R5 recording limits temp/sensor correlations (continued)

[Peak freak]

Anyone know the Exif temps with the camera on / idle / stills for extended period?

Is it then actually too hot for HQ video modes, or is more that the 'clock is always ticking'?

you know .. this bring an interesting point even though it's sort of unrelated or reverse to what you are talking about.

is there a temperature threshold where the camera can no longer reliably perform stills photography without hitting a thermal wall after shooting x minutes of video.

maybe we're looking at this the wrong way. it's not all about video. (surprise).

but Canon is worried that if you shoot too much video, stills may be compromised over time - in other words, they are looking a temperatures, yes, but they are also prioritizing stills over video, so there's margins in there that are meant to protect the ability to shoot stills after video.

Hmm, good point.

Compromised stills performance due to heat is something I was worried about right at the start, but after early tests it appeared not to be an issue. Now if that is because Canon happens to know when it will be an issue and limits video (or heating) at that point... well, so be it. Protecting stills performance is paramount.

However, it is in Canon's interests to point this out so don't know why they haven't.

Locking you out of video modes (like 4K120) after extended stills use just seems like an 'odd' liability to have in a modern camera, but if there is a good reason for it, then no worries.

 

[traderjay]

Anyone know the Exif temps with the camera on / idle / stills for extended period?

Is it then actually too hot for HQ video modes, or is more that the 'clock is always ticking'?

you know .. this bring an interesting point even though it's sort of unrelated or reverse to what you are talking about.

is there a temperature threshold where the camera can no longer reliably perform stills photography without hitting a thermal wall after shooting x minutes of video.

maybe we're looking at this the wrong way. it's not all about video. (surprise).

but Canon is worried that if you shoot too much video, stills may be compromised over time - in other words, they are looking a temperatures, yes, but they are also prioritizing stills over video, so there's margins in there that are meant to protect the ability to shoot stills after video.

Hmm, good point.

Compromised stills performance due to heat is something I was worried about right at the start, but after early tests it appeared not to be an issue. Now if that is because Canon happens to know when it will be an issue and limits video (or heating) at that point... well, so be it. Protecting stills performance is paramount.

However, it is in Canon's interests to point this out so don't know why they haven't.

Locking you out of video modes (like 4K120) after extended stills use just seems like an 'odd' liability to have in a modern camera, but if there is a good reason for it, then no worries.

All these engineering decisions are directly from Tokyo, Canon HQ and only gets passed to the regions on a as "need" basis. So all the English coverage are second hand info.

I am certain if anyone can read Japanese and scour japanese photo forums there will be more up-to-date info for leaks. A while ago, we wanted to test one of Canon's 3D machine vision cameras for a robotic project, nobody outside of Canon Japan knows how to configure the unit, they had to fly in two engineers from Japan to Canada for two weeks.

--
Workstations - EPYC 7702 + 3950X || NVIDIA RTX 2080ti || Canon imagePROGRAF Pro-1000

 

[scrup]

Did Canon fix the loophole.

 

[Horshack]

In the beginning of his video today Gordon relays information provided to him by Canon regarding the thermal management on the R5. Here are the key points summarized:

1. Two internal temperature sensors, "near the AF and imaging sensor" and one for measuring external ambient temperature, near the ports.
2. R5 uses readings from all three sensors along with a timer to figure out when to report overheating and how much recording to allow while the camera cools down
3. Canon hasn't changed the temperature which overheating is reported but will now check the sensors more frequently, giving more accurate feedback and potentially allowing you to record again sooner, or for longer
4. The external ambient temperature now plays a bigger role so cooler surroundings may allow the camera to recover more quickly, so a fan or other active cooling could actually now become beneficial

#1 - Three internal temperature sensors

One sensor is described as being "near the AF". On previous Canon bodies the temperature report in the EXIF is from what's called the "EFIC temp" (source), which on previous Canon bodies was a secondary chip responsible for the lens interface and speedlites. Canon actual documented this chip in their 1DM3 technical whitepaper (page 33), where Canon refers to it as follows "EFIC as the interface for the lens and external Speedlite" and explicitly states it's located on the camera control board, separate from the image sensor and DIGIC. The verbiage Canon conveyed to Gordon sounds similar, so it may be safe to conclude the EXIF-reported temp is the EFIC temp, as it has been on previous Canon bodies.

The second sensor is described as being near the imaging sensor. If that's true then our efforts to induce the relative image sensor temperature from blackframe noise measurements (on the previous thread) may gain new importance as a proxy for this newly-disclosed temperature sensor.

The third sensor is described as measuring external ambient temperatures and is located near the ports.

