Getting the Redeye Out
Using Photoshop 6.0
By Don Skiff
| To remove the red from eyes in photos of people (usually shot with flash-on-camera), I used to paint over the red with near-black, a difficult technique that usually proved unsatisfactory. Here’s a technique borrowed from Dan Margulis in Electronic Publishing magazine, February, 2002: |
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| Zoom in close to the eye and use the lasso tool to select the pupil. You can include some of the iris, but not the eyelid. |
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| Press CTRL-1 (yes, that’s a one) to display the red pixels only. Notice that the red is pretty bright. Not only do we have to change the color, we must reduce the luminance. Leave the selection in place and go to the next step. |
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| Choose Image—Apply Image. Change the Channel to Green and the Blending to Darken. The Opacity should be 100%. Click OK. |
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| Press CTRL-~ (that’s a tilde) to restore the image to color. Here’s the result. Slick, eh? |
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| Now do the same with the other eye. |
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| Voila!—go on with the rest of your retouching! | |
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In our example, the low resolution of the image (because we enlarged it to show up here) caused some red to show in the iris. That doesn’t ordinarily happen if the image has not been enlarged so much. If it does in your work, back up a couple of steps and be more accurate in the lasso selection, including the entire iris but not any of the lid. What if it didn’t work? (See below for alternatives.) |
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| What if it didn’t work? | |
| Sometimes the reflected light from the retina is extra bright, even to the extent that it saturates the film or CCD. In that case, the "red eye" is more white than red. The other colors (blue and green) are also present, so that when you use the above procedure the pupil does not come out near black. Here’s one that came out blue! | |
| Figure 1. The original photograph. Both pupils are obviously very wide, allowing a lot of light through. Notice that the eye on the left is more orange than red. |
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| Figure 2. The result of the "standard" treatment from page 1. (Incidentally, the other eye responded perfectly to the standard treatment.) |
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| Figure 3. The result of inverting the red image in Image/Apply Image (after the standard treatment). We did try applying blue instead of green in the standard treatment, but without effect. Here, only the blue shows. Notice also that the highlight is also gone. |
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| Figure 4. Then we displayed the blue image (Ctrl-3) and applied red to it, resulting in the darkening of the blue. We added the highlight back in with a very small airbrush. |
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The bottom line, then, is that not all tricks work equally well in all cases! You may have to experiment. That has two benefits—you find out what works and you learn a bit more about how colors respond. My biggest gain was in getting acquainted with Image/Apply Image. I’m sure there are other uses for that feature, but this one made it valuable to me.
Thanks to Dan Margulis for getting me started, and to Mike Sivak (my instructor at Washtenaw Community College) for encouraging me in this.
Don Skiff
March 27, 2002