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When you see a person's
eye glowing in a picture, you are actually seeing
the light reflected off the back of their eye. Why
is it red? Because the retina is red. A person's
pupil is normally black because there is no light
inside the eye, and thus it is black. It would be
like cutting a small hole into the side of a
closed box. The hole would appear dark because it
is dark inside the box. However, suppose you would
put a piece of aluminum foil or a mirror inside
the box opposite the hole. If you would shine a
flashlight at the hole from the outside, the light
would bounce off the reflective surface and come
back out the hole, causing it to glow. This is
what is happening when you see people's eyes
glowing in pictures. The "Red-Eye"
effect spoils many otherwise perfect
photos. |
