Unmesh Dinda of PIXimperfect has put together a brilliant educational video on the oft-confusing Divide blend mode in Photoshop. In this tutorial he’ll show you how to use it to remove any color cast, before diving into the fascinating mathematics behind this useful tool.
The video breaks down into two parts, both of which are extremely useful. First, Dinda shows you how to quickly and easily remove any color cast from an image using the ‘Divide’ blend mode and a solid color adjustment layer. Then, he dives into the math behind the blend mode, so you can understand how and why this works.
Part one goes until about the 4:10 mark, but we highly recommend you stick around for the math portion of the tutorial. Understanding how the blend mode actually works—instead of just memorizing one use case, like the color cast example—will open up myriad post-processing possibilities any time you’re editing with color in your photographs.
In fact, that’s the “homework” Dinda gives you at the end of the video: find one more use for the Divide blend mode using this formula as your guide.
Resulting Color = 256 ÷ (Color of Layer with Divide Blend Mode ÷ Color of Layer Underneath)
Dinda regularly creates some of the most fascinating and easy-to-follow Photoshop tutorials on the Web, and this is no exception. Check out the full video up top, and then head over to the PIXimperfect YouTube channel to learn a whole lot more.