It’s often said “there are ten ways to do anything in Photoshop” – and that’s probably true. But one aspect of Photoshop that has no real substitute or workaround is using layers. In my opinion, this is a must-have skill for photographers who edit their own images. In fact, many people who begin editing their images in Lightroom have started going back to using Photoshop layers as part of their workflow.
Many image-editing programs require you to work on the original image. In other words, any change you make affects the original pixels. To change this, you frequently have to step back through a series of “undo” commands, or even start over. This is sometimes referred to as destructive editing.
You can use destructive editing in Photoshop by always working on the original, or Background layer. Below is a screen shot in which I’ve applied a sepia tone effect to half the image. If I want to make a change on a single-layer setup, I’ll have to re-start the project, or at least “undo” the work I’ve done:
On the other hand, Photoshop also provides tools for working on multiple layers, which can be referred to as non-destructive editing.
Quoting from an article in PC Magazine: “in a layered imaging program, objects are placed in separate layers and can be freely moved under and over each other. Objects can always be added, and any object can be removed or changed without affecting the others.”
For example, you can add one image to another on a layer or add type or a graphic element.
This illustration shows how a stack of layers can each have a different color adjustment or effect
Another way to think of layers is that they are like slides (transparencies) stacked on top of each other, and each layer can contain a different adjustment, style, or special effect. Stacked like this each layer can affect the layers below it in the stack.
Viewed together, the layers appear to be a single image. However, you can edit any layer at will without touching the pixels in another layer. Here’s an example:
Each layer can be made visible or invisible, be adjusted independently, or even discarded without affecting the others. One can apply levels or curves adjustments, move a layer, retouch, and more. It is easy to return to an image, adjust one layer, and go back to printing or other production tasks. Very efficient!
You can change the opacity (transparency) of a layer to increase or decrease its effect on layers beneath it.
Going back to the edited black and white image, I've added a color effect to a layer, and I've added my copyright notice as a text layer.
This article is just an introduction to the concept of using layers in Photoshop. Learning how to use layers to their full potential takes a bit of persistence and practice.
One very useful source for tutorials is the Help screen at the top of your Photoshop screen! Adobe provides hundreds of superb tutorials and lessons via on-screen and online text and video files. Next time you open Photoshop, take a look – you’ll be pleasantly surprised.
Don’t worry about whether you have Photoshop CS3, CS4 or CS5. Layers work in all these versions, and earlier ones, too.