draderusa wrote in post #17054285
This is quite a surprise because the RF603ii does not have enough pins on top for full ETTL communication. It only has enough contacts for the wake up feature for a sleeping flash. I do not have a YN-565 so I can not confirm its behavior but I just placed a 600EX-RT on top of a 603ii and tried to access the external flash function menu on the camera. As expected, the camera will not open the menu and states: "an incompatible flash is attached". When I ignore the camera menu and set the flash itself to ETTL I get a full dump. Yongnuo says this is NOT full ETTL passthrough and this is confirmed by the oracle of all things flash, Elv, in his www.flashhavoc.com
review of the 603. I am sincerely pleased that you somehow have this working on your particular set of equipment I don't want others to be disappointed when it doesn't work for them. The fact that yours works is just this side of a miracle.
I know it says it shouldn't be possible. Dunno why mine works. But if it didn't work, how is it possible that it alters power level appropriately in each room at different ambient light levels? I just don't know. But it is working. Maybe it's just not working perfectly? But so far, the images don't seem to show a problem.
Again, dunno why it works, it just seems to be working fine. It's weird.
And not trying to trick someone into getting them thinking it's 100% legit for them. I don't know why it's working for me (XSi, 650D, EOS-M and 5D for reference).