FREE Luminosity Masks
This FREE action creates 7 Luminosity Masks within your “Channels” palette. After loading this action, you can select Highlights, Shadows, and Midtones with the click of a button to isolate them as you work on an image. This action was created in Photoshop CC. (It has not been tested on earlier versions of either Photoshop or Elements.) The video below explains how to use Luminosity Masks, after downloading and loading this action into Photoshop.