Canon EOS R6 buffer depth issue

AdamBotond

EOS M6 Mark II
Mar 31, 2016
79
6
Hi there,
My R6 arrived a week ago and its a love at first sight. However, I noticed that buffer depth seems to be narrower than I expected. At he right bottom corner it shows 65 shots to go, which I have tested... no matter how slow or fast SD card I am using it with. Its same number using my Sandisk Extreme Pro UHS-II (ws: 260 MB/s) and my older Sony UHS-I card. While buffer depth of 65 pics could rarely be an issue, given a fast card I assumed something closer to 240 raw shots claimed by Canon.
Am I missing something here? Any insight on this?

Thanks in advance.

All the best,
Adam
 

Joules

EOS R
CR Pro
Jul 16, 2017
1,113
1,252
Hamburg, Germany
I thought the number indicates the actual memory of the camera, and what we usually call buffer is referring to the combination of camera memory and card speed.

So,the number in the corner should drop faster during bursts when you use a slow SD card.

I may be wrong here though. Have you tested how many shots in a row you are actually getting with each camera?
 

AdamBotond

EOS M6 Mark II
Mar 31, 2016
79
6
Have you tested how many shots in a row you are actually getting with each camera?
Its slowing down after reaching the indicated 65 shots. I tried using various settings, but it did not make a difference. Latest firmware used.
 

zim

EOS 5D Mark IV
CR Pro
Oct 18, 2011
1,988
176
What lens and exposure settings are you using? I don't have the R6 but those things always contribute
 

AdamBotond

EOS M6 Mark II
Mar 31, 2016
79
6
What lens and exposure settings are you using? I don't have the R6 but those things always contribute
24-70 2.8L, 400 F4 DO IS II, doesnt matter. Also, changing exposure doesn't change a thing. Leaving the lens cap on, setting up at iso 100, shutter 1/8000, as Bryan at TDP tested doesn't make a difference, either. Weird...
 

YuengLinger

Sufficiently Pixilated
CR Pro
Dec 20, 2012
3,109
1,374
USA
24-70 2.8L, 400 F4 DO IS II, doesnt matter. Also, changing exposure doesn't change a thing. Leaving the lens cap on, setting up at iso 100, shutter 1/8000, as Bryan at TDP tested doesn't make a difference, either. Weird...
Yes, agreed. When you say it is slowing down as it gets to 65 shots, by how much do you mean? Do you see the remaining shot count dropping to zero as this happens? Or it always stays 65?
 

AdamBotond

EOS M6 Mark II
Mar 31, 2016
79
6
I did some retesting. Seemingly, the number indicating the buffer capacity is stuck at 65, however this number is true only at high iso. Leaving the lens cap on with the fast sandisk extreme pro card, shutter at 1/1250, iso 100, I was shooting with no limits practically (I stoped pressing the shutter after 1 min, after taking 720+ pitchblack shots). Also, taking the R6 into a real world scenerio in the garden, I had a burst of 270 shots at iso 1000, 1/800, before I reached the buffer limit after 12 seconds. So settings, exposure, scenario and most importantly file sizes do make a difference after all.
However, the number of shots in the buffer are indicated inaccurately. I expected this number to be 99+, when the camera is capable of doing 200+ shots in burst mode. It shows 65 no matter what, but I can live with that. :)
 

Mt Spokane Photography

I post too Much on Here!!
CR Pro
Mar 25, 2011
16,364
1,370
If set to FV, those buffer numbers drop a lot. My R5 with a V60 UHS II card reads 45 raws in FV and 66 in any of the other modes. 66 is the number for a UHS I card. I tried two differenr brands of UHS II cards, that number does not change from 66. I wasn't going to shoot 80 shots off to see exactly how many, 66 is quite a lot.

Make sure the camera is not in FV. I have no idea why that would change buffer depth.
 

koenkooi

EOS R
CR Pro
Feb 25, 2015
1,377
1,170
Hi there,
My R6 arrived a week ago and its a love at first sight. However, I noticed that buffer depth seems to be narrower than I expected. At he right bottom corner it shows 65 shots to go, which I have tested... no matter how slow or fast SD card I am using it with.[..]
From what I understand, that number is how many shots fit in the internal buffer, the RAM in the camera. When that hits zero you will by writing directly to the card.
If that number drops during shooting, it means your card can't keep up. If the number stays the same, you card can write pictures as fast as the camera can take them.
 

AdamBotond

EOS M6 Mark II
Mar 31, 2016
79
6
My R6 was only in manual mode for the tests. What interesting is that in ideal conditions the camera took 215 or even more pics in burst before hitting the limit of the buffer and counting down from the indicated 65 down to 0 for another 65 shots continously. When it hit 0, it ultimately slowed down, of course. So it took 270 shots in burst at 12 fps with no slowing down, even though it showed 65. That's why I have no idea what no. 65 truly represents.