#2 - How the three temperature sensors are used

Canon discloses all three sensors are used in combination a "timer". The fact they use a timer "in combination" with the sensors implies that 1) They're attempting to project the temperature ramp (both up and down), perhaps as part of a hysteresis algorithm that's attempting to account for temperature lags and/or 2) Enforcing a total heat exposure metric (temperature x time, ie how long the chips are exposed to heat rather than peak temperature), perhaps as an effort to ensure longevity of the internal ICs.

#3 - Sampling the sensors more frequently for more accurate feedback [presumably into their thermal algorithm]

This one strikes me as very peculiar. If you look at all the data we've collected, which includes calculations for the rate of temperature change per minute (4K30 HQ ramp-example and 8K ramp-down example) the rate of temperature change rarely exceeds 1c to 2c/min - the fastest I've seen it climb is approx 3c/min for a single 8K test. Which begs the question - how fast were they sampling the temperature before and how could it not be fast enough to track this rate of ramp? Why would they not sample the temperature at least every 15 or 30 seconds? And regardless of how often they sample, the rate is pretty linear on both the way up and down, so why would more samples yield "more accurate feedback" since the trend line would be the same?

#4 - External ambient sensor now plays a bigger role, esp for cooling calculations

This one is interesting. It implies they're partly relying on the ambient temperature to project the rate of cooling rather than relying exclusively on the two internal sensors to directly measure that trend/rate, and even more so with the new firmware. I assume they're comparing the rate of decline of the internal sensors relative to the ambient, either by some dynamic heuristic or a lookup table they built during the R5's design/testing, either of which attempts to use that relationship to project the temperature at points in the future.

Initial Thoughts

On balance the new thermal details provided by Canon and the description of how that logic changed in today's firmware sounds a bit contrived to me. Thermals must have been one of the biggest challenges during the development and testing phases of the project. How could it be that they overlooked some elemental relationships between the three sensors and also not have sampled them frequently enough? It doesn't make much sense to me. IMO it sounds like misdirection to simply obscure the fact they may have simply loosened the reins a bit on the temperatures allowed, either peak or more likely total heat (temp x time). The fact the cooldown periods were most affected by the new firmware (shortened) suggest they're simply allowing the camera to operate warmer for longer. The fact the temps usually plateau near the end of the recording time allowed also supports the notion it's a total heat consideration rather than a peak or "overheating" consideration.

 

[rrc1967]

On balance the new thermal details provided by Canon and the description of how that logic changed in today's firmware sounds a bit contrived to me. Thermals must have been one of the biggest challenges during the development and testing phases of the project. How could it be that they overlooked some elemental relationships between the three sensors and also not have sampled them frequently enough? It doesn't make much sense to me. IMO it sounds like misdirection to simply obscure the fact they may have simply loosened the reins a bit on the temperatures allowed, either peak or more likely total heat (temp x time). The fact the cooldown periods were most affected by the new firmware (shortened) suggest they're simply allowing the camera to operate warmer for longer. The fact the temps usually plateau near the end of the recording time allowed also supports the notion it's a total heat consideration rather than a peak or "overheating" consideration.

yes, but all of these could have been caught by Canon in their final pre-production testing but too late to affect the first wave of cameras out the door.

Faulty assumptions do occur in software development.

 

[CanonshooterRF212]

We need a subscribe button to get alerts when certain forum members post. Really appreciate the posts, Horshack.

 

[n0tinus3]

could the ambient sensor be in the hole above the USB-C?

 

[Chris Giles]

USA firmware is up i just upgraded my camera! Based on the review he is able to record many more shorter clips of 4k 120 than before because the recovery time has improved due to better sensor reading.

I really enjoyed all the technical discussions here and the firmware proved there is really no conspiracy theory that all the trolls are alluding to. With what is in the r5 and the form factor unlimited 8k raw is impossible.

<Record scratch>

Had it not of been for all the upset and conspiracy theories in the first place would Canon of made any changes?

 

[Chris Giles]

could the ambient sensor be in the hole above the USB-C?

Possibly, the next hack will be someone firing a can of compressed air into it via a straw.

 

[TN Args]

This is a continuation of the thread here.

Recent Recap

A lot has transpired since that thread reached its conclusion - an owner in China was able to reset the thermal timer and bypass the cooling-off period by removing the clock battery. A few weeks prior to that I had proposed an experiment to do the same by inhibiting the camera's ability to save its thermal management to NVRAM by removing the main battery. I repeated proposed the same experiment here with more details. Once word of the China clock-battery spread (thanks to EOSHD) I was finally able to get a volunteer for the main-battery experiment, which was successfully performed by J Marus ,then later by Matt Granger, Electroholic Anonymous, and Andrew Reid, the latter two of which demonstrated recording 8K for 50 minutes over multiple battery-removal sessions without any special cooling/fridge tests.

