101. Group and Organize Layers
Before You Begin
91 About Layers and the Layers Palette
92 Create a New Image Layer
96 Simplify a Layer
102 Merge or Flatten Layers into One
If you have multiple layers that are related and that require similar adjustments, you can group (link) the layers together in the image. When layers are linked, you can move their contents as a unit using the Move tool. You can also resize, skew, and distort the layers as if they were a single layer (again, using the Move tool). See 99 Move, Resize, Skew, or Distort a Layer. For example, you might want to resize several layers, each containing a single person, so that the group of people is more proportional with the background scene. If the layers containing the people are linked, you can focus on resizing the group as if they were one layer. You can also copy and paste linked layers as if they were one. Layers that are linked together do not have to reside next to each other in the layer stack.
In addition to linking layers together, you can group them. The purpose of grouping, however, is not the same as linkingyou group two or more layers together for the sole purpose of creating a clipping mask. The purpose of a clipping mask is to block the data on a particular layer or layers from blocking the data on the layers below. See 163 Mask an Image Layer.
To remove a layer from an image, select it in the Layers palette and then click the Delete layer button at the top of the Layer palette or choose Layers, Delete.
Whether or not layers are linked, you can still work on them as separate elements of your image. As you know, layers on the top of the layer stack block the data on layers below. So arranging layers properly in the Layers palette is critical to the way your final image looks. For example, a tree on the layer below a layer with a group picture can be made to appear in front of the group if you move the tree layer above the group layer in the Layers palette. You can move any layer except the Background layer, because it is locked. (To move the Background layer up in the layer stack, convert it to a regular layer. See 95 Convert a Background Layer to a Regular Layer and Vice Versa.)
Move Layers in the Layers Palette
Open an image in the Editor in Standard Edit mode and save it in Photoshop (*.psd) format. On the Layers palette, click a layer to select it and drag it up or down the stack until it is placed in the desired location.
As you drag a layer in the Layers palette, a location line displays to show where the selected layer will be inserted in the layer stack when you drop it. When the layer is located in the stack where you want it to be, release the mouse button.
Click to select a layer in the Layers palette. Click in the column to the immediate left of the layer icon for the layer you want to link to the currently selected layer. A Link icon (a chain) appears next to the linked layer indicating it is linked to the active layer. You can click the Link icon in front of any other layer to add it to this linked group.
To unlink layers that are linked together, click either layer in the Layers palette. The Link icon appears on the other layer(s) it is linked to. Click this Link icon on any of the linked layers to turn off linking.
Change Linked Layers
With layers linked together, you can perform group functions on them. You can move, resize, skew, or distort the linked layers and even copy or paste their data as one. See 86 About Copying, Cutting, and Pasting Data Within a Selection, 99 Move, Resize, Skew, or Distort a Layer, and 106 Rotate an Image or Layer. Here, I linked the Halo and Pillow layers together so that I could move them as a unit beneath the baby's head.
When you're satisfied with the image, save the PSD file. Then merge the layers together and resave the result in JPEG or TIFF format, leaving your PSD image unflattened so that you can return at a later time and make different adjustments if you want.