Great product, all commands in the 580EX II flash are deported! zoom, exposure compensation (vital) Everything is accessible from my 600D ETTL flawless operation. The dream! It runs from the device the amount of light provided by the flash (exposure compensation) to ambient light, even if the flash is directed to the back wall to diffuse the light. This is not just a remote trigger a flash in manual. There, the ETTL flash operates according to the brightness seen by the camera. Incredible for that price you get to transmit all the information a flash. The menus are intuitive and logical, even those added by the YN 622 as the management of the ratio between two flashes. Just for curtain I have read the manual. Ideal for making beautiful pictures in high speed sync sunlight to simulate an American night
I have not tested autonomy but certainly more than the flash itself. AA size batteries or batteries like flash I recommend!
