Canon Releases R5 Firmware Update To Improve Overheating... But Does It?

Not by much. 

Canon has released firmware version 1.10 for the EOS R5 that is said to address some of the overheating issues that have surfaced with the full-frame mirrorless camera. Below is what Canon says the update improves: 

Firmware Version 1.1.0

  • Useful messaging is now displayed when [HDMI display: Camera+External monitor] and [Overheat control: on] settings are enabled
  • When using certain RF lenses for movie shooting, the in-lens image stabilization mechanism has been improved
  • Fixes a phenomenon in which the "Slow Synchro" setting screen is not accurately displayed when the language is set to English.
  • Fixes a typo displayed on the communication setting screen when the language is set to Korean.
  • Connectivity during FTP transmission has been improved
  • Fixes a phenomenon, in which the card access time may take longer when using certain CFexpress cards
  • Temperature detection and shooting time control in video shooting have been improved. In addition, the total shooting time when the short-time recording and power-on/off are performed repeatedly at room temperature is improved
  • The phenomenon in which the movie recording time available is not correctly displayed when the Date/Time/Zone is not set has been corrected

What catches the eye is the second to last bullet point. It suggests that shooting time, as well as recovery time, has improved. This has been the sore point with the R5 thus far. So much so that users have found workarounds to extend the recording time with transparent tape and a toothpick or using an external recorder in 4K HQ mode

No Film School has reached out to Canon for comment on a variety of topics, including the overheating issues. If Canon responds, we'll share them in an article. 

According to Gordon Laing, he's learned that the R5 has 3 temperature monitors: 2 that are in close proximity to the sensor and a 3rd that measures external temperature near the ports. Using readings from all 3 and a timer, the camera decides exactly how long it can record. The latest firmware is supposed to improve those measurements and times. 

It's important to note that the firmware doesn't change the temperature at which the R5 starts to overheat, nor does it change what Canon considers optimal temperature, that's still around 73°F (23°C). But the new firmware is supposed to provide more accurate feedback from the sensors, and thus, possibly extend the record time and shorten the recovery period. Laing suggests that the outside temperature will play a more active role in allowing the R5 to recover faster. 

No Film School downloaded version 1.1.0 and did a quick test of our own. In our initial overheating tests, the R5 recorded internal 8K RAW from a cold start indoors for about 19 minutes before shutting down and took about 20 minutes to recover for the first recording. 

For this test, since we had the R5 on to update the firmware to 1.1.0, the camera's internal temperature rose. This meant the camera was not at a cold start and displayed 15 minutes of record time in 8K DCI RAW and 8K UHD ALL-I/IPB modes. 4K HQ modes dropped to 17 minutes. However, standard 4K DCI/UHD at 29.97 and below in IPB displayed a 29:59 record time. 

We recorded a single clip internally using 8K IPB at 29.97fps to an SD card. Canon Log was turned on with a neutral color matrix using a Rec.709 color space. While the latter specs generally don't affect record time, at least you know the settings. The camera was placed on a tripod and left to continuously record at room temperature without any external fans or cooling methods. 

The camera started to flash its overheat warning at the 12-minute mark and then shut down (Overheated! Shutting down) after recording 17 minutes and 19 seconds. The camera was turned off and the SD card was removed for 10 minutes. After turning the camera back on, the R5 displayed 5 minutes of record time. The camera was put in record mode again.

This time the overheat warning light came on after 2 minutes and 32 seconds. The camera shut down after 5 minutes 55 seconds of continuous recording. Like in our previous tests, when turning the camera back on and switching to 4K HQ mode or 4K 120p, those modes could not record. 4K DCI/UHD at 29.97fps (and lower) IPB displayed a 29:59 record time. 


After a full 12 hours of cool down time, the firmware was tested in 4K HQ mode from a cold start. The starting time displayed 25 minutes. Canon Log was turned on with a neutral color matrix at Rec.709. In-body image stabilization (IBIS) was turned to On, which reduces the full-width of by 90%. Lens autofocus was on and the camera was operated handheld to force the IBIS and autofocus to continuously work. 

The overheat warning light came on at 26 minutes 32 seconds and the camera stopped recording after reaching 29:59 because of max recording times. It was put back in record mode and then shut down after 33 minutes. The camera was turned off, and after cooling for 10 minutes, it displayed 5 minutes of record time. The second continuous recording shutdown after 10 minutes 16 seconds. 

When comparing that to our initial test using firmware 1.0, there's about an additional 5 minutes of record time and a reduction of about 3 minutes in cooling time. 

While there may be a slight improvement, it's not a very significant one. More testing will be needed, especially outdoors. What will be interesting to find out is if this firmware update helps record additional shorter takes. It's also not known if the firmware eliminates any of the aforementioned workarounds that extend the record time. It's doubtful but we'll have to wait and see. Does anyone have some Scotch tape? 

You can find out more and download version 1.1.0 here.      

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Your Comment


Well, it seems fair to say that Canon has done basically nothing substantial to address R5's 'overheating' issues with this firmware update. They continue to play dead fox, and although it has been proven that the 'overheating' is actually non-existent, and is strictly a software-related limitation, they have decided to stick to their crooked guns and weather the PR storm that is already raging. Too bad! I have lost my faith in Canon, and will be looking elsewhere.

August 26, 2020 at 11:49PM

Pavel Tsvetkov

You just said everything I wanted. I just can't imagine how the meeting went down when they decided to artificially cripple the camera and whose idea it was to go the fake overheating route.

August 27, 2020 at 4:41AM

Tomaz Kovacic
Self taught: Director, VFX artist, Editor,...

Obdurate pride and hubris.
They offer a limp firmware update and think all will be well.
There needs to be a changing of the guard at Canon - soon.

August 27, 2020 at 7:10AM


I have been using the camera in the real world for about 3 weeks now and have not had any overheating issues yet. I am not saying the issues are made up, but I have not experienced them yet..

August 27, 2020 at 10:13AM

Walter Wallace

First they offer full transparency as to the overheating possibilities with a chart and everything, second they update the firmware to increase the times listed on the charts. It seems Canon is doing right by their customers in letting them know the cameras limitations before they got it into the hands of their customers.

Right above my comment as I type this is another NoFilmSchool article about "Sony Improves Overheating on a7R II & a7S II with New Firmware Updates"

It seems full frame mirrorless cameras, no matter the brand, have these issues. Sony is more than four cameras deep (Canon has the R, RP, R5, R6) into the mirrorless market and still having these issues. Maybe we shouldn't be ripping batteries out of cameras, putting cameras into the fridge, and making weird memes about other photographers.

Instead let's just not purchase these new cameras with these flaws if the flaws aren't something we can work around.

August 27, 2020 at 11:43AM

Nick Straub

I would suggest that a 25% increase in the 8k raw recording times by tweaking the firmware is a pretty good increase. It might not be the doubling or tripling of the time limits that you are looking for but it is a major improvement a month after release... and it was released with full disclosure up front of its limitations. People could not buy the camera without knowing the limitations and there still is a big backlog on order.
Standard 4K is still unlimited even when 4KHQ,4k/120 and 8K modes are not available. Not sure why this is not mentioned when talking about overheating.
Surely external recorders are cheaper than the large CFe cards that would be needed for long recording times.
A more interesting point is their press release about the next firmware version with lower bitrates, clog3 and HD/120p. Hopefully, 8k raw and 4k/120 could be recorded externally and without the heat generation of internal cards, it could mean longer record times again.

August 27, 2020 at 8:13PM