Photoshop CS2 All-in-One Desk Reference For Dummies- P17

Photoshop CS2 All-in-One Desk Reference For Dummies- P17:Barbara Obermeier is principal of Obermeier Design, a graphic design studioin 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, technicaleditor, or layout designer for numerous books. Barb also teaches computergraphics at Brooks Institute; the University of California, Santa Barbara; andVentura College....
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Photoshop CS2 All-in-One Desk Reference For Dummies- P17458 Book VI: Channels and MasksChapter 2: Quick andDirty MaskingIn This Chapter Using Quick Masks Working with Color Range Selecting by erasing Extracting an imageM asking is essentially just another way of making a selection. Instead of defining your selection with a selection outline, masks define yourselection with 256 levels of gray, which allows you to have varying levels ofselection. Photoshop masks or protects unselected pixels from any com-mands you execute. Photoshop doesn’t mask selected pixels,making them fair game to any executed commands.Different types of masks have different purposes —channel masks, layer masks, and vector masks. Youcan use them to temporarily make a selection, saveand load selections, define vector shapes, selec-tively apply an adjustment layer or filter, blend onelayer into another, and so on. Although selectingwith the Marquee, Lasso, Magic Wand, and Pentools can be fine, you’ll soon find that these toolshave a limited repertoire: You can’t use them withmuch accuracy on more complex images. That’swhen you turn to masking.Most things that pack a powerful punch are either expen-sive or hard to master, or both. Well, you already forked out apretty penny for Photoshop. And yes, masking isn’t for those whoget their selections via a drive-thru window. To help you with the learningcurve, in this chapter, I ease you into masking by using Photoshop’s auto-mated masking tools. Although they aren’t quite as accurate as the hard-core masking I cover in Book VI, Chapter 3, they are easier on you, and withcertain images (or a serious time crunch), the quick-and-dirty masking toolsget the job done.460 Working with Quick MasksWorking with Quick Masks As you can probably guess from the name, Quick Masks allow you to create and edit selections quickly without having to bother with the Channels palette. Although you don’t really create an end-product mask per se, the way you go about getting your selection is “mask-like.” They are also user friendly in that they allow you to see your image while you’re working. You can begin your Quick Mask by using a selection tool or a painting tool. After you have your Quick Mask, you can edit the mask using any painting or editing tool. Quick Masks are temporary, so if you create one you really like, be sure and choose Select➪Save Selection at the end of the following steps. (Note that you have to be out of Quick Mask mode to do this.) That way you can save the selection as an alpha channel. For more on saving selections as alpha channels, see Book VI, Chapter 1. Follow these steps to create your very own Quick Mask: 1. Open a new document and, using any selection tool, select the ele- ment you want in your image. Don’t worry about getting the selection perfect. You can fine-tune your selection after you have the Quick Mask in place. Note that you can also just paint your mask from scratch. But I think that starting with a selection is easier. 2. Click the Quick Mask Mode button in the Tools palette. A color overlay covers and pro- tects the area outside the selec- tion, as shown in Figure 2-1. The selected pixels are unprotected. 3. Refine the mask by selecting a painting or editing tool. Corbis Digital Stock Paint with black to add to the Figure 2-1: When using a Quick Mask, a mask, thereby making the selection color overlay represents the unselected, or smaller. Even though you are paint- protected, areas. ing with black, your strokes will show up as a red overlay. This red overlay is a visual carryover from back in the day when artists used rubylith (red transparent material) to mask portions of their art during airbrushing. Paint with white to delete Working with Quick Masks 461 from the mask, making the selection larger. Paint with a shade of gray to par- tially select the pixels. Partially selected pixels take on a semitransparent look, perfect for feathered edges, as you can see in Figure 2-2. 4. After you finish editing your mask, shown in Figure 2-3, click the Standard Mode button in the Tools palette to exit the Quick Mask. Corbis Digital Stock The overlay disappears and a selection Figure 2-2: Clean up your Quick ...