I can now record 8K video on my Canon EOS R5 with no recovery period or lockout until the battery dies.
I filmed the proof and it’s a clear indication that any overheating controversy is the result of an artificially restrictive timer in firmware, rather than any real thermal buildup inside the camera at the end of 20 minutes of 8K recording, monitored by a temperature sensor.
We have been sold a lie.
I pointed my Sony A7R IV at the Canon EOS R5 as it recorded 8K for 51 minutes in three blocks of approximately 17 minutes each.
So the video you see above is completely uncut, one shot.
The only editing is a speed ramp to fast forward through the 17 minute chunks of 8K recording.
My technique to get the EOS R5 to do this is based on Horshack’s idea about the way the camera saves settings to non-volatile RAM at the end of a clip or at an orderly shutdown. Lodging a small screw in the battery door sensor, along with the battery pull and card swap makes the camera forget the cripple timer.
Here’s what I did during the 50 minutes 8K test:
- 00:00 – Power on the EOS R5 normal from cold
- 01:00 – Remove battery card door, camera powers down but power switch remains in “on” position
- 01:30 – Insert small screw in the battery door sensor as pictured below. Camera turns back on.
- 02:00 – Set video mode to DCI 8K resolution (IPB codec) to SD card.
- 02:10 – Hit record
- 17:00 – Roll to approximately 17 minutes (“overheat” warning icon will be flashing)
- 17:05 – At this point pull battery during recording
- 17:15 – With battery disconnected remove SD card and put freshly formatted SD card in the slot instead
- 17:20 – Push battery back in and power will return, overheat warning is gone and timer is reset
- 35:00 – Record for another 17 minutes!
- 50:00 – End of test
I could go until the battery died, basically.
The camera never got hot to the touch, cooler than my MacBook Pro the whole time.
Canon remain silent
I have reached out to my friend Michael Bravin at Canon in Burbank. After initially saying that the camera was on the set of Avatar 2 running with no problems(!) and promising to find somebody from the stills department to help answer my questions, Michael unfortunately went quiet and a number of follow-up messages have been ignored altogether. Which is a bit sad.
I also reached out to Dawn Vincent at Canon UK. After initially providing me with an existing PR statement about “overheating times” that contact has gone quiet too.
So something is very odd, and Canon are basically mute.
What happens next is anybody’s guess.
But that is absolutely gin clear is they owe their customers an apology and have a brand to rebuild.
Here we have an incredibly exciting 8K camera that needs fixing. I will not stop until Canon come clean and unlock the full potential of this camera in video mode.
We pay the money. We decide what is appropriate behaviour from Canon.
