Mixing Speedlite 600EXii's and 580EXii's.
(Somewhere in Texas)
Speedlite 600 Vs 580 LCD Screens
"I have a ST-E3 Transmitter, two Speedlite 600EXii's and two Speedlite 580EXii's. Currently using the two 600's as radio slaves. Works fine. I'd also like to use the 580's in close proximity to the 600's. So, I would think that I could keep using the 600's fired (via radio signal) and use the 600's, in turn, to fire the 580's optically. But I don't find anything in literature and no menu options that indicate that the 600's can act as radio slaves and optical masters at the same time."
Thanks for your question about combining Canon 600EX II Speedlites with Canon 580EX II Speedlites. That's quite a question. I have both the Canon 600 and 580 flash units too.
Canon Speedlite 600EX II Vs. Speedlite 580EX II
For the benefit of other Canon Geek readers, one is built using light rays and one is built using radio waves to signal other flash units (as masters and slaves) in a lighting setup with multiple flashes.
I'm a simplicity geek (especially when it comes to lighting) and I've never attempted a lighting set-up with several of my Speedlites at the same time, so you should take my answer with a grain of salt. I would take the big step and update to all Speedlite 600s and the superior radio (instead of optical) communication between your speedlites.
Probably not the answer you're hoping for-I know it's a big investment. I made a similar decision when I was using Q-Flashes for shooting weddings a long time ago. I had 2 systems from the same company, but the jump in technology advances made the two flash systems incompatible. It was tough to update.
Let me know how you solve your dilemma,
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