65 could be the number of shots in worst case scenario, as when I was testing this extreme in high iso (20.000), 65 shots seemed to be fairly accurate.

Thanks for your inputs!
 

Joules

EOS R
CR Pro
Jul 16, 2017
1,113
1,252
Hamburg, Germany
That's why I have no idea what no. 65 truly represents
As I and koenkool tried to point out, it likely represents how many shots the camera's internal memory can hold. In other words, you could essentially take that many shots even without having any card at all in the camera. Of course, that is not an option Canon provides. But with a card installed, as long as the card can sutain a write speed higher than the speed at which images are captured, the internal memory doesn't fill up. Otherwise, it will fill up, at a speed that depends on the difference between the card's write speed and the rate at which images are captured.
 

AdamBotond

EOS M6 Mark II
Mar 31, 2016
79
6
As I and koenkool tried to point out, it likely represents how many shots the camera's internal memory can hold. In other words, you could essentially take that many shots even without having any card at all in the camera. Of course, that is not an option Canon provides. But with a card installed, as long as the card can sutain a write speed higher than the speed at which images are captured, the internal memory doesn't fill up. Otherwise, it will fill up, at a speed that depends on the difference between the card's write speed and the rate at which images are captured.
Joules, I got all of that. It just doesn't make much sense to me. First of all, if this number refers to internal memory of the camera, which is independent from the speed of cards as you say, I would assume that all R6 unit would have nr. 65 (or this number would change by settings and/or exposure, which it doesn't on my unit). But I saw users having "buffer depth" indicator "99" in the viewfinder.

Also, if this refers to only internal memory of the camera, its just not informative as for how many shots you can actually take in a burst. You have no idea whether you could take 65 or 700+ shots before slowing down, I have tested it, therefore that number indicater is pretty much meaningless to me. Again, I can live with that, knowing that this camera is capable of 200+ shots or even more in a real life situation.
 

Kit.

EOS 5D Mark IV
Apr 25, 2011
2,011
1,355
Joules, I got all of that. It just doesn't make much sense to me. First of all, if this number refers to internal memory of the camera, which is independent from the speed of cards as you say, I would assume that all R6 unit would have nr. 65 (or this number would change by settings and/or exposure, which it doesn't on my unit). But I saw users having "buffer depth" indicator "99" in the viewfinder.
If someone shoots JPEG, the files are smaller and the buffer can hold more of them.

Also, if this refers to only internal memory of the camera, its just not informative as for how many shots you can actually take in a burst. You have no idea whether you could take 65 or 700+ shots before slowing down, I have tested it, therefore that number indicater is pretty much meaningless to me. Again, I can live with that, knowing that this camera is capable of 200+ shots or even more in a real life situation.
There is no guarantee that the current write speed of the SD card is its sustained write speed. The camera should not use it for computations of guaranteed full burst lenght.

When we were testing SD cards as a DVR storage media for our IPTV boxes, some card models were periodically freezing for up to 2 seconds during writes.
 

Joules

EOS R
CR Pro
Jul 16, 2017
1,113
1,252
Hamburg, Germany
First of all, if this number refers to internal memory of the camera, which is independent from the speed of cards as you say, I would assume that all R6 unit would have nr. 65 (or this number would change by settings and/or exposure, which it doesn't on my unit). But I saw users having "buffer depth" indicator "99" in the viewfinder.
I would assume changing the recording type (JPEG in various qualities, RAW, C-RAW) would influence the number displayed. If so, that may explain the difference between your results and what you saw with other users.

I believe Canon are only putting a number up there that they can be fairly certain of. They nlknow their algorithms and hardware, so they can calculate the number based on the internal memory and average file size expected for a given recording type. The cards they'd have to benchmark each time they are inserted. They certainly could do that, but I think with how conservative they are, they don't want to get blamed if card manufacturers pull some tricks like having a separate buffer on the card.
 

AdamBotond

EOS M6 Mark II
Mar 31, 2016
79
6
I believe Canon are only putting a number up there that they can be fairly certain of. They nlknow their algorithms and hardware, so they can calculate the number based on the internal memory and average file size expected for a given recording type. The cards they'd have to benchmark each time they are inserted. They certainly could do that, but I think with how conservative they are, they don't want to get blamed if card manufacturers pull some tricks like having a separate buffer on the card.
Makes sense, that's what I was thinking. This number is more like an "worst case scenario" indicator.
Thank you guys!