How to Make Ultra-Difficult Selections Using Alpha Channels in Photoshop

Learning to make selections both precisely and efficiently is a skill all its own, and no method is perfect for every situation. This technique is a great alternative for extremely intricate selections and is both precise and quick in the right situations. Check it out!

Coming to you from Unmesh Dinda of PiXimperfect, this helpful tutorial shows you how to make selections using alpha channels. The technique relies on the fact that every image is composed of three primary colors: red, green, and blue. If we want to separate two things that have an appreciable difference in the balance of these three colors, we hop over to the Channels dialog in Photoshop. For example, in this video, we want to separate primarily green trees and grass from a blue sky so the sky can be swapped out. Thus, we select the blue channel and create a selection mask out of it. From there, there's a bit of refinement to make the mask more precise and pure black and white, but the blue channel does the vast majority of the heavy lifting and makes for a much faster selection than doing it by hand. It's a great trick to have in your arsenal; give it a try! 

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1 Comment

Eric Robinson's picture

Great video.....ta very much.