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Spot-Color Separations
Photoshop permits you to add spot colors to your images. Although it’s unlikely that you’ll use spot colors to widen the gamut of your photographs — after all, scanners can’t scan spot colors and Photoshop can’t automatically lift them out of, say, the RGB color space — you may want to toss in a spot color to highlight a logo, a line of type, or some other special element.For example, suppose you have a full-color image of a jet ski. The logo along the side of the boat is fully visible, just as the client wants it, but the color is off. Normally, the logo appears in Pantone 265 purple. But the CMYK equivalent for this color looks about three shades darker, four shades redder, and several times muddier. The only solution is to assign the proper spot color — Pantone 265 — to the logo. The following steps tell how.STEPS: Adding a Spot Color to an Image
Select the logo. You can use the magic wand tool or a more exacting method, as described in Chapters 8 and 9.
Fill the selection with white. Press D to get the default foreground and background colors and then press Ctrl+Backspace (z -Delete on the Mac). It’s important that you erase the old logo so that it appears in pure spot color without any mixing with the CMYK inks. But do not deselect your selection! It must remain active for Step 5 to work.
Create a new spot channel. As explained in Chapter 4, the easiest way to do this is to Ctrl-click (Win) or z -click (Mac) the page icon at the bottom of the Channels palette. But you can also choose New Spot Channel from the Channels palette menu if you prefer.
Set the color to Pantone 265. Click the Color swatch in the New Spot Channel dialog box. Then select Pantone 265 from the Custom Colors dialog box. (If the Color Picker appears instead, click the Custom button.)
Press Enter or Return or click OK twice. Photoshop adds the new spot color to the Channels palette and fills the selection. Your logo automatically appears in the spot color. (Cool, huh?)
Choose Image Trap. It’s a good idea to trap the spot color so that it covers up any gaps that may result from misregistration. Enter a value of 1 or 2 pixels and press Enter or Return. Photoshop spreads the logo but leaves the CMYK image alone. Very intelligent program, that Photoshop.
Save the image. You have two choices of formats, native Photoshop or DCS2.0. If you want to import the image to a different program, use the latter.
Naturally, you don’t want to trust Photoshop’s on-screen representation of the spot color any more than you would in Illustrator, QuarkXPress, or any other program. The screen version is an approximation, nothing more. Therefore, it’s a good idea to have a Pantone swatch book on hand so that you know exactly what the color should look like when printed. (If the printed logo doesn’t match the swatch book, it’s the printer’s fault, not Photoshop’s.)
