Photoshop® CS4 Bible

8.7. Summary

This chapter described different kinds of layers, how to use them, and how to apply various layer effects. Following are key concepts:

You can put objects in your Photoshop document on separate layers and work on the objects separately. This makes your document much more flexible and easy to change.

Layer masks are used to totally or partially hide objects on a layer, and with layer masks, you can easily show any part of the object again at any time. This is an advantage over erasing parts of an image because it is easy to undo.

Adjustment layers are layers that don't contain pixels but can be used to alter how pixels on underlying layers appear. They can increase saturation, lighten or darken, increase or decrease contrast, make changes to colors, and more. Flexibility is a big part of adjustment layers in that you can edit or delete them at any time. Layer styles can be used to add one or more effects to layer content, such as a drop shadow, bevel, or glow.

A blending mode can be applied to a layer to affect how the pixels on the layer interact, or blend, with pixels on underlying layers. Blending modes can be used to lighten, darken, affect contrast or color, and more. Commonly used blending modes include Multiply, Screen, Lighten, Darken, Color, and Luminosity.

Smart Objects are layers that store one or more layers' content or store an Illustrator file's content in such a way that it remembers the content's original characteristics, even if you transform or apply ...