Absolute Beginner's Guide to Digital Photography

With Photoshop, you have the capability to view and

edit channels; however, in Photoshop Elements, you

can save only selections; iPhoto does not allow you

to save channels or selections. Because color chan-

nels are more advanced and more complex than

layers, it’s important to know the difference

between a layer and a color channel:

■ A layer is an individual, full-color image.

Layers can be stacked to create a composite

image.

■ Color channels are the color components of

a layer. Each RGB layer has three color

channels.

■ When you edit color channels, you edit the

color channels of one layer at a time. The

active layer (the one selected in the Layers palette) is the only layer on which

the color channel editing is happening.

Sometimes it can help to edit only one color channel. On occasion, one channel

may be less sharp than the others, or it may appear too grainy (see Figure 17.1). To

fix this, you might remove grain in one color channel by blurring it with a filter,

while you sharpen another color channel with a different filter. If you’d like to try

this yourself and have a copy of Photoshop, just follow these steps:

256 ABSOLUTE BEGINNER’S GUIDE TODIGITAL PHOTOGRAPHY

Photoshop Elements

does not include channels

or the Channels palette. Any ver-

sion of Photoshop more recent

than Photoshop 3 includes chan-

nels, however.

FIGURE 17.1

Removing grain

using the

Despeckle filter

in one color

channel.