5D MkIII buffer

[mikejkay]

I am still getting to grips with my 5DIII and I am, in general, very pleased with it. However, I started playing with bracketed shots at different exposures with my old 7D and found this feature very usefull. One of the features that led to my buying the 5DIII was the ability to take 7 bracketed shots. However, I find that I cannot do this, the camera will only rattle off 6 shots. I can get the 7 exposures if I reduce to mRAW which rather negates one of the benefits of the 5DIII. I shoot RAW to the CF card and JPEG to the SD card. Reducing the JPEG to minimum makes no difference.

My fastest CF card is 300x and my SD cards are newer Class 6 UHS-1. Will faster CF cards solve the problem?

 

[mackguyver]

I am still getting to grips with my 5DIII and I am, in general, very pleased with it. However, I started playing with bracketed shots at different exposures with my old 7D and found this feature very usefull. One of the features that led to my buying the 5DIII was the ability to take 7 bracketed shots. However, I find that I cannot do this, the camera will only rattle off 6 shots. I can get the 7 exposures if I reduce to mRAW which rather negates one of the benefits of the 5DIII. I shoot RAW to the CF card and JPEG to the SD card. Reducing the JPEG to minimum makes no difference.

My fastest CF card is 300x and my SD cards are newer Class 6 UHS-1. Will faster CF cards solve the problem?

Yes, a CF card that writes at 60MB/s (important to note the write speed - most cards write much slower than the advertised _____x read speed) will allow you to write 19 RAW files before the buffer fills and starts slowing down. A UDMA 7 CF card that writes at 150MB/s (just bought one) lets you write 35 frames before slowing. The SD card slot on the 5DIII is an older standard and buying anything over 30 to 45MB/s write speed is a waste.

I'd buy a 800x or higher CF card (that will give you a 75MB/s write speed or higher) if I were you, that should solve your problem.

 

[cdn_photog]

I had the same issue when I went from a 7D to a 5D3. I think my old card was a SanDisk UDMA 6 at 90 MB/s, I bought this UDMA 7 at 160 MB/s which was a huge improvement in the 5D3.

http://www.adorama.com/IDSCFEP4K32.html?sub=forum&utm_term=Other&utm_medium=Affiliate&utm_campaign=Other&utm_source=rflaid64393

 

[mikejkay]

cdn_photog

Are you saying that a UDMA 6 card at 90 MB/s was unable to cope with 7 full size RAW shots? mackguyver suggests that a 60MB/s card will do the trick (for a single burst).

 

[Drizzt321]

Also try not writing anything to the SD card. Even though it's JPGs, it does take additional CPU to process to JPG, then also write the (moderately large at Large+Fine) JPG files, and the 5d3's SD card is an old spec, and SLOW. Try with just your CF card, and the faster the better. A UDMA7 is best, even if it's not the fastest cards (300-600x), as UDMA7 brings TRIM support which will help keep peak speeds up when you delete/format the card in the camera which can talk UDMA7.

 

[Don Haines]

cdn_photog

Are you saying that a UDMA 6 card at 90 MB/s was unable to cope with 7 full size RAW shots? mackguyver suggests that a 60MB/s card will do the trick (for a single burst).

It helps a lot if you give the make and model of the cards.....

The printed specs are ALWAYS for read speed, unless they also include a second number for write speed. You can find cards that are 90MB/s read speed, yet only 20MB/s write speed..

Your 300X card reads at 45MB/second, look up how fast it writes.... you will be surprised...

Your class 6 SD card will not write at 10MB/s.

 

[cdn_photog]

@mikejkay I wasn't doing 7 bracketed shots at a time with the old card, and I sold it with the 7D so I can't remember the exact specs, but I was running into buffer issues in that it was slowing down earlier than the 5D3 specs state the camera is capable of. And noticeably slower than the 7D's buffer. I am very happy with the speed of the UDMA 7 card I have now. It wasn't cheap, but having spend that much on a camera cheaping out on the card didn't seem like a good idea.

I have done 7 bracketed shots since then, with the faster card, with no buffer issues.

 

[mikejkay]

Thanks ton all. Looks like UDMA 7 is the way to go. Pity I spent all my money on the 5DIII...and the 'L' glass. Sticks in the gullet a bit to spend £100+ on a memory card. Unfortunately, I carry 1x32GB and 3x16GB as I am aay for several months at a time.

 

[Drizzt321]

Thanks ton all. Looks like UDMA 7 is the way to go. Pity I spent all my money on the 5DIII...and the 'L' glass. Sticks in the gullet a bit to spend £100+ on a memory card. Unfortunately, I carry 1x32GB and 3x16GB as I am aay for several months at a time.

