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Defining a Spot Color

Before you define a spot color, it would be good if we knocked out the area on the four printing plates where the burst will go. If you don't, you'll get a puddle on the sign instead of the exciting hot-pink color. This takes only one step, though, and it's only a single step on the way to defining the spot color channel.

Obviously, the pressman will have five plates to work with: the CMYK plates and the spot color plate. The spot color plate needs some refining, and the silhouette of the burst will be deleted from the file after it has served its purpose. In the following steps, you will define the color that is going to be used on the spot color plate. And Photoshop actually lets you see what the spot color area looks like, without requiring you to print the work.

Here's how to create a knockout and then change the Alpha 2 channel into a spot color channel:

  1. Ctrl(@Cmd)+click on the Alpha 1 channel title on the Channels palette, while keeping the RGB composite view of the image as the current editing view.

  2. Make sure that white is your current background color. See the tiny icon on the lower left of the color selection boxes on the toolbox? Click it to restore the color selection boxes to their default of black as foreground (the color you paint with) and white as the background color (the color you erase to). Press Delete (Backspace)—and voila!—as you can see in Figure 6, all three color channels plus the color composite channel now have a white burst knocked through them. Press Ctrl(@Cmd)+D to deselect the marquee selection. The white knockout will support the words "NEW!" and you'll shortly add a spot color surrounding for the white lettering.

    Figure 6 You need to knock out the burst area on all the color channels so that the word "NEW!" has a chance to be white!

  3. Choose Mode and then choose CMYK for the image. You will not notice a lot of color change because the image mostly falls inside of the color space that CMYK color engenders.

  4. Press Ctrl(@Cmd)+K, check the Short PANTONE Names in General Preferences, and then click OK. We're going to try something special down the road, and not all applications can read the full name of color-specification systems.

  5. Double-click on the Alpha 2 channel title. Notice something different? Spot Color is now a selection button. Click it, as shown in Figure 7, and then click the Color swatch because your client does not want RGB mode red as the burst's color.

    Figure 7 Create a Spot color channel from the Alpha 2 channel, and then click on the color swatch to walk into a whole new world of color.

  6. In the Color Picker, choose Custom. Then choose the type of paper and the specifications for color that Mr. Cosmic should have given to you before you began. For simplicity's purpose, let's assume that the color specification is PANTONE, and your art is going to coated stock (most shopping cart ads are on glossy stock). Choose PANTONE Coated (callout #2 in Figure 8) from the drop-down box, and then settle on a nice hot color such as PANTONE 2375CVC (callout #3 in Figure 8).


    Let the Custom Color Picker Do Your Work-If a client specifies a color from a color-specification system, obey them. It's really easy to find the color they want: You start typing the number of the color, and the Custom Color Picker will go right to that color.

    Figure 8 Choose a spot color from whatever color specification system your client wants, and pick the color by number value even if you personally think it's hideous.

  7. Click OK to return to the Channel Options box, and then double-click on the newly named channel title. Surprise of surprises—you're greeted with the Spot Channel Options dialog box. As you can see in Figure 9, Photoshop has entered the short name of the PANTONE color, and all you have to do is increase the solidity of the ink to 100% and then click OK.

Figure 9 The Spot Channel Options dialog box contains the proper name for the ink, as well as what percentage of the ink (the solidity) you want applied.


The Skinny on Shiny Areas of Book Covers-If you've purchased more than one Bouton book in your life (or any New Riders book, for that matter), you've probably noticed some fancy outlining on the cover and that some areas are dull while others look glossy. How was this done? It's simple—the designer masked over the areas that should be glossy, saved the information to an Alpha channel, and converted it to a spot channel. The color makes no difference, but the Solidity is 0%. That's how you selectively apply varnish to a book cover.

About this Article

This article is excerpted from Inside Adobe Photoshop 6 Limited Edition, by Gary David Bouton, Barbara Bouton, Gary Kubicek, Mara Zebest Nathanson (New Riders Publishing, 2001, 0-7357-1159-3).
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