Paul C. Buff, Inc. Technical Forum

I just purchased the Cybersync CST and the CSRB+. I was hoping to use these for a setup where I would have a 580EXII firing as a master in Manual mode, which would trigger a 430EXII optically in slave mode (also in Manual). However, when I try to trigger my 580EXII as a master in Manual mode, the trigger won't fire. If I have it in ETTL, or if I have it in Manual mode with the Master mode turned off, it works just fine. Is there a reason why the triggers won't work with my flash in Manual mode as a Master?

I believe the reason is E-TTL controls not only metered output (where "TTL" originated), but it also controls the wireless communications between two flash units. Since the CyberSync system breaks the TTL communications path, the 580 is not able to give a command the 430 can understand, as the 430 does not have a "dumb" slave eye like studio flashes or Nikon's SU4 mode.

I have never heard of anyone getting this set up to works on a Canon system.

The solutions would be to either use an additional CyberSync reciever (and and adapter like our SLFA http://www.paulcbuff.com/slfa.php) for the 430, or get a dumb slave eye that will fit to the foot of the 430.