Olympus iS-3 DLX Instructions Manual page 28

Approximately 20 pre-flashes are emitted before the main flash fires,
significantly reducing the phenomenon of "red-eye" (when a subject's eyes
appear red). This mode is the same as Auto Flash except for the pre-flashes.
Flip up the flash, and
select the Auto-S mode.
Notes:
The pre-flashes are not emitted in the Sports mode.
After pressing the shutter release button, hold the camera securely until the shutter has been released.
To cancel the Auto-S mode, select another mode following the procedure on page 23.
28
Red-Eye Reducing Flash
AUTO-S
Press the shutter release
button.