Surprised to see 3 out of 4 negative reviews, I have used one of these flashes on 3 different Canon DSLRs for over a year and have had no problems, it has always worked as it should and the charge time is Ni -Mh Depending on the state of charge, batteries vary from a few seconds to maybe 60, this is normal. The front/back curtain and E-TTL mode settings are available in the menus of every camera I've used it with. to be fixed on the hot shoe to keep a good contact, so it has a locking ringβ¦