Digital Focus: How to Clear Up Red-Eye

Clearing Up the Dreaded Red-Eye

Unless you're chief cinematographer for a horror movie, you probably don't go out of your way to include red-eyed monsters in your photos. But in many situations, that's exactly what you get. Red-eye is the common term for what happens when you take a flash picture in low light, such as indoors at a party or outdoors after sunset.

Here's the quick Dr. Science explanation: In low light, your subjects' eyes are fully dilated to make better use of the limited lighting; that makes their pupils, which are quite reflective, huge. When you fire the camera flash, the light reflects off your subjects' retinas, and you've just turned your subjects into extras from a John Carpenter film. Thankfully, there are ways to avoid this ugly effect.

Use the Camera's Red-Eye Mode

If your camera has a red-eye reduction mode--and these days, most do--start there. Set your camera's flash to red-eye mode, and it'll "pre-flash" before taking the actual picture. That means it'll fire several times, almost like a strobe, to force your subjects' pupils to close a bit. That should reduce or eliminate the red-eye effect.

Red-eye mode has its limitations, though. The human eye can't adjust to a change in lighting instantly, so the red-eye control on your camera usually just minimizes the effect--it often doesn't eliminate it.

More frustrating is the delay between when you press the shutter release and when the picture is actually taken. You'll experience a perilous pause while the flash does its little strobe act. If you're not anticipating the delay, your subject may move, or you might jiggle the camera just when the picture is actually taken.

Take the Red Away Automatically

So what if you end up with some red-eye in your photos? Many image editors make it easy to wipe it out in just a few simple steps. Take Paint Shop Pro, for instance. You can download Paint Shop Pro for free.

Load the picture with the offensive red eyes and choose Effects, Enhance, Red-eye Removal. You should see the Red-eye Removal dialog box, which shows both the original image and a preview of the finished effect.

Drag the picture around so you can see the red-eye in the window, and zoom in if you need to get a better view of the red eyes. Click and drag in the window on the left until you've made a circle about the same size as the eye. Then position the circle over the red part of the eye. You should see the effect of your edits in the window on the right.

You can make a lot of additional adjustments, such as varying the eye color, iris size, and even adding a little glint to the eye. When you're satisfied, just click OK to save your new eyes.

Manual Labor

Even if your image editor doesn't have a red-eye removal feature, you can rough it on your own. The trick is simply to paint over the red with a color (such as black or dark blue) that mimics the subject's real eye color. You can just grab a paintbrush from the program's tool palette and start swabbing, but you'll get better results if you select the red region first.

Try the Magic Wand tool. Magic Wands are designed to select all of the neighboring pixels in an image with roughly the same color. And since the eye is full of varying shades of red, this is a great application for the Magic Wand. Select the tool and click the red in the eye. You may need to hold down the Shift key and click several times to "group select" all of the red. Once you're done selecting, just paint over the red with the appropriate eye color and you're done. Take a look at an eye that has been repaired in this way.

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