Author Topic: Extreme battery drain on 5D Mark III even after uninstalling ML  (Read 83 times)


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After trying out magic lantern on my 5d mark iii version 1.2.3 and properly uninstalling it, i noticed my battery life was terrible (i am using a 6 AA battery grip genuine canon) and i was getting less than 15 minutes with brand new alkaline aa batteries. No matter how many times i got new ones for it was now saying they were low. I used a battery tester and they were like new still full. And occasionally even though i fully uninstalled ml, my camera after believing it was too low battery it would not turn on and show the flashing battery icon. Has Magic Lantern damaged my camera? I really need help as this camera needs to be used for a shoot on Wednesday and it currently can not be used for more than 15 minutes vs originally 2 hours or so with fresh batteries, even though magic latern is supposedly uninstalled. I used the method mentioned in the F.A.Q for uninstalling.


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Please provide the battery drain rate in some measurable units ("I used a battery tester" doesn't count).

With a (reasonably good) Canon battery, Canon firmware reports the percentage
- set the LCD backlight level to maximum (Canon menu)
- open Canon menu, select Battery info and write down the percentage and the time (wall clock)
- leave the camera in Canon menu for a while (say 10 minutes) and write down the new percentage and the time
- the camera doesn't update this percentage while you are on this screen; you need to go back and forth to get a new reading
- repeat with LCD backlight set to minimum
- repeat for LiveView (keep the camera in LiveView while waiting between the two readings)

With ML, the battery drain rate is shown in the Debug menu; just leave the camera for some minutes under the tested scenario before reading.

If you can modify an external power adapter, use an ammeter and write down the current while the camera is (1) in Canon menu, (2) in LiveView and (3) with the portable display test.

If you (or anyone else) can get the above figures (or only some of them) under the same conditions from a second camera (ideally same model, or any other model that uses LP-E6), that would be even better.

Also, please provide your usage scenario -- what you were doing during these 15 minutes, and in what camera mode? (in particular, with or without LiveView?)