http://www.nikonchat.com/remote-nikon-d90/
Remotely adjust the power of the SB600 flash?
OK, I admit, I'm too lazy to read the manual that came with my flash … When I'm using Nikon SB600 my distance, and I decided to change the flash output from 0.0 to, say -0.7, this is transmitted remotely the flash of my camera (Nikon D90) to my remote flash unit? You get a price for their service here. Yahoo Answers gives you two points.
SB600 will have to set for remote operation. That is an uncle to do and have to follow the footsteps of his hand. Then you have to set the D90 to control the remote flash. That's in your camera manual, I have not. Look Commander Mode. For some reason my Adobe reader is not cooperating right now or you would say the exact name of the menu.
TR-M Timer Remote Control for Nikon D90
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