So this past Saturday night I covered a small movie premier which consisted of a couple of sit down interviews. I was shooting on my 5D MKIII and went the whole night without any problems, except for the very last interview at the end of the night. About 2 minutes into the interview the camera just shut off. My first thought was, "Did it overheat?", but it had been off for about 10 minutes prior to this interview.

So I turned it back on and started shooting again. A few minutes later it turned off again. I decided to pull out the battery (which was a fresh battery I had just put in about halfway through the previous interview.) and I put in another one. After that, I didn't have any problem. I am trying to figure out if that was a bad battery (it did show to have a full charge, and it was one of my generic batteries) or could it have been something funky going on in the camera and pulling the battery out let it reset?

I have not shot with that battery again, I separated it from the rest in case it was bad. Anyone run into an issue like this?

It's overwhelmingly more likely that it's a bad non-Canon battery rather than a camera fault.

I was thinking it was probably the battery. However, the 5D MKIII is still new and I have already found a couple of quirks with it, so you just never know. Having been a Software QA tester before, you never know what combinations of actions can cause an issue.

'Quirks' is right. Besides the issue with the manual lens and live view mode issue mentioned in another post today, I've had a few other experiences.

The other day I was out shooting and to get live view display back (before I learnt of the pressing a function button trick), I took a photo in live view mode. The LCD displayed the image as normal and then it froze with the image right there on the screen. I couldn't do anything. Even when I switched the camera physically OFF, the image remained on the screen, the 'writing to card' red tally lamp stayed illuminated and top LCD display stayed on too. It was the wierdest thing - Even my 5D2 never did that.

Eventually, after a few minutes, I took out the battery. That reset the camera and it resumed normal operation after.

I thought about returning it, but I can't reproduce the fault.