Canon EOS R5 records 4 hours of 4KHQ 30p to an external recorder, with a couple of simple tweaks

tomislavmoze

EOS M50
Aug 6, 2020
29
42
So I've done another test, I took my sandisk CF-express 256gb card filled it full capacity and done a transfer of all the files to my MacBook pro which made it really hot to the tuch also reduced the speed of the transfer after I tried to put something back to it. The most interesting thing was the fact that I could not use any HQ modes on my R5 that was siting since last night on my desk in a shaded room. It seams that definitely the problem with overheating comes from the cf-express card and the communication of the camera with it.
20 minutes after the camera still can't shoot any HQ content, so it seams the problem lies in the card and its heat control that somehow blocks the camera, unfortunatly I dont have two cards to play a bit more with it.

This feels like the web's collective effort to figure this out, just like when Everybody in the world was searching for MH370.
Well The problem is canon gives certain number of cameras to their ambassadors, and maybe the number of those units is not enough to colect all the data, now with more units out in real life scenarios there will be more data about the camera and how it works.
 

anth455

I'm New Here
Jul 16, 2020
12
20
20 minutes after the camera still can't shoot any HQ content, so it seams the problem lies in the card and its heat control that somehow blocks the camera, unfortunatly I dont have two cards to play a bit more with it.


Well The problem is canon gives certain number of cameras to their ambassadors, and maybe the number of those units is not enough to colect all the data, now with more units out in real life scenarios there will be more data about the camera and how it works.

Wow I had assumed it was increasing the ambient temperature in the the camera while writing.
But this may indicate it can some how know the temperature of the card!
So maybe its not the down sampling of 8k to 4k that is causing high temperature. But that is the only difference from hq and non hq. The bit rate is the same.
 

tomislavmoze

EOS M50
Aug 6, 2020
29
42
Wow I had assumed it was increasing the ambient temperature in the the camera while writing.
But this may indicate it can some how know the temperature of the card!
So maybe its not the down sampling of 8k to 4k that is causing high temperature. But that is the only difference from hq and non hq. The bit rate is the same.
I tired to replicate the same scenario, and the second test did not lock me out. I guess this all to firmware 1.0. They have a lot of things to clean and polish.
 

Whowe

EOS 90D
Mar 4, 2020
121
128
Actually, I believe physics works that way. If a thing (a component inside a camera body) can cool down nearly completely within 2h, then it must have a certain thermal conductivity towards a heatsink (environment). With constant heat input, there is just no way it overheats only after 4 hours. If heat buildup takes that long, cooldown will take even longer. So, if the camera overheats after 4 hours, it will not be completely cool after 4 hours either. Still, recording times are fully recovered after only 2h, apparently.
You are right that it all has to do with thermal conductivity. But just for a second, think about a camera body with a high thermal conductivity. It can remove the heat as fast as it is generated inside the camera and the camera never overheats. This unit will also cool down quickly when the heat source is removed because it can transfer the heat quickly. (time to over heat >> cool down time)

A body with a little less thermal conductivity, but still a high rate of heat transfer, will still remove heat quickly and take a long time to over heat, but will also cool down quickly. (time to over heat > cool down time)

A body with poor thermal conductivity (i.e. low heat transfer rate), will heat up quickly since it can not remove the heat. It will also take longer to cool down, again because of the low thermal conductivity (i.e. low heat transfer rate). (time to over heat < cool down time)

So high heat transfer out of the body tends to result in a camera taking a long time (if ever) to overheat, but will also help cool down quicker. On the other hand, poor heat transfer would likely result in quicker overheating and longer cool down times.
 
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Pape

EOS RP
Dec 31, 2018
603
364
I found this review https://ihitthebutton.com/canon-eos-r-vs-eos-r5/

It compares the hq vs non hq. Its the last two images. Its saying its a 200% crop! Who views a video at 200% ?
So I saved the first file and cropped out the non hq then viewed them at 50% so that should now be 100%?
They are a bit different but I think if this was a moving video you may find it hard to notice. So then I sharpened the non hq and it looks nearly the same.

