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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 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 | 458 Book VI Channels and Masks Chapter 2 Quick and Dirty Masking In This Chapter Using Quick Masks Working with Color Range Selecting by erasing Extracting an image JtyKasking is essentially just another way of making a selection. Instead of defining your selection with a selection outline masks define your selection with 256 levels of gray which allows you to have varying levels of selection. 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. You can use them to temporarily make a selection save and load selections define vector shapes selectively apply an adjustment layer or filter blend one layer into another and so on. Although selecting with the Marquee Lasso Magic Wand and Pen tools can be fine you ll soon find that these tools have a limited repertoire You can t use them with much accuracy on more complex images. That s when you turn to masking. Most things that pack a powerful punch are either e sive or hard to master or both. Well you already forked out a pretty penny for Photoshop. And yes masking isn t for those who get their selections via a drive-thru window. To help you with the learning curve in this chapter I ease you into masking by using Photoshop s automated masking tools. Although they aren t quite as accurate as the hardcore masking I cover in Book VI Chapter 3 they are easier on you and with certain images or a serious time crunch the quick-and-dirty masking tools get the job done. 460 Working with Quick Masks Working 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