Shape Masks

Shape masks work pretty much like type masks. To create one, all you need to do to is clip an image layer to the shape layer underneath it in the Layers palette. You can change the crop area nondestructively by moving the image or transforming the shape.

Let’s take a step-by-step look at how this image was created.
1. Open the image that you’d like to crop inside a shape. In this example, the image is a landscape of Ireland. Press F/Ctrl+A to select the whole image; then press F/Ctrl+Shift+J to cut the selected image from the Background layer and place it on a new layer above in the Layers palette. Rename the layer accordingly (Ireland in this example).

2. To create the shape, begin by pressing Option/Alt+[ (left bracket) to activate the Background layer. Then press U to access the Shape tool. In the Options palette, click the Shape Layer and Custom Shape tool icons, and then select a shape from the Custom Shape Picker (in this example, I selected the Shamrock shape from the Nature library). Click and drag in the document window to draw the shape. Hold down Shift as you click and drag to constrain horizontal and vertical proportions. As soon as you begin drawing with the tool, a new shape layer is added to the document above the Background layer.

3. Create a group by Option/Alt+clicking between the Shape layer and the image layer above it in the Layers palette. The image is automatically cropped inside the shape. If you’d like to adjust the crop, you can select the image layer and use the Move tool to  reposition the image inside the shape.

4. You can add some dimension to the Shape layer by applying a layer style to it. In the example shown here, the Translucent Glass style from the Glass Buttons style set is applied and a dark green drop shadow is added to it.

Move Shapes as You Draw Them
Holding down the spacebar as you click and drag with the Shape tool allows you to move the shape in the document window as you draw it.

5. I then added a green Solid Color adjustment layer to the top of the layer stack in order to add a color tint to the image. To add it to the clipping group, I Option/Alt+clicked between the Solid Color layer and the grouped image layer below it in the Layers palette. Now, by adding the color layer to the group, only images within the group are affected by the color overlay, and I don’t have to worry about layer order, should I decide to add any text or other images to the composition. Last, I changed the blend mode of the S

6. To add some text to the graphic, I extended the canvas by using the Canvas Size dialog box (Image --> Canvas Size). Text is generally best added in a layout application such as InDesign, QuarkXPress, or Illustrator (for single page layouts); however, in this instance, I added the text in Photoshop for comping purposes only, or for position only (FPO).