Every time you take a picture, regardless of the lighting conditions. Use when the subject is in shadow or is "backlit" (when the light is behind the subject). In low light, hold the camera steady or use a tripod.
Red Eye
Your camera can correct red-eye using 2 methods. To choose a setting in the Setup menu ().
Preflash
A preflash fires, shrinking the eye pupil, before the picture is taken.
Digital Correction
The camera digitally corrects red-eye after a picture is taken.
NOTE:
When using digital correction, image processing takes longer than when using preflash.