Nikon
SB-900
AF Speedlight Flash
The SB-900 from Nikon is a powerful AF Speedlight featuring a guide number of 111.5' at ISO 100 and an automated zoom head to cover a wide 17mm to 200mm focal length range. Tilt the flash down to -7° or up to 90°, with the ability to rotate the flash head horizontally 180° to the left and right, and select from three light distribution patterns: Standard, Centre-weighted, and Even. It will also automatically detect if it is connected to a DX or FX format camera, and adjust itself accordingly.
The SB-900 can work as a stand-alone flash, or as part of a wireless group, either in Commander mode or as a slave. Its i-TTL system supports Advanced Wireless Lighting and versatile functions for up to four groups of Speedlights, with 3 remote i-TTL Speedlight groups controlled through the master SB-900. Individual flash mode settings ([TTL], [AA], [A] and [M]) are available for each of the four groups (including master controller) for total lighting control based on the brightness of the subject and not simply on general output ratios for each group.