I have no idea why removing the card allows more recording. Only thing I can think of its firmware bug or something in the camera generates more heat with a card in the slot? The actual writing to the card is probably not the problem because hq and non hq are the same bitrate 470Mbps. If it is a real heat problem then its probably because its reading a lot more pixels in the encoding for the over sampled version.

I assume line skipping reads half of the pixels from the sensor. Also encoding half of the pixels. Oversampling has to read all of the pixels on the sensor then down sample it. I think doing this may make it read the values from its internal buffer multiple times for each new pixel in the down sampled version. So reading all of the pixels from the sensor probably generates heat and processing twice as many pixels also.

The only other thing I can think of is it can output uncompressed down sampled 4k while staying in the heat limit. But doing that and encoding it and writing it to the card goes over the limit. So by not encoding it and writing it to the card you are saving a lot of processing power/heat. We may not see a solution for internal recording if its really at its limits unless they either make the code more efficient or add more heat sink to the processor. I don't see this working for the sensor but that appears to not be a problem because it is ok with external recording. It looks like the card may play a smaller part because ipb vs all-i does not change the recording times but all-i would stress the card a lot more. But it is possible that the heat from the card is increasing the internal temperature to the point that it can't do over sampling and encoding not going over the limit. So its not that it can't handle writing hq vs non hq to the card just that it makes the internal temperature too high to do it for a long time with over sampling.

Not using all of the pixels (line skipping) is probably what causes the small amount of softness. Its a while since I have looked at any image processing code but I do work as a software developer. So this is just my logic of what could be going on. Not sure if down sampling from 8k to 4k is that expensive on the hardware they use on this type of camera. But once it is down sampled it is now the same as the non hq version in terms of processing to encode it!
Line skipping is more challenging for optic i believe ,softness may be from soft optic too? Nearly all RF lenses are soft with 45mpix sensor.
Every RF lense makes max sharp with downsampled Hq4k
 
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adigoks

EOS 750D
Jul 12, 2020
58
66
card.jpg


after this so much drama. people start to get the idea why overheating happens while canon already wrote down the cause of problem in their manual . :ROFLMAO:
 
I tired to replicate the same scenario, and the second test did not lock me out. I guess this all to firmware 1.0. They have a lot of things to clean and polish.
Great testing, thanks - certainly seems to be highlighting where the focus should be.

Would it be fair therefore to reverse the test. I think I have read that blowing cold air into the card socket makes no difference. Could you record 8k and see if you can get a quicker recovery time by just cooling the cfexpress card once removed from the camera (a lot cheaper than you buying another card)?

As the heated cfexpress card showed overheating then one might deduce the controller for the cfexpress is ok - as you say the camera was unused. So if you can cool the card, will that extend the times or will we find that even though the cfexpress card is clearly generating heat and when too hot prevents it being used, there are other components generating heat that the r5 can’t dissipate quick enough when recording 8k? Would love to be able to help you test, but mine is still stuck in pre-order phase...

Great work again, thanks.
 
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View attachment 191970

after this so much drama. people start to get the idea why overheating happens while canon already wrote down the cause of problem in their manual . :ROFLMAO:
Yes but if all you had to do was swap out the cfexpress every 15 mins and could continue to record for an hour imagine the response. Don’t buy 512GB cfexpress, but lots of small ones and an ice pack, lol

That would improve the viability of both cameras for a lot of people.
 
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From prograde site comparing cfexpress and sd express

“Heat Dissipation
The form factor of CFexpress Type B follows the original XQD physical size attributes. This larger form factor offers two benefits. First, its size allows more heat dissipation, but more importantly it utilizes a metal housing which allows heat to be drawn off of the enclosure. This allows the card to run cooler during extended high-speed recording sessions such as 4K RAW video capture (if used with the appropriate heat conducting host connector). The SD express form factor does not offer a provision for extracting heat through a host connector during high-speed operation.“
 

usern4cr

R5
CR Pro
Sep 2, 2018
992
1,396
Kentucky, USA
And from canon site


Smaller sandisk cards are not verified compatible with 8k. Also I didn’t realise 8k ipb could work with uhs ii slot
This Canon chart says that it can record 8K IPB 10 bit video to SD v90 or above card. Wouldn't this mean that you could record 10 bit 8K without any CFexpress card in the slot? I wonder if you record continuously for hours this way?
 

tomislavmoze

EOS M50
Aug 6, 2020
29
42
Great testing, thanks - certainly seems to be highlighting where the focus should be.

