Compositing with Multiple Images in Photoshop

Often when working with layers, you are not confined to using a single image. I mean, there’s only so much you can do to that family portrait taken down at the local photo studio. But take your family and put them in front of the ruins at Machu Picchu or the summit at Mount Everest and we’re talking about endless hours of fun. When you get the hang of working with several images, you’ll find that it opens a whole new door of creative possibilities. And you’re not limited to just plain old snapshots. You can incorporate type, vector illustrations, and scans of just about anything you can place on a scanning bed. Apply some layer styles, maybe a filter or two, and you’ve got an image worthy of some major wall space.

Copying and pasting images
Earlier in the “Making Layers” section, I explain how to use the Copy, Cut, and Paste commands within the same image or between two different images when you want to fill a new blank layer with content. You can also use the Copy and Paste commands without having a blank layer first. When you copy and paste a selection without a blank layer, Photoshop automatically creates a new layer from the pasted selection. You can go about your merry way and perform all your layer creation by using only those commands. However, I rarely use them when working with multiple images. I prefer the drag-and-drop method described next. The Copy Merged command on the Edit menu creates a merged copy of all the visible layers within the selection.

Dragging and dropping layers
To copy an entire layer from one document to another, simply select the layer in the Layers palette, grab the Move tool, press your mouse button down, and drag and drop that image onto your destination document. Photoshop automatically introduces the dropped layer as a new layer above the active layer in the image. You don’t need to have a selection outline to copy the entire layer. However, if you want to copy just a portion of the layer, make your desired selection before you drag and drop with the Move tool. If you want the selected element to be centered on the destination image, hold down the Shift key as you drag and drop. See the sidebar, “Bypassing the clipboard,” for more on dragging and dropping.

Using the Paste Into command
You may occasionally want to place an image on a separate layer, yet have it fill a selection. That’s where the Edit➪Paste Into command comes into play. This command enables you to insert a copied or cut selected image into a selection outline. For example, if you want to make it appear as if a snake is poking its head out of the opening of a cave, or a possum is emerging from a trash can, Paste Into is your command. Follow these steps to insert a copied or cut selected image into a selection outline:
1. Make the selection on the layer that you want the image to fill.
I’ll call this the destination layer.
2. Select the image that will fill that selection.
I’ll call this the source image. Note: The source image can be within the same image or from another image.
3. Choose Edit-->Copy.
4. Return to the destination layer and choose Edit-->Paste Into.
Photoshop converts the selection outline on the destination layer into a layer mask. The pasted selection is visible only inside the selection outline, like it is peeking out of a hole.