A number of Canon 1D X Mark III owners have reported issues with Canon’s flagship DSLR, wherein the camera appears to lock up and fall asleep while shooting in continuous mode.

First reported nearly three weeks ago in the DPReview forums, users have noticed their 1D X Mark III cameras seizing up after a few shots, making the camera unusable for a few seconds until it appears to reset. DPReview reader Hamilton Pytluk made what we believe to be the first mention of the issue when he had the following to say (emphasis his) in the Canon EOS-1D forums:

"My only gripe so far [with the 1D X Mark III] has been what I believe to be a buffer “issue” when shooting through the OVF, which seemingly puts the camera to sleep after taking a series of shots (as few as 5 in my usage) and de-pressing the shutter (if you keep it half-pressed, it’ll stay “awake”). Everything shuts down — I can’t even open the menu — until the write (red) light stops flickering."

DPReview forum member PrestoPhotographer responded to Pytluk’s post confirming they too were affected by this issue:

‘I have the same issue with the viewfinder ‘sleeping’. Incredibly frustrating when shooting soccer or any fast-moving sport. I’m sending mine back as it’s currently not usable for me. I’ve noticed the card access light going off randomly amongst some other bizarre things as well. I’m set up for an eventual exchange but no clue when they’ll get more stock.’

Pytluk responded with the following YouTube video, showing exactly what both users described: after ten shots in continuous mode, the digital markings on the optical viewfinder (OVF) went blank and shut off until the camera caught back up, at which point the shutter could be released again.

Follow-up posts in the thread confirmed this issue occurred regardless of whether or not a memory card was inside the camera.

We experienced a similar issue with a pre-production camera earlier this year, but have not replicated the problem with two production samples of the EOS-1D X Mark III currently undergoing testing at DPReview. We have contacted Canon for comment and will update this article if we receive a response. If you’ve noticed this issue on your 1D X Mark III unit, leave us a message in the comments below.