What Is A Layer?
Layers are usually quite puzzling to those who are just beginning to learn Photoshop Elements, so let’s start by clearing up the confusion over layers once and for all.
(Hint: You already know what a layer is—you just haven’t applied your knowledge to digital layers yet!)
Video 02-01: What Is A Layer? (6:18)
In this lesson, I'm going to help you wrap your mind around the concept of layers, because this tends to be quite puzzling to those who are just beginning to learn Photoshop Elements.
First, let's start with physical layers. Let's say you have one piece of paper lying on your kitchen table. That would be one layer of paper. Let's say you put another copy of the same paper on top of the first one. You now have two layers. Let's add a third layer of paper, but we'll use a different kind of paper.
Next, you place a photo on the paper because you're planning to create a card. Is the photo a layer? Well, we wouldn't normally call it a layer, it's just a photo. But if you think about it, it is a layer. Layers above other layers cover up whatever is below them. So here the photo covers up some of the paper.
Now we have a few random items we've gathered: a small bow, a sticker, and a little flower from the craft store. Are these layers? Well, again, we wouldn't call them layers, we would call them craft items or elements. So let's use all these items to create a card.
Here's my finished card. Are the craft elements a layer now? Yes, definitely, there are a layer on my project, which is a card. The order of layers is important. If I place the green paper above all the other card layers, it will cover them up. So let's put that back again.
Now let's create this same card digitally. I'll use the same photo, only in digital form. To toggle through all the open images for my card, I'll use the shortcut which is Ctrl Tab in both Windows and Mac. Here's the paper with print, the green paper, some tape, a sticker, a bow, a flower, and back to my photo. Recognize all of these? They're the same kind of thing used in paper crafting, but they're in digital form. Each one of these files has only one layer.
Now let's look at the finished card where I've combined and arranged all the individual layers into one document. Each item on my card appears in the Layers panel as a separate layer. The term we use for this is compositing. According to the dictionary, a composite is something that is made up of various parts or elements. Think about it. Just as each physical item, the papers, photo, tape, sticker, bow, and flower became a layer on a card on my kitchen table. So every digital piece of paper or photo or element in this document is an individual layer. These layers are digital instead of physical, but in many ways they act like true physical layers.
I can rearrange a layer if I want by clicking and dragging it to a new spot in the Layers panel. But just like physical layers, digital layers hide the layers below them. So I'll click on the Undo icon in the Taskbar to return the layer to its original spot. Digital layers have some advantages that real layers don't have. I can click on the Visibility icon to the left of the thumbnail to temporarily hide a layer, but it's still there and all I have to do is click again in the same spot to reveal the layer. I sure wish I could do that with the paper piles that accumulate on my kitchen table!
Digital layers that only cover part of the document will have transparency around them. You can see this better if I press the Alt key in Windows or the Option key on a Mac and click on the eye of a layer. Alt or Option clicking on the eye is a keyboard shortcut that hides all the other layers except this one. See how the thumbnail corresponds to the actual layer on the page? To make all my other layers visible again, I'll press Alt or Option and click on the eye again.
With physical papers and elements, I can glue or tape them together which essentially turns them into one layer. The digital equivalent to gluing layers together is to flatten layers. I can click on the icon in the upper right corner of the Layers panel to get a flyout menu and choose flatten image. Now I have only one layer. If I ever want to make a change, though, it's hard to do after it's been flattened.
The good news is that you don't need to flatten your layers to keep them all in place. In Photoshop Elements your layers won't move or get scattered by a toddler or chewed on by the dog. So I recommend that you don't flatten your image. I'll click on the Undo icon and now all my layers are back.
So how do you get all these layers into the Layers panel so that they show up in one document? I'm glad you asked that question! In the very next lesson I'll teach you the number one way to add layers to the Layers panel, but before we move on, there's something I recommend you do, and that's to adjust your layer thumbnail size and position. So go ahead open Photoshop Elements and click on the tab of the Layers panel to activate it.
Navigate to the practice files for lesson one and open this document called Layers-Demo.psd. Notice how the thumbnails appear. The smaller the object, the less visible it appears in the Layers panel thumbnail, because the thumbnail includes all the transparency as well as the object. To change that click on the icon in the upper right corner of the Layers panel to get a flyout menu and choose Panel Options. When the dialog box comes up, choose the largest thumbnail size. Under Thumbnail Contents, choose Layer Bounds instead of Entire Document and click OK. This will cause the thumbnail to show the object on that layer with minimal transparency. In my opinion, this is a much better view that allows you to actually see what's on the layer.
So now that your Layers panel is set up, we'll learn more about how to composite multiple layers in the coming lessons.