You can add a mask to a layer and use the mask to hide portions of the layer and reveal the layers below. Masking layers is a valuable compositing technique for combining multiple photos into a single image or for making local color and tonal corrections.

• About layer and vector masks
• Add layer masks
• Edit a layer mask
• Select and display the layer mask channel
• Disable or enable a layer mask
• Change the layer mask rubylith color or opacity
• Add and edit vector masks
• Unlinking layers and masks
• Apply or delete a layer mask
• Load a layer or layer mask’s boundaries as a selection
• Mask layers with clipping masks
• Combine multiple images into a group portrait