Paul C. Buff, Inc. Technical Forum

I use 4 Alien Bees flash units with the wireless CyberSync transmitter and receiver system. I works perfectly in my home studio but last week we were shooting in a big industrial building which was well-lit by huge daylight lamps on the ceiling, and we had trouble making the flash units "seeing" each other. Only the flash which had the receiver was firing (but all units fired correctly with the test button). The channel was selected correctly, and the battery was new. We had to increase the power of the master flash unit (the one with the receiver) a lot, and then the other units started working.

Is it a "normal" situation? Did we understand right that too much of ambient light prevented the units from "seeing" the master flash firing?
Is there any fix for that? Increasing the power of the master unit fixed the problem but did not allow us to have the desired lightning set-up.

Thank you!!

Anna

This sounds pretty typical when attempting to use optical slaves in larger, open spaces. The slave sensor depends on seeing the direct or reflected flash from the master, and in small venues, indoors, works well.

I doubt it was the overhead lighting alone that caused you trouble, as when you increased power you managed to get them to trigger. Sometimes outdoors, in direct sun, the slave eye just wont trigger at all.

So, you know the solution already--add a receiver to each strobe. There are additional benefits to this: you have "spare" receivers on hand for any time you are using less lights, or for when you are in a situation where the slave can be used on one light if needed.

Also, if you are ever shooting in a place where others are firing speed lights, their strobes, etc. you won't have your lights firing every time they do :-)

Thanks a lot for the answer! :)