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Home , Channel (digital image), Color image, Spot color

systems from TrueMatch, Focoltone, Toyo, and other d. Click the swatch you desire to select it, and click OK. matching systems. Here is how it works: Once you pick a predefined color, do not rename or edit it, if you 1. Decide what kind of paper stock you will use, because paper plan to print it as a . makes a huge difference in color. For example, makes swatch books for three main kinds of paper stock: C for Coated paper, U for Uncoated paper and M for Matte paper. Guided Exercise 1: Create a Spot

2. Select the swatch or swatches you need from the Color appropriate swatch book—not the color you see on your One common purpose for creating a monitor or print on your desktop printer, since those spot color channel is to use one or may not be accurate. more graphics in a poster, flyer, or 3. Use the Photoshop to locate your job color(s) longer document that will be printed from one of the color matching systems: in plus one additional color. In a. Click the Color this activity, you will begin with a of a gerber daisy Libraries posted on the StockXchng by Lonnie Spath; Queensbury; NY. button. (It You will end up with a version of the image, along with was called the a spot color channel to colorize the flower. Custom button in 1. Open the file namedgerber.psd in the student_folder. previous versions 2. Choose Select > Load Selection. We made an alpha of Photoshop.) channel of the flower to save you time. b. Choose the custom color system from the Book popup menu shown to the right.

c. Either type in the swatch book number 3. Click the Invert box, make sure the channel is flower, and (if you know click OK to select everything but the flower. it) or use the 4. Use any of the techniques from chapter 3 to desaturate the color spectrum background part of the image. The goal is to keep as much to locate colors in the range you seek.

Chapter 4: Spot and Process Colors Page 53 contrast and detail as possible. We used a Channel Mixer 9. If you want, test the spot channel. With your foreground adjustment layer with these settings: color set to black, and the Brush tool chosen, paint on the spot channel and notice that it colorizes the image. Undo 5. If you used an adjustment layer to desaturate, merge down when you are done. once you are pleased with the results. You should merge adjustment layers before converting an image from RGB to 10. Activate the RGB composite (this step is critical), and then grayscale in order to preserve image tonality. choose Image > Mode > Grayscale to convert the image to grayscale. Click OK when 6. With the Eyedropper tool set to Sample Size of 5 x 5 Photoshop asks permission to Average, sample a bright, vivid part of the flower to make discard color information—it will it the foreground not delete the spot channel or the color. alpha channel. Now when Photoshop looks for a spot color, it will begin with 11. Load the flower selection, and with the Gray channel active, the one closest to the foreground color. choose Edit > Cut. There is now a big area where the 7. Select the flower, and chooseNew Spot Channel from the flower once was. Channels menu. 12. Load the flower selection again, 8. Change the Solidity and with the spot channel active, value from the default choose Edit > Paste. 0% to 30%. The spot colored flower looks Solidity is only for screen display, and has no relationship very different from the full color with how the color will actually print on the press. Real version, since it is only printed World Photoshop CS recommends 30% (p. 511) because: with one color of ink, and not the millions of colors in the “If we used 100%, we might forget that other colors might RGB image. show through the spot color, causing mottling....If the spot 13. Save the document as gerber-spot.psd in the location of color is a varnish, we’d set the Solidity to zero, because your choice. varnishes are almost transparent.” Notice that the spot channel Guided Exercise 2: Saving a Spot thumbnail is completely white. White represents the absence of Channel File in PDF Format the color, black the presence of the Your document is now done, and ready to bring to the printer., color, and are tints import into a page layout program, or send to a newspaper or of the color. magazine for publicaiton. More and more, Protable Document

Chapter 4: Spot and Process Colors Page 54 Format, or PDF is used because it is a standardized format. But the Format list. the problem has been that PDF permits so many different saving 3. Be sure Spot Colors option is checked, and then click Save. options, that the format has not been standard enough. 4. Click OK when you see this warning: Photoshop CS2 has expanded its PDF save options to support three PDF subsets that are more predictable in the publishing world. According to Photoshop Help:

PDF/X‑1a (2001 and 2003) PDF/X‑1a is an ISO standard for graphic content exchange. PDF/X‑1a requires all fonts to be embedded, the appropriate PDF bounding boxes to be specified, and color to appear as CMYK, spot colors, or both. PDF/X-compliant files must contain information describing the condition for which they are prepared. PDF files 5. Choose Press Quality for the Adobe PDF Preset and then created with PDF/X‑1a compliance can be opened in Acrobat choose PDF/X-1a:2001 for the Standard. When you 4.0 and Acrobat Reader 4.0 and later. choose the standard, the preset will show that is has been PDF/X-2 is not widely used. modified. PDF/X‑3 (2002 and 2003) Like PDF/X‑1a, PDF/X‑3 is an ISO standard for graphic content exchange. The main difference is that PDF/X‑3 allows the use of and device-independent color (CIE Lab, ICC- based color spaces, CalRGB, and CalGray) in addition to CMYK and spot colors. You can use ICC color profiles to specify color data later in the workflow, at the output device. 6. Click Save PDF to save the gerber file inPDF/X-1a:2001 PDF files created with PDF/X‑3 compliance can be opened in format. Acrobat 4.0 and Acrobat Reader 4.0 and later. 7. If you want, open gerber-spot.pdf in Adobe Reader or You can read more about the specifics of these formats at: Acrobat to look at it. Notice that the spot channel shows first, http://www.pdf-x.com/pdfx_123_1.php and find more detailed and then vanishes to reveal the gray channel with a white information from PlanetPDF: hole where the spot channel http://www.planetpdf.com/mainpage.asp?webpageid=1220. will appear. If you change the view, you will again glimpse the Let’s look at the specifics: underlying flower before it is 1. Open gerber-spot.psd if it is not already open. covered by the gray channel. 2. Choose File > Save As, and choose Photoshop PDF from

Chapter 4: Spot and Process Colors Page 55