While CF cards are generally more durable than SD cards, they do eventually wear out and do need eventual replacement. Unless you need the CF card as fast as possible, you can just keep using your older ones. Try disabling the JPG to SD, that might free up that last bit of buffer you need to get the full 7 shots.

What's stopping you from just waiting until the buffer clears that for the first image and shooting that last of the bracketed shots? Doing a bracket like that won't help with lots of action, and more for things basically sitting still, which should give you that extra few seconds to make sure to get the last bracketed shot.

 

[mikejkay]

With the responses on this thread, a bit more reading and some experimenting I have confirmed that I can get 7 bracketed shots if I only use the CF card in slot 1. This does not seem to be because of the amount of data or the processing overhead but more that the SD slot has been crippled for some reason only known to Canon! This approach would mean that I would have to manually copy my files to the SD card. I would prefer not to have to do this as I am a firm believer in "Sods Law" and in reliable backing up I'm not sure that a super fast CF car would solve the problem as I would still be restricted by the SD card slot write speed. In any event it seems that the 5DIII might not be fully compatible with UDMA 7, but only UDMA 6. Perhaps someone could confirm this (or not!).

This leaves two other options: i) restrict my self to 5 shot bracketing and ii) the suggestion to take the 7th bracketed shor 'manually'. 5 bracketed shots is still an improvement on the 7D.

 

[cdn_photog]

@mikejkay I just did a quick test with the UDMA 7 160MB/s CF card set to raw, and SD card set to JPEG S1, and it really slowed down the buffer for 7 bracketed shots. The camera took all 7 shots, but the 'busy' symbol came up on the screen and there was a definite lag which does not occur when the SD card is removed.

 

[mackguyver]

@mikejkay I just did a quick test with the UDMA 7 160MB/s CF card set to raw, and SD card set to JPEG S1, and it really slowed down the buffer for 7 bracketed shots. The camera took all 7 shots, but the 'busy' symbol came up on the screen and there was a definite lag which does not occur when the SD card is removed.

You don't have to remove the SD card, just don't write to it. It's hardware limited to 30MB/s which is "Class 10", whereas the CF card is UDMA7, so it's MUCH faster. Canon didn't cripple the SD slot, it was the fastest SD standard available when the camera was designed.

 

[Drizzt321]

@mikejkay I just did a quick test with the UDMA 7 160MB/s CF card set to raw, and SD card set to JPEG S1, and it really slowed down the buffer for 7 bracketed shots. The camera took all 7 shots, but the 'busy' symbol came up on the screen and there was a definite lag which does not occur when the SD card is removed.

You don't have to remove the SD card, just don't write to it. It's hardware limited to 30MB/s which is "Class 10", whereas the CF card is UDMA7, so it's MUCH faster. Canon didn't cripple the SD slot, it was the fastest SD standard available when the camera was designed.

Yup, this exactly. And even if it slows down, you can still take that 7th shot, you just need to wait a few seconds for it to stop being busy and capable of taking another photo for it to then take that 7th bracketed shot. You don't have to have the camera in continuous shutter for the bracketing, and you don't have to take them back to back. You can pause in the middle of each one if you want.

 

[mikejkay]

mackguyver, Class 10 write speed is not 30MB/s it's a minimum of 10MB/s. I have dome a lot of work testing SD and microSD cards mainly because I was stupid enough to buy a SanDisk Ultra card which has 30MB/s emblazoned in large letters on the front. I was rather perplexed with the slow write speeds that I got so I tested the card. I used CrystalDiskMark, DiskSpeed.exe, h2testw and Bench32.exe. The real time write speeds in Windows 7 varied enormously but were mostly less than 10MB/s and averaged 4 to 5MB/s. The ONLY write speed result from all the tests that I carried out was 10.07MB/s from CrystalDiskMark. Needless to say SanDisk say that this single marginal and isolated result means that the card is within specification.

-----------------------------------------------------------------------
CrystalDiskMark 3.0.3 x64 (C) 2007-2013 hiyohiyo
Crystal Dew World : http://crystalmark.info/
-----------------------------------------------------------------------
* MB/s = 1,000,000 byte/s [SATA/300 = 300,000,000 byte/s]

Sequential Read : 44.554 MB/s
Sequential Write : 10.071 MB/s
Random Read 512KB : 0.000 MB/s
Random Write 512KB : 0.000 MB/s
Random Read 4KB (QD=1) : 0.000 MB/s [ 0.0 IOPS]
Random Write 4KB (QD=1) : 0.000 MB/s [ 0.0 IOPS]
Random Read 4KB (QD=32) : 0.000 MB/s [ 0.0 IOPS]
Random Write 4KB (QD=32) : 0.000 MB/s [ 0.0 IOPS]

Test : 1000 MB [G: 91.1% (54.2/59.4 GB)] (x1)
Date : 2014/03/06 18:46:48
OS : Windows 7 Home Premium SP1 [6.1 Build 7601] (x64)
SANDISK_64GB_SDXC

I think that it is of interest that three Samsung Class 6 SD cards gave write speeds of 14-15MB/s and my Toshiba Class 10 microSD card gave a write speed of 14.6MB/s.

