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Photoshop CS2 All-in-One Desk Reference For Dummies- P18

Photoshop CS2 All-in-One Desk Reference For Dummies- P18:Barbara Obermeier is principal of Obermeier Design, a graphic design studio in Ventura, California. She’s the author of Photoshop Album For Dummies, coauthor of Adobe Master Class: Illustrator Illuminated, Photoshop 7 For Dummies, and Illustrator 10 For Dummies. She has contributed as coauthor, technical editor, or layout designer for numerous books. Barb also teaches computer graphics at Brooks Institute; the University of California, Santa Barbara; and Ventura College | 488 Masking Hair Fur and Other Wispy Things continued It is best to start with the channel that contains the most contrast between what you want to select and what you don t. If it s a toss-up go with the channel that makes selecting the difficult part of the image easiest in my example that s the hair . In my example I m using the Blue channel. 3. Choose Duplicate Channel from the Channels palette pop-up menu. Name the channel mask and click OK. You ve created an alpha channel for the mask shown in the figure. Now you can edit the mask without harming the original channel. 4. Choose ImageOAdjustmentsO Levels and boost the contrast in the image by adjusting the Input sliders for shadows midtones and highlights. If you need help using the Levels adjustment see Book VIII Chapter 1. 5. Select the person and his or her hair. You can do that one of two ways By selecting the person. By selecting the background first and then inverting the selection. In a mask traditionally white represents a selected area black represents an unselected area and gray represents a partially selected area. 6. Adjust the Levels settings by dragging your shadows midtones and highlights sliders so that the element you want to select is either all white or all black with a little gray in the wispy areas. In other words you want to change most of the pixels in the image to either black or white. In my example because my guy is darker than the background I adjusted the contrast to make the subject as black as I could while making the background lighter. You can see the result in the figure. Masking Hair Fur and Other Wispy Things 489 Book VI Chapter 3 7. If you think the edges of your image need to be accentuated you can apply a High Pass filter FilterOOtherOHigh Pass before you apply the Level adjustment. Getting Exact with Advanced Masking Techniques High Pass turns your overall image gray while leaving the edges white. Don t use too low a radius value start with a setting between 8 and 10 or .