Fact of the Day
Ok, I may have made it sound worse than it is, but it's not too far from the truth. When something as bright as a camera flash is applied, the retina reflects the light from the back of the eye. In the eyes of animals, the retina has a reflective coating. This reflective coating explains what happens to a deer's eyes in headlights, they reflect the headlights back with full intensity.
Humans lack this coating and therefore expose the blood vessels in the back of the eye. A camera flash actually reflects the red of the blood back out of the pupil. This is why there is more red if the pupil is larger.
A camera with red eye reduction is not the best way to go about avoiding demonic pictures. All this feature does is add another flash to the photo-taking sequence in order to make the pupils smaller. They are often sill red. The trick lies in the angle of the flash on the eye. Unfortunately, people are trained to look directly at the camera. If it is at all possible to have the flash come from a slightly different angle, the problem should be solved. Also, more external light minimizes the camera flash in the hierarchy of light on the subject.
"Retinoblastoma Awareness." Joey Bergsma. 16 Nov. 2008 .
Soniak, Matt. "mental_floss Blog: Why Do We Get Red Eye in Photos?." mental_floss magazine - Where Knowledge Junkies Get Their Fix. 24 Oct. 2008. 16 Nov. 2008 .
"Why do people have red eyes in flash photographs?." HowStuffWorks - Learn How Everything Works!. 16 Nov. 2008 .
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