Photoshop CS3 for Screen Printers- P9

Photoshop CS3 for Screen Printers- P9: The toolbox is the heart of Photoshop CS3, and where you’ll find thetools you need to create your artwork and perform editing tasks. Fromthe toolbox you can access the selection tools, shape tools, type tools,Crop tool, and eraser tools. These are basic tools that any screen printeror graphic artist needs.
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Photoshop CS3 for Screen Printers- P9216 Part II / Creating Artwork and Logos n Indexed Color: This mode uses 1 to 256 colors. You can convert an RGB image to an indexed color image, and Photoshop will look at the colors and convert them to the colors available in the indexed color model. Indexed color can be used for web images but is used in screen printing as well. Screen printers can use indexing to color separate an image using only a few colors, and those colors can be hand picked.. Note: You can switch between color modes using the Image>Mode menu choices.Introduction to Spot Color Spot color images are those images that can be printed using a limited number of colors and also have a limited number of colors in the design. Generally, spot color prints are the easiest kind of images to both screen print and color separate. Most of the logos that you’ve seen in this book up to this point have been spot color designs. Spot color prints are not photorealistic like process color prints; spot color images are created using text, clip art, and color. Figure 11-4 shows a true spot color design. In Figure 11-4, the puzzle pieces are different colors and the writing is black. Each puzzle piece has a black outline, so in this spot color design, the colors touch. If you’re new to screen printing, you’ll probably be more comfortable with designs whose colors don’t touch (since the calibration of the press isn’t such a big deal), so you might want to remove this part of the design after you print out the color separations (or before). As you progress, you’ll become more comfortable with designs where colors touch and even fade into one another. True spot color images (those whose colors do not fade into each other or contain highlights or shadows) can be printed using premixed inks. Each spot color requires that a screen be created specifically for that color and a plate on the press for printing it. Chapter 11 / Working with Colors—An Introduction 217 You’ll create lots of true spot color designs as you build your busi- ness (and certainly lots of them after). In our shop, 60 percent of our work is this type of spot color prints for baseball teams, school teams or clubs, churches, family reunions, and more. Many of our clients only want a single color on a shirt, which is the least expensive way to go, and this type of design only requires one screen. Figure 11-4: Spot color design. Note: While “true” spot color designs can be printed without halftones, spot color images that have highlights or whose colors fade into one another will require halftone screens and a different process. There will be much more information on the different types of spot color processes in Chapter 22.218 Part II / Creating Artwork and LogosIntroduction to Indexed Color Indexed color is used often to create graphics for the Internet. There, the fewer colors an image has, the faster it can be downloaded to a viewer’s computer. Fast is the key in Internet talk. Indexed color is popular among screen printers too, since fewer colors can mean less work for the screen printer. Of course, you can’t create millions of colors like you can with RGB or CMYK, so it isn’t always the best solution. However, for designs that have a limited number of colors, indexed color can work quite well. Figure 11-5 shows an image that could be indexed. Figure 11-5: Indexed color image Indexed color images can contain up to 256 colors and are created (con- verted to indexed color) from RGB images. You can choose how many of these 256 to use, and you can pick as few as two. I usually choose four and make adjustments after seeing the result. (We discuss how to do this in Chapter 24.) During the conversion, Photoshop looks at all of the Chapter 11 / Working with Colors—An Introduction 219 colors in the RGB design and figures out how to create those colors using only the colors you specified or the available 256 colors. This obvi- ously creates some deterioration in the image, but if the image only has a few colors to begin with, you probably won’t notice.] Tip: When working with an image that only has a few colors (say, fewer than 50 or so), you can try indexing. If you have a four-station press, choose the four main colors you feel are in the image when performing the color separation. You’ll be surprised what you can create from just four colors!Introduction to Process Color Process color is used when you want to print photorealistic prints. Pro- cess color printing requires that you create unique halftone screens, one for each of the CMYK channels, and additional screens as needed for an underbase, spot colors, or highlights. (We discuss how to do this in Chap- ter 23.) Halftones are really just dots that control how much ink should be put in a particular part of the image. For instance, if one screen has small dots for the black ink and another screen has large dots for the yel- low ink, the resulting color will be a medium to light yellow when the inks are both placed on the substrate. You can see the percentages of CMYK in a color using the Info palette. Figure 11-6 shows a print that would require process color. The zebra picture came from the Photoshop 6.0 program files, and I added some text and a border. You can get similar sample images from the Photoshop CS3 Sample folder.220 Part II / Creating Artwork and Logos ...