brighter modeling lights?
I'm using the 800 for studio still life too. The only thing that I've found is like Ellis says, put the modeling light all the way up (not on tracking) and open the lens up wide. Grrr. Sometimes I pull out my mini-Mag lite LED flashlight and zap that on the focus point. Then, if I get preoccupied with being ticked off, I forget to stop back down. I hope that rumored firmware fix is real.