Like the SB-800, the SB-900 includes a handy SU-4 mode. This allows the SB-900 to be optically triggered by seeing any other flash, even a non CLS flash. Using the SB-900 in SU-4 / Manual mode allows you to control the output just like any studio flash. However, unless my units are faulty Nikon seems to have forgotten the audio beep function to notify you when the SB-900 has completed the recycle and is ready to fire again. I always liked this on the SB-800 and it’s one more backwards step that I hope they will address in a future firmware update. Continue reading
To set the Nikon SB-900 to Master mode, press and hold the power button and rotate the switch to the ‘MASTER’ position. Continue reading
On 1 July 2008 Nikon announced the introduction of the SB-900, and so began the next step in lightweight portable, hot shoe mounted speedlights, bringing several important new features not previously available on any brand.