Redeye

Red-eye is caused by light from the flash reflecting off the blood vessels in the retina of the eye. Several factors can contribute to red-eye: low light situations where the eye's pupil is wide open, the color of someone's eyes (light complected people are more susceptible), someone's age (iris reaction time is much slower in young children), the direction of someone's gaze (people who look directly into the lens are more susceptible), and other factors. This phenomenon has been documented extensively in photographic journals, papers, and other sources.

In recent years, with the development of ever more powerful flashes and greater zooming capabilities of cameras, red-eye has become more of an issue with photographers. If you use any camera with a built-in flash, your pictures are susceptible to red-eye. Tiny cameras are even further susceptible to red-eye because the flash is even closer to the lens than in other cameras. The PENTAX red-eye reduction system therefore uses a pre-flash to close down the pupil of your subjects' eyes thereby reducing the amount of light that enters the eyeball when a flash picture is taken. While you may not eliminate red-eye entirely in these circumstances, you can take some additional measures to help reduce it further:

- Increase existing light to help reduce pupil size (this is the best possible thing you can do).

- Get closer to your subject (red-eye reduction has an effective range of 5-10 feet.

- Use a wider angle (less than 50 mm).

- Having your subjects look slightly away from the lens may help to redirect reflected light from the flash.

- Digital pictures can be corrected in an image editing program. For film pictures, consider the purchase of a red-eye pen to correct pictures after printing.