Advanced Editing

Introduction to Layer Masks

Written by Digicamhelp Editor

If you’ve ever worn a mask, you’ll understand the basic concept of Layer masks: everything is visible except what’s behind the mask. This technique is used to combine multiple images into a single photo as well as make color, tonal and other corrections.

Once you’ve gotten familiar with the basics of layers in your photo editing program, it’s time to move on to layer masks. Don’t be intimidated by the name – a layer mask is simply an image layer that covers – or masks – the image beneath it.

Color mask

You can then use your editing program’s drawing tools to remove parts of the mask and reveal the image underneath. You can also select portions of the layer mask with any of your editing program’s selection tools, and then adjust the selection’s opacity to reveal and blend the background image into the layer.

The following tutorial demonstrates how to create a black and white photograph with a single object in color through the use of a layer mask.

How to create an effect using a layer mask

Fruit bowlTo create our selective color photo, we first open a full color photo of our still life. For this tutorial, we’re using Adobe Photoshop Elements.

Layer maskElements makes it quick and easy to create a layer mask. In the layers dialog box, click the half-white, half-gray circle icon.

On the drop down menu that appears, select Hue/Saturation. The Hue/Saturation dialog box will appear. Slide the Saturation slider all the way to the left to remove all color from the layer. Click OK.

You now have a black and white layer mask on top of the color photograph.

Fuller versions of Photoshop have a separate layer mask icon while other programs may require you to create a layer first before converting it to a layer mask.

Drawing over a mask

With your layer mask in place, you can use the brush tool to draw over the mask.

Drawing over the mask in black reveals the background image. Drawing over the mask in white covers the background image once again.

Apple brush

Zoom in on an object that you would like to appear in color. Select the brush tool and set it to black, then adjust the size of the brush to fit comfortably within the object.

Carefully draw over the object to reveal the color underneath. If you stray outside of the object, you can fix your mistake by switching the brush to white and drawing over stray marks.

Flatten and save

Once you’re satisfied with your work, flatten the image and save it.

When you flatten an image, all visible layers are merges into the background. This reduces the overall file size of the image. Choose Flatten Image from either the Layer menu or the Layers palette More menu.

To retain the original image and all the layers, use the Save As command. Select a file type, such as jpeg, gif or tiff.

Layer masks can also be used to blend parts of two photos together or insert an object from one photograph into another.