What you'll need
Edit a layer mask with the Brush tool
- Click the Add layer mask button in the Layers panel to add a layer mask to the active layer.
- Select the Brush tool and set black in the Foreground color box. (Press D to set the default colors of white and black, and press X to exchange them.)
- Change the size of the brush by tapping the left or right square bracket key on the keyboard.
- Make sure the layer mask is active. (Look for the highlight border around its thumbnail.)
- Paint with black over the image where you want to hide the layer with the layer mask to see the layer below.
Black conceals and white reveals
In a layer mask, black hides what is on the layer with the layer mask, and white shows what is on that layer.
- If you make a mistake and hide too much, press X to exchange the foreground and background colors, and paint with white on the layer mask to reveal the masked layer.
Create a layer mask from a selection
Another way to create a layer mask in a composite is from a selection. When you make a selection and then add a layer mask, the layer mask is automatically white where there was a selection and is black where there was no selection. The black on the layer mask hides the area that was not selected.
- Create a selection using any selection method, like the Quick Selection tool.
- With the selection active in the image, click the Add layer mask button in the Layers panel.
Refine the layer mask with the Brush tool
When you create a layer mask from a selection, you can edit the mask using the Brush tool. This allows you to use a soft-edged brush to create more gradual transitions.
- Paint with black to hide the masked layer, and white to reveal it.
- In the Options bar for the Brush tool, set the opacity to 50% to paint with gray, which will partially hide the masked layer.
Save your work
- Save the image in .PSD or .TIFF format to retain the layers and layer masks.