What is used to reduce red-eye?

Red-eye reduction is a feature found on many modern cameras. It simply attempts to constrict a person’s pupil so that not as much light can be reflected back from the retina. There are several methods of accomplishing this. One method is to have a smaller light that illuminates before the real flash; another method is to have a quick burst of five or six mini-flashes that cause the pupil to contract before the picture is taken.


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