Adobe 23101335 User Guide - Page 207

ADOBE PHOTOSHOP 6.0 197 User Guide About masks (Photoshop) Masks let you isolate and protect areas of an image as you apply color changes, filters, or other effects to the rest of the image. When you select part of an image, the area that is not selected is "masked" or protected from editing. You can also use masks for complex image editing such as gradually applying color or filter effects to an image. In addition, masks let you save and reuse timeconsuming selections as alpha channels. (Alpha channels can be converted to selections and then used for image editing.) Because masks are stored as 8-bit grayscale channels, you can refine and edit them using the full array of painting and editing tools. When a mask channel is selected in the Channels palette, foreground and background colors appear as grayscale values. (See "Creating temporary masks in Quick Mask mode (Photoshop)" on page 197.) A B C A. Opaque mask used to protect the background and color the shell. B. Opaque mask used to protect the shell and color the background. C. Semitransparent mask used to color the background and part of the shell. In Photoshop, you can create masks, all stored at least temporarily as grayscale channels, in the following ways: • Quick Mask mode lets you create and view a temporary mask for an image. Temporary masks are useful when you don't want to save the mask for later use. (See "Creating temporary masks in Quick Mask mode (Photoshop)" on page 197.) • Alpha channels let you save and load a selection to be used as a mask. (See "Storing masks in alpha channels" on page 199.) • Layer masks and layer clipping paths let you produce a mix of soft and hard masking edges on the same layer. By making changes to the layer mask or the layer clipping path, you can apply a variety of special effects. (See "Hiding portions of a layer" on page 237.) Creating temporary masks in Quick Mask mode (Photoshop) Quick Mask mode lets you edit any selection as a mask without using the Channels palette and while viewing your image. The advantage of editing your selection as a mask is that you can use almost any Photoshop tool or filter to modify the mask. For example, if you create a rectangular selection with the marquee tool, you can enter Quick Mask mode and use the paintbrush to extend or contract the selection, or you can use a filter to distort the edges of the selection. You can also use selection tools, because the quick mask is not a selection.