I know that this is belated for me to address, but I still haven't quite figured out how to optimally use my SB-600. When I use my D300, I usually just have to guess what intensity goes with what aperture and what ISO setting. This can waste seconds and shots, and almost always requires retooling in photoshop, etc. What am I missing? I'm going to the Obama rally tomorrow in Chicago and I want to make sure I get everything right. Is there a way to make it so the flash knows what ISO/f/shutter gives it the optimal intensity?