I borrowed a new Canon 600EX-RT from a friend and I was just wondering if it has the "optical slave" like Nikon does(where you put it to SU-4 mode, and it "sync" with almost any camera that produce a flash). I looked at the instruction manual online, and the "optical slave" that Canon refer to requires a second flash… so is there a way that I can slave a 600EX "optically"?
Thanks.
>>> Does the new Canon 600EX-RT have the optical slave like Nikon?