Photoshop® CS3 Channels and Masks Bible

Chapter 17. Masking Ambiguous Edges

IN THIS CHAPTER

• Making selections with color

• Working with color range

• Selecting fine detail with adjustment layers and color range

• Extracting images

Preserving edge detail when compositing an image is of critical importance. Poorly made selections can compromise the credibility of your image. You may encounter images that are tough to select because they have ambiguous surroundings or complex content. Perhaps fine hair or fur need to be selected, or the leaves on a tree. What do you do with these problem images? Photoshop offers a number of techniques that perform these miracle selections. The techniques vary from using the core channelinformation to make a selection, to implementing industrial-strength selection commands, to performing full-blown extractions with a special filter.

The purpose of creating a quality mask is to preserve as much edge detail as possible while preserving the subtle transitional tones. Ultimately, a mask is a silhouette whose edge precisely follows the contour of the area that it selects. When the edges of an image are ambiguous the mask needs to express this ambiguity in the form of variable levels of transparency.

The tools and techniques that create these types of masks are presented in this chapter. They don't necessarily make selecting ambiguous edges easy but they get the job done with precision.

Making Selections with Color Channels

You can use an image's core color information found in the Channels palette to make selections ...