I own a Canon EOS 600D (Rebel T3i). I bought a second hand Speedlite 500EX. It works well when I put it on top of my camera.
However, I cannot get it to function as wireless slave. I've made sure the camera and the Speedlight operate on the same channel (I tried all four channels), that the Speedlite is set to slave and that I selected "Easywireless" as the function for the internal flash (so it operates as a remote master).
But no matter what I try, the Speedlite refuses to flash wirelessly. The only thing I can think of that might be wrong is that the camera uses E-TTL II and the Speedlite E-TTL. But as far as I can see, these should be compatible.
Anyone got an idea of what's going wrong? Thanks!