Ever shoot a fabulous landscape, only to notice that backlit branches, trees, or mountains have a purple edge where they meet the sky? Or that one side of a backlit object is cyan and the other is red? The purple stuff is called fringing, and the two-color ugliness, chromatic aberration. Both are so common in digital pictures that we tend to ignore or accept them. But getting rid of them will make your photos look much cleaner and more professional. Here’s how to lose both types of unnatural tones from your edges.
1. If you shoot RAW , get rid of as much fringing as you can in Adobe Camera Raw before bringing your image into Photoshop. After you’ve done the usual tweaking of exposure, white balance, and the like in ACR, head over to the Lens Corrections tab (fourth from the right). Chromatic Aberration is first among the options. Since this photo is mainly plagued with fringe, use the Defringe pulldown menu to select Highlight Edges. Sometimes this does the trick, but often a picture needs more work. If so, head to Photoshop to get rid of the rest.
2. When you’re working on a JPEG or TIFF (converted from a RAW ) file, fix Chromatic Aberration in Photoshop using the Lens Correction filter. Find it under Filter > Distort > Lens Correction. The first thing to do when you get into the tool is uncheck the Show Grid option at the bottom of the screen. This will help you see what you’re doing. Magnify one of your more troublesome areas, and use the Chromatic Aberration sliders to get rid of it. Most of the time, you’ll need to move the sliders only slightly. This tree trunk has a bit of cyan fringing, so move the Red/Cyan a few notches to the right to hide it.
3. Automatic tools and sliders can only go so far. When discoloration remains, you have to get in there and remove it manually. Duplicate your Background Layer, then zoom in on the purpleringed branches. Type the letter O on your keyboard for the Sponge tool (if you don’t see it, it’s hiding under Dodge or Burn in the main Toolbar). Then, in the Options Bar, choose Mode: Desaturate. Paint over the purple to start cleaning up the branches. Don’t worry if you have a messy, heavy hand. Because the branches are almost in silhouette, they’re nearly monochrome anyway. Just be careful not to desaturate any leaves. If you accidentally lose color you want, add a mask to the layer and paint with black to reveal the properly toned Background layer below.