Red-eye is the term used to describe the reddened pupils of a subject’s eyes that sometimes occurs when photographing people or pets with an electronic flash. This effect often occurs when the pupil of the eye is dilated, usually in a low-light environment. The red color appears as a result of the light from the flash striking the rear portion of the eye and illuminating the blood vessels. Red-eye can often be avoided by placing the flash farther than 6″ from the camera lens.
The reason red-eye is most common with compact digital cameras is because the flashtube is often adjacent to the lens, thereby causing light to enter a subject’s pupil head-on. A common pre-capture cure for red-eye is to bounce the flash onto an adjacent wall or ceiling, which softens the light and eliminates any red-eye effects.« Back to Glossary Index