7. The Digital Darkroom: Layers, Masks, Selections, Channels, and More

What would you say if we told you that you could perform color correction, use dodging and burning, build up density in overexposed areas, open up underexposed areas, and more—all with a minimum of image degradation and with an unlimited number of undos? You’d probably just laugh at us. But in this chapter we’ll show you how.

You can do a lot using the controls we’ve already covered, but you can go much further, with more freedom to experiment, when you apply them as adjustment layers rather than simply burning the changes into your image. The controls in adjustment layers behave just as they do on a flat file, but with far more freedom and flexibility. You can change your adjustment settings at any time, and vary their strength globally by changing the adjustment layer’s opacity. Even better, you can turn global corrections into local ones by painting on the adjustment layer’s layer mask. In effect, you have not just unlimited undo, but selective, partial undo.