Once you pick a color using the Adjust­ment Brush’s Color Picker, it’s not really obvious how to reset the color to None (no color). The trick is to click on the Color swatch (near the bottom of the Adjustment Brush options panel) to reopen the Color Picker, then drag the Saturation slider down to 0. Now, you’ll see the X over the Color swatch, letting you know it’s set to None.

 

 

Excerpted from The Adobe Photoshop CC Book for Digital Photographers by Scott Kelby.