Nikon D100 - Manual (Page 109)

Taking Photographs—Flash Photography
Using Built-in and Optional Speedlights
97
Red-Eye Reduction
Depending on the lens used and the position of your subject, the AF-assist illuminator
(red-eye reduction lamp) may not be visible to your subject, with the result that red-eye
reduction may not have the desired effect.
Studio Flash Systems
Rear-curtain sync can not be used with studio flash systems, as the correct synchroniza-
tion can not be obtained.
Flash Sync Modes for Optional Speedlights
Front- and rear-curtain sync modes for SB-series 26, 25, and 24 Speedlights is set using
the sync mode selector on the optional Speedlight. If red-eye reduction or slow-sync
with red-eye reduction is selected with an SB-series 80DX, 28DX, 28, 27, or 26 Speed-
light attached, the Speedlight red-eye reduction lamp will be used.