Paul C. Buff, Inc. Technical Forum

How can I sync the Einstein™ E640 Flash Unit with new Canon 600EX-RT Speedlite Flash with the radio wave communication? Thank you.

The RT radio has no way to directly communicate to the Einstein, nor is there a receiver module for the RT system to connect to other units.

The only two options would be to use the optical slave function of the E640, however, this would require any preflashes to be turned off on the speedlite. I am not sure if this is possible, though I see no reason for it to not be.

The other option would be to run two remote systems in parallel. One for the RT speedlite(s), and one (i.e. CyberSyncs) for the E640. Depending on your camera, this may be relatively simple, or it may involve some adapters.

Thank you so much!