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Ken, Why do some of the people in my pictures have red eye's?

PROBLEM # 4: Red Eye.

The ingredients for the red eye problem are low light, a subject looking at the camera and a flash too close to the lens.

In low light your subject's eye opens the pupil wide to let in more light. You turn on your flash. The subject looks at the camera and you snap the picture. Light fires out of the flash, makes a straight line through the wide-open pupil, bounces off the blood vessels on the back wall of eye(the retina) and reflects straight back into your lens to register on your film or CCD as a big ugly glowing red eye.
The real solution is to raise the flash at least eight inches about the lens. Then the light reflects back from the eyeball at an angle that misses the lens.
This is why wedding photographers have that tall bracket that puts the flash a foot or so above the camera.
Some cameras use "red-eye reduction" but these ususally don't work too well. What most do is when you push the shutter the camera fires a "pre-flash", which is either several short bursts of flash, or a steady light, which makes the subject's pupil contract, then the shutter trips and the real flash fires. Because the pupil is smaller the red eye is reduced but is still there. Red eye reduction causes other problems in the it delays the shutter a split-second, so you usualy miss the shot you wanted. This also tends to make people blink just after the pre-flash, just in time to for the shutter to photograph their closed eyes. It also drains battery juice.

If you have an image that already has red eye there are two ways we can fix this:

  • Buy the "red-eye out" felt tip pens and color the red out. This doesn't always look natural but looks better.
  • Re-touch the image in image-editing programs like
    Adobe Photoshop. This works well but is ususally not cost effective for snap shots.

Ken.

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Have a problem you would like to see addressed in this column? Send me an email at ken@caseycolor.com

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