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Is extreme Red Eye a sign of a physical problem?
Tip Provided by Dave
Question:
My grandson's pictures always have extreme red-eye that can't be repaired. I've tried and turned him into a white eyed zombie, but there's no way you can get the red out. In a group picture he's the only one with red-eye. My son thinks he heard someplace that extreme red-eye might be the sign of some physical problem and now he's all worried. I figured if anybody would know anything about that somebody on here would. Does anybody ever remember reading anything about that? Thanks
Very light blue or light blue-gray eyes will sometimes not photograph well Char. The colored iris of the eye tends to blend in with the white of the eye.
True "Red Eye" is the result of the flash entering directly into the person's pupil, reflecting off of the retina (which is rich with blood), and back out at the camera (like the pool ball example in Fig. 2 the other day). If one person's eye is irised wider open than other person's eye, the "red eye effect" will be more noticeable.
By the same token, if one person's eye is considerably farther open than another's, under the same lighting conditions, it could mean that person's retinal sensitivity (rhodopsin production) is less that the other's. You might want to mention it an ophthalmologist and see what he says.
Very briefly, the eye's rods secrete a substance called visual purple, or rhodopsin, which provides for black & white vision, especially in dim light or semidarkness. When light rays are focused on the rods, a chemical reaction takes place in them. The pigments are broken down to form a protein and a vitamin A compound. This process generates an electrical impulse that's sent to the brain and we call that sensation vision. If this change isn't balanced by the formation of new pigment, through the recombination of the protein and vitamin A compound, the sensitivity of the rods can be reduced.