Gradient maps let you use gradients in nonlinear ways. So instead of a rainbow that shades from one direction to another, with a gradient map, Elements substitutes the gradient’s colors for the image’s existing colors. You can use gradient maps for funky special effects as well as serious photo corrections.

When you create a gradient map, Elements plots out the brightness values in your image and applies those values to a gradient (light to dark). Then Elements replaces the existing colors with the gradient you choose, using the lightness values as a guide to determine which color goes where. That sounds complicated, and it is; but if you try it, you’ll quickly see what’s going on. Take a look at Figure 13-24, where applying a gradient map dramatically livens up a dull photo. But that’s not all gradient maps are good for. They can also be valuable tools for straight retouching. See the box on Using Gradients for Color Correction to learn how to use gradients to fix the color in photos.