Digital Focus: Remove Red Eye, All About Enlarging

Feature: Eliminate the Evil Eye Digitally

Remember those evil Dobermans in The Omen? That's what I think of whenever I see a photo of someone with flash-induced red eye. Red eye, of course, is the phenomenon that occurs when the camera flash reflects off your subject's retina. This happens when the pupils are wide open because you're shooting in the dark or in low light. You probably know how to minimize red eye--by using the red-eye reduction mode on your camera, for instance. But what happens if you already have a few photos with red eye? Like a human bottle of eye medication, you can get the red out yourself. All you need is your favorite image editor.

Automatic Red Eye Removal

The easiest way to eliminate red eye is by using your image editor's automatic red eye tool. So before you get dirty doing it the manual way, check to see if your software has a red-eye removal feature. Some tools are completely automated: Just draw a box around the eyes, and the software does the rest. Paint Shop Pro, my program of choice, has a great semi-automated process for eliminating red eye.

Start by opening a photo that includes someone with a case of the Evil Eye. Use my sample image if you'd like--it's got two cases of the worst red eye I've ever seen.

In the Paint Shop Pro menu, choose Effects, Enhance Photo, Red-Eye Removal. You'll see the Red-Eye Removal dialog box, which has a preview window on the right and an editing window on the left. Start with the kid on the left--he'll be a bit easier to work on, since he doesn't have a pair of glasses getting in the way. Drag the image in the preview window around until you see a red eye in the middle of the frame. (Don't try dragging the left side around, since that's where you'll "draw" on the eyes.) Once you can see the eye, use the zoom buttons, which are located in the middle-right below the preview and editing windows, to zoom in until the eye fills as much of the frame as possible.

Make sure that the Method is set to Auto Human Eye and select a proper hue and color. Once everything is ready, go to the left (editing) window, click in the dead-center of a red eye, and drag the mouse outward until the circle expands enough to cover as much of the red as you can without going beyond the natural bounds of the iris. Check your work in the preview window on the right. Keep in mind that some of the surrounding reddish tinge you'll see at full zoom will be unnoticeable in a normal view. You can resize and re-position the eye if needed.

Repeat the process for the other eye. When both eyes are finished, click OK to close the Red-Eye Removal dialog box and keep your changes.

The Old-Fashioned Way

If you're using an image editor that doesn't have a red-eye remover, you'll have to take the red out yourself. It's easy, though, and it doesn't even take a particularly steady hand.

There are a few ways to tackle the problem. For instance, in Paint Shop Pro, you could zoom in and use the Magic Wand tool to select the red in each eye and then paint the selections a color that looks natural for that subject--blue or black, for instance.

But if you've got a lot of images to fix, I have an easier solution: Load the offending image and zoom way in so that an eye fills much of the screen. Choose the standard Paint Brush from the toolbar and make sure that its shape is set to round in the Tool Options dialog box. (Right-click on the tool to bring up a list of options, then pick Tool Options.) Set the size--the brush's diameter--to approximately the size of the red in the photo. In the sample photo I've supplied, 8 pixels is just about right.

Now set the foreground and background colors of the brush. Go to the rectangular color palette on the upper-right edge of the screen and right-click in the bottom left of the rectangle to set the background color to black. Left-click in the upper right to set white as the foreground color.

Finally, position the brush over a red eye and stamp it black by right-clicking. Go back to the Tool options dialog box and change the brush size to about 2 pixels, then stamp with the left button to add the white glint in the center of the eye. That's all there is to it. The results aren't perfect, of course, but they'll turn a throw-away photo into something you might want to keep.

Notice that you don't have to do a perfect job to create a fairly convincing eye--the detail is so small in most pictures that simply eliminating most of the red is enough to dramatically improve the picture.