I'm going to keep this thread focused on the technical investigation and not spend too much on theories centered around marketing/segmentation/crippling. Those are well handled in other forums such as EOSHD and YouTube.

New Revelations - workaround for corrupt video file

While the hack was important in revealing new details about Canon's thermal management it's not meant to serve as an actual workaround since it requires pulling the battery while the video is still be recording (otherwise the camera saves the thermal state to NVRAM when the user stops a recording). This renders the video unplayable/unusable. Instead of a fully-formed .MP4 file the technique leaves a .DAT file, which represents the mdat atom of the video file (video+audio frames) but is missing all the MP4 container metadata to play or use the fie.

While working on tools to reconstruct the missing MP4 container metadata, an EOSHD forum poster the name of J- proposed a brilliant workaround to use FAT32-formatted cards, which would force the camera to split up a continuous recording into 4GB splits (due to FAT32's 4GB per-file limitation). It wasn't clear if this technique would avoid the NRAM-saving that's seen when stopping a recording. After experimenting on my Canon RP I found it does avoid the NVRAM when writing the 4GB splits, and more importantly, it was later verified on a R5 by Electroholic Anonymous here.

So far this FAT32 trick only works on SD cards - neither Electroholic Anonymous or Hoka Key have been able to get the camera to accept a FAT32-formatted CFE card. Normally the camera will only format cards <= 32GB as FAT32, using exFAT for larger capacity cards. This limitation has been worked around by formatting the cards under Linux - Windows 10 wont let your format cards > 32GB as FAT32 (but will mount them) and the camera wont accept FAT32 cards formatted under OSX. More details here.

So there is now a plausible workaround that includes saving the entire recorded video sans the last 4GB lost after a battery pull (which is only about 45 seconds for an 8K video).

I always thought your name was Hor-shack but now I realise it’s Hors-hack.

 

[n0tinus3]

could the ambient sensor be in the hole above the USB-C?

Possibly, the next hack will be someone firing a can of compressed air into it via a straw.

air? pouring liquid nitrogen inside would be much more effective...

 

[Chris Giles]

could the ambient sensor be in the hole above the USB-C?

Possibly, the next hack will be someone firing a can of compressed air into it via a straw.

air? pouring liquid nitrogen inside would be much more effective...

Good idea, maybe a liquid nitrogen dip tank for the whole thing. Just to be sure

 

[Electroholic Anonymous]

could the ambient sensor be in the hole above the USB-C?

Possibly, the next hack will be someone firing a can of compressed air into it via a straw.

I was foolish enough to do that two weeks ago, and also directly in the open card door, and at least with the 1.0.0 firmware that had almost zero impact, it cooled the CFE card by some 10 to 20 degrees Celsius, but that was about it. I used the 'scotch tape and toothpick' method on the card door. Leaving the door open has also almost zero impact. However, I do think leaving the door open while cooling down for half an hour has an effect, albeit small on the 1.0.0 fw. I have not tested this in detail however.

 

[Electroholic Anonymous]

This is the video of the 100+ minutes 8K24 IPB 680Mbps run on FAT32 128GB SD cards with 5 battery pulls on FW 1.0.0 as reported here at the start of the thread.

 

[Zeee]

On balance the new thermal details provided by Canon and the description of how that logic changed in today's firmware sounds a bit contrived to me. Thermals must have been one of the biggest challenges during the development and testing phases of the project. How could it be that they overlooked some elemental relationships between the three sensors and also not have sampled them frequently enough? It doesn't make much sense to me. IMO it sounds like misdirection to simply obscure the fact they may have simply loosened the reins a bit on the temperatures allowed, either peak or more likely total heat (temp x time). The fact the cooldown periods were most affected by the new firmware (shortened) suggest they're simply allowing the camera to operate warmer for longer. The fact the temps usually plateau near the end of the recording time allowed also supports the notion it's a total heat consideration rather than a peak or "overheating" consideration.

yes, but all of these could have been caught by Canon in their final pre-production testing but too late to affect the first wave of cameras out the door.

Faulty assumptions do occur in software development.

You do realize they released a camera like no other during a global pandemic that shut the world down. I can just imagine the pressure everyone was under. No one seems to be taking this under consideration.

