Adjustment layers

There are two ways to apply adjustment commands: They can be applied directly to the current layer (or to a selection on the current layer), or they can be applied via an adjustment layer. We prefer the latter method because it offers the most flexibility.

Unlike a normal layer, an adjustment layer affects all the visible layers below it—not just the current layer. But the beauty of an adjustment layer is that it doesn’t actually change pixels until it’s merged with the layer below it (Ctrl-E/Cmd-E), so you can use it to try out various effects. We think of adjustment layers as a handy way to preview color and tonal adjustments.