Apple Aperture Digital Photography Fundamentals - Manual (Page 24)

24 Chapter 1 How Digital Cameras Capture Images
There are a few ways to minimize or eliminate red-eye in your pictures. Some cameras
provide a red-eye reduction feature that fires a preflash, forcing the irises in your
subject’s eyes to close before you take the picture. The main problem with this method
is that it often forces subjects to involuntarily close their eyes before the image is taken,
and it doesn’t always completely eliminate the red-eye effect.
A more effective method is to use an external flash via the camera’s hot-shoe mount or,
better yet, with an extension bracket. An external flash radically changes the angle of
the flash, preventing the lens from capturing the reflection of the blood in the back of
your subject’s eyes.
While you can also fix the red-eye effect using Aperture, there is no way to accurately
reproduce the original color of your subject’s eyes. Preventing the problem before it
occurs is the preferred solution.
Light enters the eye and
bounces straight back into
the camera, causing the
red-eye effect.
Built-in flash
External flash unit Light enters the eye at
different angles, diffusing
as it leaves the eye.