 

[Zeee]

USA firmware is up i just upgraded my camera! Based on the review he is able to record many more shorter clips of 4k 120 than before because the recovery time has improved due to better sensor reading.

I really enjoyed all the technical discussions here and the firmware proved there is really no conspiracy theory that all the trolls are alluding to. With what is in the r5 and the form factor unlimited 8k raw is impossible.

<Record scratch>

Had it not of been for all the upset and conspiracy theories in the first place would Canon of made any changes?

Yes. From user reviews which happens all of the time. The reset time and a few other things needed to be looked at. Conspiracy theorists that blew this way out of proportion wanted a professional cinema camera and they will never get it out of the R5. For some reason no matter how many times people would say (and said months before) you will never be able to run 8K continuously with a small body with no ventilation it didn't matter.

 

[Jotoco]

On balance the new thermal details provided by Canon and the description of how that logic changed in today's firmware sounds a bit contrived to me. Thermals must have been one of the biggest challenges during the development and testing phases of the project. How could it be that they overlooked some elemental relationships between the three sensors and also not have sampled them frequently enough? It doesn't make much sense to me. IMO it sounds like misdirection to simply obscure the fact they may have simply loosened the reins a bit on the temperatures allowed, either peak or more likely total heat (temp x time). The fact the cooldown periods were most affected by the new firmware (shortened) suggest they're simply allowing the camera to operate warmer for longer. The fact the temps usually plateau near the end of the recording time allowed also supports the notion it's a total heat consideration rather than a peak or "overheating" consideration.

yes, but all of these could have been caught by Canon in their final pre-production testing but too late to affect the first wave of cameras out the door.

Faulty assumptions do occur in software development.

You do realize they released a camera like no other during a global pandemic that shut the world down. I can just imagine the pressure everyone was under. No one seems to be taking this under consideration.

 

[Zeee]

This is the video of the 100+ minutes 8K24 IPB 680Mbps run on FAT32 128GB SD cards with 5 battery pulls on FW 1.0.0 as reported here at the start of the thread.

It is not good for electronics to run at 62 Celsius for long periods of time.

 

[Zeee]

On balance the new thermal details provided by Canon and the description of how that logic changed in today's firmware sounds a bit contrived to me. Thermals must have been one of the biggest challenges during the development and testing phases of the project. How could it be that they overlooked some elemental relationships between the three sensors and also not have sampled them frequently enough? It doesn't make much sense to me. IMO it sounds like misdirection to simply obscure the fact they may have simply loosened the reins a bit on the temperatures allowed, either peak or more likely total heat (temp x time). The fact the cooldown periods were most affected by the new firmware (shortened) suggest they're simply allowing the camera to operate warmer for longer. The fact the temps usually plateau near the end of the recording time allowed also supports the notion it's a total heat consideration rather than a peak or "overheating" consideration.

yes, but all of these could have been caught by Canon in their final pre-production testing but too late to affect the first wave of cameras out the door.

Faulty assumptions do occur in software development.

You do realize they released a camera like no other during a global pandemic that shut the world down. I can just imagine the pressure everyone was under. No one seems to be taking this under consideration.

Sony a7s3, black magic 12k, red komodo....

The Sony is nothing. What challenge was there with a 12mp camera? I'm not familiar with the others. Where they groundbreaking? Did they do something outstanding that no other cameras can?

 

[jnd]

This is the video of the 100+ minutes 8K24 IPB 680Mbps run on FAT32 128GB SD cards with 5 battery pulls on FW 1.0.0 as reported here at the start of the thread.

It is not good for electronics to run at 62 Celsius for long periods of time.

Who told you? There are couple guys repeating this nonsense and I bet they know nothing about electronics. 60 degrees C is only bad for the amount of noise you will get from hot sensor and AD converters. Silicon has no problems working over 100 C and processors work in these temperatures. Their limit is based on leakage currents getting too high, not because of permanents damage. You can get automotive parts specified up to 125 C of ambient temperature. Even electrolytic capacitors are rated for 105 C and the whole board doesn't behave as one big hotspot so engineers can place more sensitive components on the side where it will be cooler.

Running at high temperature is fine, I mean where I work we have 20 year old boards running just fine in enclosed boxes even in summer days on hot streets. You get more problems with repeated temperature cyclling inducing stress into parts. But that would be more than this barely 40 degree difference, that's even in range of bog standard cheap consumer components. Have you touched Canon chargers in middle of charging? They get uncomfortably hot so much that it's hard to hold in hand and that is official Canon hardware. I tried both one for RP and one for R5. It suprised me because deisgning charger that gets so hot with just 8W of rated output is bad design but aparently it passed all the design reviews.