Moral: Don't believe the hype about SanDisk being a top class manufacturer!

 

[mackguyver]

mackguyver, Class 10 write speed is not 30MB/s it's a minimum of 10MB/s. I have dome a lot of work testing SD and microSD cards mainly because I was stupid enough to buy a SanDisk Ultra card which has 30MB/s emblazoned in large letters on the front. I was rather perplexed with the slow write speeds that I got so I tested the card. I used CrystalDiskMark, DiskSpeed.exe, h2testw and Bench32.exe. The real time write speeds in Windows 7 varied enormously but were mostly less than 10MB/s and averaged 4 to 5MB/s. The ONLY write speed result from all the tests that I carried out was 10.07MB/s from CrystalDiskMark. Needless to say SanDisk say that this single marginal and isolated result means that the card is within specification.

-----------------------------------------------------------------------
CrystalDiskMark 3.0.3 x64 (C) 2007-2013 hiyohiyo
Crystal Dew World : http://crystalmark.info/
-----------------------------------------------------------------------
* MB/s = 1,000,000 byte/s [SATA/300 = 300,000,000 byte/s]

Sequential Read : 44.554 MB/s
Sequential Write : 10.071 MB/s
Random Read 512KB : 0.000 MB/s
Random Write 512KB : 0.000 MB/s
Random Read 4KB (QD=1) : 0.000 MB/s [ 0.0 IOPS]
Random Write 4KB (QD=1) : 0.000 MB/s [ 0.0 IOPS]
Random Read 4KB (QD=32) : 0.000 MB/s [ 0.0 IOPS]
Random Write 4KB (QD=32) : 0.000 MB/s [ 0.0 IOPS]

Test : 1000 MB [G: 91.1% (54.2/59.4 GB)] (x1)
Date : 2014/03/06 18:46:48
OS : Windows 7 Home Premium SP1 [6.1 Build 7601] (x64)
SANDISK_64GB_SDXC

I think that it is of interest that three Samsung Class 6 SD cards gave write speeds of 14-15MB/s and my Toshiba Class 10 microSD card gave a write speed of 14.6MB/s.

Moral: Don't believe the hype about SanDisk being a top class manufacturer!

I was looking at a bad source on the 25MB/s for Class 10 - you're right about it being 10MB/s minimum. The more important factor is the bus speedhttps://www.sdcard.org/consumers/speed/bus_speed/, which is limited to 25MB/s, I believe, assuming the 5DIII has a "High Speed" bus interface:
https://www.sdcard.org/consumers/speed/bus_speed/

I'm not surprised about Samsung - they and Sandisk are the industry leaders in flash memory right now. I'm not sure if there's a lot of value in running tests on your PC if you're interested in the in-camera performance, but at least it shows you what the card + card reader + PC bus performance is capable of achieving. Also, remember that the speed on the cards/packaging is a max speed under ideal "test" conditions. Personally I think the SD card slot on the 5DIII isn't of much use other than for back ups and dual recording if you don't shoot in high speed mode. You're better off spending your money on a good CF card as the performance is significantly higher in the 5DIII.

As far as "hype", I buy Sandisk and Lexar primarily because they are tough, reliable, and perform significantly better than most of the off-brands in my testing (I have several "free" cards I've received over the years). That's not to say Samsung, Toshiba, Delkin or some of the other brands are bad (they aren't), but there are plenty of low end cards out there.

I see little point in saving money on a card (even if it has higher performance) and losing photos in the long run. It only has to happen to you once and you'll understand. In 2001, I lost an entire trip's worth of photos that I'll never get back thanks to a cheap SD card that couldn't be recovered by anyone. It was devastating and I'd have paid $1,000 for a memory card had I known I would lose those photos. I've heard many similar stories, and the vast majority of them involve a brand other than Sandisk or Lexar.

 

[Drizzt321]

mackguyver, Class 10 write speed is not 30MB/s it's a minimum of 10MB/s. I have dome a lot of work testing SD and microSD cards mainly because I was stupid enough to buy a SanDisk Ultra card which has 30MB/s emblazoned in large letters on the front. I was rather perplexed with the slow write speeds that I got so I tested the card. I used CrystalDiskMark, DiskSpeed.exe, h2testw and Bench32.exe. The real time write speeds in Windows 7 varied enormously but were mostly less than 10MB/s and averaged 4 to 5MB/s. The ONLY write speed result from all the tests that I carried out was 10.07MB/s from CrystalDiskMark. Needless to say SanDisk say that this single marginal and isolated result means that the card is within specification.

