Using SB400 and SB600
Can I fire both simultaneously from my D90?
If so, how do I set it up?
The manual says that the SB400 is CLS-compatible, but I don't know how to control it, unless I mount on the camera, which disables Commander mode.
I found this thread, which seems to say they can't be operated together, and that the Sb400 cannot be fired remotely: