Mark S. Johnson Photography

My thanks goes out to Deke McClelland for being a Photoshop genius and pondering things that the rest of us never ponder. I owe this Workbench to his wizardry. While I’m on the subject of gratitude, I’d like to thank both Bradley Bailey and William Krone for allowing me to use their images in today’s tutorial.

In Workbench 169, Selecting Difficult Subjects Like Fur and Hair, I demonstrate a technique for making selections of difficult subjects. The very first step in that technique is to identify the channel that exhibits the best contrast between the subject and the background. The selected channel serves as the foundation for creating a precise selection. Today’s Workbench offers an even more effective approach to picking a channel. In some cases, as you examine the Red, Green, and Blue channels, you may discover that one channel does a nice job of separating part of the subject, say the skin, from the background while another channel separates the hair more effectively. Ideally, you’d like to combine these channels to give you the best of both worlds. Fortunately, there is an answer. It’s called Calculations. Come along as I show you how to put Calculations to work for you.