The first rule to tinkering is to save all the parts.
The Layers palette is like the mother everybody wanted as a teenager. Instead of yelling at you to clean your room, she patiently keeps track of all your stuff and she doesn't care if you are neat and tidy, or an all-out slob. She is command central for everything you will ever do in Photoshop and the better you get to know her, the more you will be rewarded for your efforts. Whether you have just a few elements in your document, or hundreds, the Layers palette keeps everything organized, and gives you an amazing number of options for how to make the elements relate to each other. There's no getting around this one; learning all the nooks and crannies and knowing how to use this palette effectively is absolutely essential to your success in Photoshop. The good news is that Layers—as opposed to some of Photoshop's more complex features—is relatively easy territory to conquer. So the next time you have an urge to shout "Ma! Where are my blue socks?!", take a look in the Layers palette, because you never know what you might find in there.
How Do Layers Work?
At first glance, layers might seem complex, but the idea behind them is rather simple. You isolate different parts of your image onto independent layers ( Figure 3.1 ). These layers act as if they are separate documents stacked one on top of the other. By putting each image on its own layer, you can freely change your document's look and layout without committing to the changes. If you paint, apply a filter, or make an adjustment, it affects only the layer on which you're working. If you get into a snarl over a particularly troublesome layer, you can throw it away and start over. The rest of your document will remain untouched.
Figure 3.1 Layers isolate different parts of the image. (©2005 Regina Cleveland)
You can make the layers relate to each other in interesting ways, such as by poking holes in them to reveal an underlying image. I'll show you some great techniques using this concept in Chapter 13, "Enhancement," and Chapter 15 "Collage."
But first, you need to pick up on the basics—the foundations—of layers. If you've used layers for a while, you might find some of this chapter a bit too basic. On the other hand, you might find some juicy new tidbits.