If you want to do much more than adjust the color or brightness of an image in Photoshop, you're probably going to have to use layers. A lot of people are intimidated by layers, mainly because no one's explained to them what they are and how they work. Once you know that, they're really easy and not intimidating in the slightest. So since every so often someone I know asks me how to do something that requires layers, and then I have to explain layers all over again, here's the simplest explanation I can think of for what they are, how they work, and why you shouldn't be afraid of them.
Simply put, layers are basically a virtual stack of images, one on top of another, and your pov is that of a person standing over them and looking directly down at the top one. By varying the opacity of each layer, you can see the image(s) lying underneath, sort of like the images are printed on plastic that you can either make clear, like a slide, or opaque, like paper. That's simple enough, but you really have to think of the stack as a cross-section when you're working on it, and that's where it can get a little confusing for some people.
Think of your image file as a sandwich. When you open your initial image, say napoleon.jpg, that's automatically your first layer. It's the bottom slice of bread. If all you want to do is resize, crop, or make a few tweaks, then you're solid; all you need or want is that one slice of bread. If, however, you want to do anything more to it, you'll need to create more layers, which is like making a sandwich, in that every new layer is a new ingredient in the sandwich - ham lies on the bread, cheese lies on that, then a tomato, then lettuce, and finally, the last piece of bread. The list in the layers window makes it easy, because what's at the bottom of the layers window is what's at the bottom of your sandwich (which is really your stack of images). The more layers you have, the more ingredients in your sandwich. You can rearrange the layers, too. So if you decide you want your cheese on top of your tomato, that's no problem. All you have to do is use your mouse to drag that layer up, so that it's above the tomato on the list of layers, or drag the tomato down, so that it's beneath the cheese in the list of layers. If you can't see your list of layers, then go up to the menu at the top of your Photoshop window and click "Window," then choose "Layers" out of the droplist. You can also hit your F7 key.
If you're going to use a lot of layers in your image, I recommend labelling each one with what it is. If you're only dealing with a few layers, that's not a big deal, but if you've got upwards of 12 going, it's a lot easier if you tell yourself what each one is. All you have to do is doubleclick the name of the layer in the layers window and type over it with whatever name you want.
So say I open my picture of Napoleon. I can see a tiny version of the image in the Layers window, and Photoshop has named it "Background." (I can't change that. I can't drag it around, either. You have to duplicate the layer to do that, and that's not part of this lesson, but hey - set off on your own. I encourage it.)
He's my bread. Then I decide I want to add Napoleon's canine brother, Razzle to the image. I have Razzle in the shot I took just before Napleon came to pose for me, but I don't have them together.
So I open the image of Razzle, and then clicking the little mouse symbol (looks like an arrow with a fancy plus sign) in my toolset, I click and drag the image out of the Razzle window and over to the Napoleon image window.
The picture of Razzle is now my second layer, the ham. Photoshop names it "Layer 1." I doubleclick "Layer 1" and change it to "Razzle." The two images don't fully match up, so I need to move Razzle around a little. To do that, I just click and drag to move it around, the same way I dragged it overtop of Napoleon. In order to place it so the two images match up, I need to be able to see through the Razzle layer to the background layer. Up at the top of my Layers window in the righthand corner, it says "Opacity." Next to that is a little box that says 100% and has a little triangle/arrow next to it. I click the arrow, and a slider appears underneath it. I use my mouse to move the slider to the left until I can see through the Razzle layer to the background layer. If I slide it all the way left, the Razzle layer disappears. I find a percentage that allows me to see both layers well enough to line up the sofa cushions so that it looks like Razzle is standing behind the sofa while Napoleon sits in front of it. Now all I have to do is erase around Razzle, so I just use my eraser tool and erase everything in the Razzle layer except for Razzle. I find this easier to do while the top layer is still kinda transparent. When I'm done, I move the slider all the way right again, so Razzle is solid and doesn't look like a ghost dog.
Now I can see everything in the background layer, and there's Razzle, leaning on the back of the couch from behind it. At this point, I save my image file and name it something else, so if I need to, I can reopen the original image. When you're working with layers, I advise you to save, and safe often. You should do that anyway, but especially with layers or lots of effects.
At this point, my sandwich consists of 2 layers, the bread and some ham. I can move Razzle around wherever I want and do whatever I want to that layer. If I decide to move him to the other side of the sofa, I can (just click and drag), or I could make him black and white and leave the bottom layer in color (you do that just like you would normally). So long as the Razzle layer is the one highlighted in the Layers window, I can change it around without affecting the bottom background layer. If I want to change to the background layer to make some changes to it, all I have to do is click it once in the Layers window to tell Photoshop I want to work on that layer. (Whichever layer is highlighted in your list is the one you are currently working on. That's kind of frustrating sometimes, when you forget to change layers and you can't figure out why nothing is happening to the layer you think your working on, or when you accidentally erase something you didn't mean to erase, but just hit undo and then change layers.)
