How to Use Quick Masks in Photoshop

What Quick Mask Mode Does

Quick Mask is a different way to look at a selection. Press Q (or click the button below the color swatches in the toolbar) and the document tab reads “Quick Mask/8,” the layer thumbnail tints red, and any active selection appears as a red overlay. Press Q again and whatever is in the mask becomes a regular marching-ants selection. The red areas are not selected; the clear areas are.

Paint a Selection with the Brush in Quick Mask Mode

While Quick Mask Mode is on, every tool becomes a selection tool. Paint with black and the stroke shows up as red, meaning that area is being removed from the selection; paint with white to add to it. Aaron draws a quick shape with the Brush Tool, presses Q, and it turns straight into a selection. It works the other way too: make a rough Lasso selection, press Q, and you get a clear picture of exactly what’s inside it.

Refine a Color Range Selection

Select > Color Range is a fast way to grab the text on a subject’s shirt, but it usually picks up stray areas of the background as well. Press Q to enter Quick Mask Mode and see everything that got selected, then paint black over the parts you don’t want. Press Q again and only the logo remains selected, ready for a Hue/Saturation adjustment layer with Colorize turned on to recolor it.

Run Filters on a Selection

This is the part you can’t do any other way. Draw an Elliptical Marquee around a face, press Q for Quick Mask Mode, then go to Filter > Blur > Gaussian Blur. You’ll see the edge of the mask soften in real time, which is a far more visual way to feather than the Feather dialog. Press Q to return to a selection and add a Curves adjustment layer: the brightening fades out gently instead of stopping at a hard oval edge.

From Quick Mask Mode to Layer Mask

Because an adjustment layer picks up the active selection as its layer mask, any selection you blur or paint in Quick Mask becomes a finished, soft-edged layer mask the moment you add the adjustment. Hard-edged selection in, polished mask out, with nothing but Q and a filter in between.

Quick Reference

• Q toggles Quick Mask Mode on and off.
• Red = not selected, clear = selected.
• Paint black to remove from a selection, white to add.
• Filter > Blur > Gaussian Blur in Quick Mask to feather a selection visually.
• Add an adjustment layer with the selection active to turn it into a layer mask.