New twist in the R5 Overheat


CR Pro
Jul 16, 2020
So... just want to be clear about a few things first.

I love the R5. I am a stills shooter. I film very little video. And I hate misinformation and overhype/overdramatic YT videos.

That being said I keep an eye on things... as I have a genuine interest in hardware in general... and I'll be honest, I really want Canon to succeed here because I believe their glass is awesome.

So story goes like this so far...

Canon issues press statement glorifying the video capabilities.
Everyone: Thinks it cool

Canon publishes the specs that go into the heat limitations
Me: Ok
YT Personalities: OMG the sky is falling, lets report this to death.
General 1: Yup, it does what's stated
General 2: Hey that's not what they told us in the press release... they lied.

People then do silly things to get it to overheat.
Me: thinks it's most useless dribble. Just because they are only confirming the run times of what specs state.

Some people go into further testing to back up claims that are not really in the overheat specs. These topics are what I found interesting.
-Just using the camera takes away from the video. Ok this was expected, but not to the extent.
-Cooling the camera doesn't seem to help recovery times.
-Ambient temperature doesn't seem to effect overheat times.
-Recovery times are more than expected.
-Pulling the memory card and recording with the Atomos greatly increases record time (those CF Express Type B cards are hot you know).
-The teardown of the unit... essentially proving the magnesium body isn't helping cooling since the heat generating chips are not heat-sunk against anything (actually they are sandwiched between boards)... why Canon, why.
-Seeing a comprehensive temperature readings.
-Pulling the clock/non-volatile memory battery instantly makes the overheat recover.

The last one really had me thinking and is the plot twist IMO (but the normal person isn't going to tear down their camera to try this). Then I just found this gem today involving basically the battery trick that anyone can do w/o opening their camera up.

The TLDR version is the overheat info gets written to memory that the battery maintains when the battery door is opened. So if you remove the battery when the camera thinks the door is closed it doesn't have a chance to write to the memory that the battery maintains. Anyway this guy does a good job of explaining it and deserves the credit...

The battery trick is what really has me interested, as it proves it is the software, not the thermal temps that really drive the recovery time. So a firmware update could be a real solution to this.

So a few theories on this...
-The engineers went overboard on protection due to uncertainties.
-This part of the firmware never got finalized for production due to covid-19/rushed delivery/insert other excuse, and better the camera not overheat (for real) and cause damage till they could sort it out.
-They don't have good or enough temp sensors in the camera, and have to rely on worst case computations of recovery.
-They thought it was good enough.
-It really is overheating
-Canon did it to cripple the camera.
-Or all, some, or none of those...

Now, I'm not about to do the battery door trick (I'll leave that to others to take the risks), however if it is found that the trick does not do long term damage, it would be very helpful news.

However I believe this information is useful to get out to the masses as it might actually pressure Canon to do something (or at least provide a reasonable explanation). As it is now, this is something they are limiting through programming, not direct sensor reading.

If it truly is hitting thermal limits, I can accept that. However, there is some truly funny business going on that shouldn't be IMO. If the thermal limits say operation is limited by camera temp, and by doing the battery trick it resets the data... but temperatures don't change, why isn't that kicking off the limit again?

Just want to sum this up. I'm still happy w/ the R5. However, I'll take a free increase in recording time and decrease in recovery time as long as it doesn't degrade the camera over time. Why would anybody pass that up.
  • Like
Reactions: 2 users


Sep 13, 2011
I don't think anyone has a problem with accepting the thing gets hot. Two hours before you can record again or having reduced time when you've only been shooting stills is upsetting many though. Even though I don't do any video at all that kind of limitation seems a bit odd to have.

On the flip-side, it says this camera is amped. At least compared to the 5DSr.
Last edited:
Upvote 0