Now, I decide that I want to make this image a monochrome, sepia image. Instead of changing both layers to black and white and then having to colorize them separately, I'm going to flatten the layers. All that means is I'm going to merge the layers so that they're one single image. Sort of like smashing the ham into my bread so that it becomes part of the bread. To do that, I go to the menu at the top of the Photoshop window and choose Layer. Way down at the bottom of the dropdown list, second from the bottom, I click "Flatten Layer." Now I'm back to just having one layer, the background layer. Once I do that, I can't make any changes to Razzle without also changing the background Napoleon layer, so make sure you've done everything before you flatten your layers. It's a real pain to get 10 more steps down the road and then realize you left something undone before you flattened your layers. Since I've done all I need to, I go ahead and flatten the layers. Then I convert the image to black and white, colorize it, and I'm ready to progress with more layers.
I'm not going to explain everything I do to this particular image, since it's all a matter of choice, but suffice to say, I duplicate 2 layers and do different things to each layer and then flatten the image again, so I'm back with you at 1 layer. I decide I want to use my brush set to stamp some flowers on the image. I go to the top menu and then mouse over "Layer" in the droplist. That gives me a submenu, the very first choice of which is "New." I mouse over that and get another submenu, the first choice of which is "Layer..." meaning it will open a new layer. (You can also type shift+control+N.) I click that, and a dialogue box pops open that says Layer 1 and gives me several options. At this time, I can leave it titled Layer 1 and just click okay, or I can change the name of the layer to something like flowers 1. I'm going to leave it layer 1 for now. I don't care about the other options, so I just click okay.
Now I select the brush I want and "stamp" the image. I suggest you open a new layer for every brush you want to use, as that makes it a lot easier to fix mistakes and move things around. I choose a flower brush I like from my own personal stash of brushes, and "stamp" the image in white, making sure my brush is set for 100% opacity and flow. Since I decided to "stamp" across the bottom, I name the layer with that brush on it "bottom." (coz i'm creative like that, yo)
I open another layer and "stamp" in orange across the top. Now I have 3 layers. I decide I want to add another color of brushes to the bottom, so I open one more layer and "stamp" 2x in orange, for a total of 5. Since I don't like really strong brushes, I adjust the opacity of my 4 brush layers in the layer window, just like I did the Razzle layer above. Now I have my bread, ham, cheese, lettuce, and tomato. Finally, I decide I'd like to put a border around my image, and since I have a cool border layer I got from
Vibe (and I, myself, suck at borders), I decide to use that. I open that file, and drag the image onto mine.
The border image is of a different resolution than mine, so I have to resize it to fit. I go to the top menu and choose Edit, and from that droplist, I choose free transorm. From there, it's a matter of dragging and resizing, and then you click the checkmark symbol on the right side of your toolbar to tell Photoshop that you meant to do that. This particular border image always places itself directly on top of the background layer of whatever image file I drag it into, like maybe it's some mustard trying to squeak in there. But I've got the flower brushes (my ham, cheese, tomato, etc.) in layers on top of my background layer of bread, and I think I want the border layer to lie on top, like the second slice of bread when I make a sandwich. (And seriously, mustard on a ham & swiss sandwich? Gross!) So I go to my Layers window, where the Vibe image layer is already highlighted, and drag that up to the very top of my layers list, so that now, I have my top piece of bread (and no mustard).
Only, hmm. Maybe I do like mustard on my ham and swiss. The vibe layer looked kinda cool with my flowers all growing on top of it. I like that. I just drag the vibe layer back down, so that it's sitting between Flowers 1 and the Background, and I'm finished. I like the look of that, so I hit save, then I go up to the top menu and choose Layer, go all the way down to the bottom of the droplist, and click Flatten Layer. My image is done. All I have to do is save it as a jpg, and I'm finished!
"But Katie," I hear you say, "what if I decide I don't like all the flowers I used on my image? What if it looks too cluttered?" Well, now, I kinda agree. We used too many flowers, didn't we? All you have to do is open the psd file, and there are all the layers, still sitting right where we left them. If you click the little eye icons to the left of each layer, you can turn the layers on and off (eye showing means on, eye invisible means off). Pick and choose which layers you want to show up, and then you can either right click and delete layers you don't want, or just leave them turned off, in case you think you might want them back again later. When you have the layers as you like them, you can save the psd, flatten it, and the just re-save as a jpg. You're finished.
Now see? Layers are not that hard, afterall. :)
Next tutorial: textures
Labels: photoshop, tutorials
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