Adobe Photoshop CS4 - Manual (Page 332)

325 USING PHOTOSHOP CS4
Layers
Last updated 1/10/2010
Add layer masks
When you add a layer mask, you need to decide if you want to hide or show all of the layer. Later, you’ll paint on the
mask to hide portions of that layer and reveal the layers beneath. Or, you can create a layer mask that automatically
hides a portion of the layer by making a selection before creating the mask.
Add a mask that shows or hides the entire layer
1 Make sure that no part of your image is selected. Choose Select > Deselect.
2 In the Layers panel, select the layer or group.
3 Do one of the following:
• To create a mask that reveals the entire layer, click the Pixel Mask button in the Masks panel, or click the Add
Layer Mask button in the Layers panel, or choose Layer > Layer Mask > Reveal All.
• To create a mask that hides the entire layer, Alt-click (Windows) or Option-click (Mac OS) the Pixel Mask
button in the Masks panel, or Alt-click (Windows) or Option-click (Mac OS) the Add Layer Mask button, or
choose Layer > Layer Mask > Hide All.
Add a layer mask that hides part of a layer
1 In the Layers panel, select the layer or group.
2 Select the area in the image, and do one of the following:
• Click the Pixel Mask button in the Masks panel, or the New Layer Mask button in the Layers panel to create
a mask that reveals the selection.
• Alt-click (Windows) or Option-click (Mac OS) the Pixel Mask button in the Masks panel, or the Add Layer Mask
button in the Layers panel, to create a mask that hides the selection.
• Choose Layer > Layer Mask > Reveal Selection or Hide Selection.
Apply a layer mask from another layer
❖ Do one of the following:
• To move the mask to another layer, drag the mask to the other layer.
• To duplicate the mask, Alt-drag (Windows) or Option-drag (Mac OS) the mask to other layer.
Edit a layer mask
1 In the Layers panel, select the layer containing the mask you want to edit.
2 Click the Pixel Mask button in the Masks panel to make it active. A border appears around the mask thumbnail.
3 Select any of the editing or painting tools.
Note: The foreground and background colors assume default grayscale values when the mask is active.
4 Do one of the following:
• To subtract from the mask and reveal the layer, paint the mask with white.
• To make the layer partially visible, paint the mask with gray. Darker grays make the level more transparent, lighter
grays make it more opaque.
• To add to the mask and hide the layer or group, paint the mask with black. The layers below become visible.
To edit the layer instead of the layer mask, select it by clicking its thumbnail in the Layers panel. A border appears
around the layer thumbnail.