It appears that the Canon EOS 5D Mark III (price & specs) has a problem with freezing after having captured a video clip up to a given time limit. The issue may be related to certain CF cards, independently of the card speed. Users report that the camera locked up and lost footage when it reached the 30 minutes limit for clips. Users started a petition to move Canon to release a fix. The letter says:
You have probably heard of many customers globally having problems with Canon 5Dmk3 camera freeze and lost files, both video and stills. If not, this is just one of quite a few forums discussing this for your reference – http://www.canonrumors.com/forum/index.php?topic=8732.0
We need to draw your attention to us needing you to get it fixed ASAP.
As simple as that – admit it exists and find a solution, please.
We can’t afford losing our files any longer and using the gear that have a problem that is intermittent.
Canon’s answer to one of the users (source: nofilmschool):
We are not aware that there is an issue with these Sandisk cards within the camera. If you suspect it to be the cards, I would recommend trying a different brand and or size to see if the issues persist. We are not aware in advance when new firmware and or changes are coming to the camera. Anything like this would be announced on the Canon EOS web site. I would say that if another card causes the same issue you would want to send the camera in for service. Currently we are not able to recommend one specific brand of cards over another. We apologize for any inconvenience that this may cause you at this time.
It seems to be an intermittent problem, difficult to replicate. The discussion started in this forum.
Have you experienced the issue, is your EOS 5D Mark III freezing?