Would it be fair therefore to reverse the test. I think I have read that blowing cold air into the card socket makes no difference. Could you record 8k and see if you can get a quicker recovery time by just cooling the cfexpress card once removed from the camera (a lot cheaper than you buying another card)?

As the heated cfexpress card showed overheating then one might deduce the controller for the cfexpress is ok - as you say the camera was unused. So if you can cool the card, will that extend the times or will we find that even though the cfexpress card is clearly generating heat and when too hot prevents it being used, there are other components generating heat that the r5 can’t dissipate quick enough when recording 8k? Would love to be able to help you test, but mine is still stuck in pre-order phase...

Great work again, thanks.
I tried that, puting card to the fridge till it cooled down, but it did not help.
I guess it was just a bug since i could not replicate the situation and cooling the card did not help.
 
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adigoks

EOS 750D
Jul 12, 2020
58
66
PP finally gets in on the R5 clicks gravy train:


R5 is really news worthy.
I tried that, puting card to the fridge till it cooled down, but it did not help.
I guess it was just a bug since i could not replicate the situation and cooling the card did not help.

how about cooling both the camera & the card separately in the fridge with card door left open ?
because... after long time use the camera also got hot affected by the card.
 

bhf3737

---
CR Pro
Sep 9, 2015
629
1,279
Calgary, Canada
www.flickr.com
I had a situation where I filmed LQ 4k 30p for about 2 hours straight, in those two hours after about an hour I got locked out of all the HQ modes, and got the overheating warning when I switch to them. But an interesting thing happened. When I switched my battery after 2 hours it instantly gave me 20 minutes of 8k and 7 minuts of 4k120, althought 10 minutes before when I tried to use those modes while the first battery was in I could not do any filming in those modes. After 20 minutes of 8k it heated again I continued filming with the second battery in LQ 4K until it drain (it was an older battery so it lasted about an hour of footage) I tried to replicate the same thing with a third battery and I could not do it.
It seams that with the first changing of the batteries I trigger some bug or sort of a bug that managed to resetet the cameras heat control which definitely suggest that there is room in software for improvement.
Thanks for the testing. LP-E6 (N and H) battery pack has a smart chip to regulate and maintain voltage, temperature and performance. Temperature and other info from the chip is communicated to the camera and used by firmware to control the overall operation. Same with the CFexpress cards. The reading from thermal sensors for other components (e.g. IBIS) is more controlled but reading from batteries and memory cards that are interchangeable may wary and I think this is the source of trouble we see. Depending on the info from the CFex card and batteries we experience some random temperature management policy which is actually not random and decided by the firmware. I think the policies can be refined in later firmware updates.
 
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Max C

Canon 60D
Feb 9, 2020
112
128
I am on a job for the last couple days, should be done next Tuesday, effing weather is terrible... I haven't been able to read through this thread.

But I am so glad the community is testing the hell out of this camera and finding/sharing solutions to work around certain limitations in the R5.

It still sucks that you are gonna need to fork over about $1000 for an atomos and it's accessories for a $3900 flagship camera to fulfill certain shooting requirements. But at least there is a solution for some. Big thanks to these creators who are investing their time and energy to accurately inform us about these products.

Enjoy your shooting.
 
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Ramage

EOS R5
CR Pro
Aug 27, 2019
508
1,015
Why isn't Canon the ones providing this info?
Why would they? The work around involves using hardware from another manufacturer that they have no partnership with.

I have a tune for my car that provides more horsepower and better engine response and I have never heard anything from BMW about it.
 
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skp

5DIV, 7DII, 60D
CR Pro
Sep 20, 2014
51
49
Here's an interesting observation. I was just on Adorama looking for a CF Express card reader and noticed these reviews for Lexar's CF Express reader. I wonder if Canon's CF Express card slot is using similar hardware.

lexar cfexpress reader reviews.png
 
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