you click on the “Ink 2:” color swatch and load a new color, you’ll add too much ink for the image to print decently. So instead of editing the Duotone Curves your- self, use one of the many presets as described in the next step. 5. Click the Preset pop-up menu and choose one of the Duotone presets from the list (see Figure 16-18, top). Feel free to experiment with the wide variety of choices in the Preset menu. Some of the selections, like the true duotones, offer anywhere from one to four options, which represent substitutions for the second ink ranging from stronger to weaker. These are excellent starting points for your creations. There’s nothing wrong with tweaking the Duotone Curves to fine-tune your results, but you’ll want to print some tests first to make sure you’re not adding too much ink. Photoshop cs5: The Missing Manual 698
  17. Printing on a Commercial Offset Press Testing duotones is tough because you can’t proof them unless you’ve made a duotone out of process colors (which really makes it a quadtone). If you select a preset with inks not available on your printer, you won’t get an accurate proof. The best you can do is contact your printing company and see if they’ll print you a test on the paper they’ll use for the final image. If you don’t need the proof right away, they may be able to hold onto it and slide it in with another job that uses a similar ink-and-paper combo. Figure 16-18: Top: Once you pick a pre- set, peek at the curves for each new ink. Notice the curve for the black ink is reduced to make room for the other inks, which have straight, full-ink curves. Bottom: If you choose Quadtone from the Type menu and “CMYK wm” from the Preset menu (wm stands for “warm”), you can add a nice warm tone to your image (as shown on page 700). If you’re working with a CMYK image, this is a fine choice; however, if you’re working with a grayscale document and you don’t want to add many differ- ent inks, go for one of the Duotone options, which will add one ink instead of three. 6. Save your document as an EPS or PDF file. Here’s yet another opportunity to chat with your printing company! Give 'em a ring and ask if they prefer EPS or PDF format for duotones or multitones. If they say EPS, ask them which settings they prefer, choose File➝Save As, and then pick Photoshop EPS from the Format pop-up menu. In the EPS Options dialog box (Figure 16-19, bottom), choose an 8-bit option from the Preview pop-up menu and pick Binary from the Encoding pop-up menu. Unless your printing company tells you otherwise, leave the rest of the options turned off and click OK. chapter 16: photoshop and print 699
  18. Printing on a Commercial Offset Press To save your duotone as a PDF file instead, you can use the same settings you used to save a spot-color image in the previous section (page 695). Figure 16-19: As you can see, the difference between a grayscale image (top) and a quadtone (bottom) can be impressive. Proofing Images Onscreen When it comes to sending images out for printing, it’d be nice to peek into the fu- ture and see what they’ll look like. Happily, Photoshop can create an onscreen proof simulation known as a soft-proof, a straightforward process using the same color profiles you learned about in the previous sections. Here’s how to do it: Photoshop cs5: The Missing Manual 700
  19. Printing on a Commercial Offset Press 1. Calibrate your monitor using the tools described earlier (page 667). If you haven’t calibrated your monitor, soft-proofing is a galactic waste of time. 2. Open an RGB image you intend to print. You can soft-proof either RGB or CMYK images, but it’s especially cool to proof an RGB image and see what it will print like in CMYK without having to color- convert it first. 3. Choose Window➝Arrange➝“New Window for” to create a second window showing a copy of your image. Position the windows so they’re side by side by choosing the 2-Up display from the Application bar’s Arrange Documents menu. 4. Click the right-hand window to activate it and then choose View➝Proof Setup➝Custom. 5. In the resulting Customize Proof Condition dialog box, turn on the Preview checkbox (Figure 16-20, top). 6. From the “Device to Simulate” menu, choose the profile for your final printer. If your image is headed to a printing press, for example, pick your old profile friend, “U.S. Sheetfed v2”. 7. Choose Perceptual from the Rendering Intent menu and turn on the Black Point Compensation checkbox. Perceptual takes into account how humans see color. The Black Point Compen- sation option makes sure that Photoshop maps your black values and converts them to blacks in your final print, which helps preserve the contrast of your original. 8. In the “Display Options (On-Screen)” area, turn on the Simulate Paper Color checkbox. Watch your onscreen proof change as you turn this option on and off. 9. Sit back and examine the differences between your left and right windows. You can apply soft-proofing to other printers like your inkjet printer or a digital press (see page 705). All you need to achieve good results is a calibrated monitor, an accurate printer, and a paper-specific profile. That said, soft-proofing isn’t 100 per- cent accurate, but it’s better than nothing and you’ll almost always find it useful. It’s also a good tool to help control your client’s expectations, especially when the client is printing on cheap, low-quality paper. chapter 16: photoshop and print 701
  20. Printing on a Commercial Offset Press Figure 16-20: Top: Turning on Preview lets you see the results of your proof settings without clicking the OK button. Bottom: Notice that the image on the right is slightly less saturated and has lower overall contrast than the original image on the left (which looks kind of flat). You can also select other profiles and see how they affect the soft-proofing results. Printing Color Separations To avoid running into unexpected printing costs, it’s a good idea to print your separations (called seps around the water cooler) to make sure another color hasn’t sneaked its way into your document—especially if you’ve toyed with some spot col- ors that you’re not going to use. Honestly, though, you probably won’t use Photoshop to print separations at all—in most cases, you’ll place an RGB or CMYK image in a page-layout program (like InDesign), along with text and other images, and let it print the separations. The page-layout program does the final printing using its print dialog box. However, just in case you ever do need to print separations from Photoshop, you can visit this book’s Missing CD page at www.missingmanuals.com/ cds for step-by-step instructions. Photoshop cs5: The Missing Manual 702
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