-----------------------------------------------------------------------
CrystalDiskMark 3.0.3 x64 (C) 2007-2013 hiyohiyo
Crystal Dew World : http://crystalmark.info/
-----------------------------------------------------------------------
* MB/s = 1,000,000 byte/s [SATA/300 = 300,000,000 byte/s]

Sequential Read : 44.554 MB/s
Sequential Write : 10.071 MB/s
Random Read 512KB : 0.000 MB/s
Random Write 512KB : 0.000 MB/s
Random Read 4KB (QD=1) : 0.000 MB/s [ 0.0 IOPS]
Random Write 4KB (QD=1) : 0.000 MB/s [ 0.0 IOPS]
Random Read 4KB (QD=32) : 0.000 MB/s [ 0.0 IOPS]
Random Write 4KB (QD=32) : 0.000 MB/s [ 0.0 IOPS]

Test : 1000 MB [G: 91.1% (54.2/59.4 GB)] (x1)
Date : 2014/03/06 18:46:48
OS : Windows 7 Home Premium SP1 [6.1 Build 7601] (x64)
SANDISK_64GB_SDXC

I think that it is of interest that three Samsung Class 6 SD cards gave write speeds of 14-15MB/s and my Toshiba Class 10 microSD card gave a write speed of 14.6MB/s.

Moral: Don't believe the hype about SanDisk being a top class manufacturer!

The other question to ask...is the card freshly low-level formatted? Or has it been written to previously? With SD cards, you need to low-level format (e.g. clear out all the previously written blocks) if you want to get the highest possible write speeds. Otherwise, it has to go through the ERASE->PROGRAM cycle to write, which is a lot slower than just PROGRAM if you've already performed the ERASE. CF cards too, although with UDMA7 & Trim, you don't necessarily need to do this as, like with SSDs, the camera can tell the card controller that it's deleted a file, and which LBAs, and so it can pre-ERASE those by itself.

 

[mikejkay]

mackguyver - what concerns me is the fact that SanDisk have grasped the measured write speed of 10.07 MB/s like a drowning man grasps a straw, totally ignoring the higher speeds achieved by supposedly lower spec cards. Not the response that I had expected given their reputation and fans such as yourself.

I agree with you about duff cards, the SanDisk card that I bought was a replacement for a "fake" Adata card that I bought and whci started behaving erraticly as soon as I started to use it. I should have known better having several times had my fingers burnt buying duff flash drived and memory cards. The Adata card was sufficiently expensive to make me think that it would be genuine.

Like you I am a bit paranoid about losing photographs which is why one of the selling points of the 5DIII for me was the ability to write files to two separate cards. Pity that this function is effectively crippled! Any way, I'm off to do a low level format on my SD UHS-1 cards and then try them in the 5DIII to see if this makes and difference. As you say, the proof of the pudding is in-camera performance not in a computer.

 

[Drizzt321]

Like you I am a bit paranoid about losing photographs which is why one of the selling points of the 5DIII for me was the ability to write files to two separate cards. Pity that this function is effectively crippled! Any way, I'm off to do a low level format on my SD UHS-1 cards and then try them in the 5DIII to see if this makes and difference. As you say, the proof of the pudding is in-camera performance not in a computer.

And yet again, it needs to be stated that it's not crippled. The functionality works 100%, and as designed based on the technology during the design.

There's nothing stopping you from taking the extra few seconds while it writes to the SD card before taking that 6th & 7th bracketed shots. Nothing is stopping you from that except yourself. The camera will let you take the last shots as soon as the buffer clears enough. Try it. I'm guessing the way you shoot the bracketed shots is via continuous shutter? Set it up, hold down the shutter, and at the end you'll have a pause, and then it'll take another shot (as soon as the buffer clears up).

 

[mikejkay]

I have to say that I do not agree about the SD slot being crippled. If the camera has been designed to use UDMA 7 CF cards it should have also been designed to accomodate UHS-1 SD cards. To the best of my knowledge the two specifications came out at about the same time. (Nov 2010 and May 2010 respectively). As Canon built the ability to save file to the two cards into the camera they should have made it a realistic proposition.

For anyone following this thread, and who is interested, I have formatted my UHS-1 SD cards and this makes no discernible difference to the time taken to the number of burst shots achievable or the time taken to clear the buffer (compared with the cards formatted in my laptop).

Not to worry, the 5DIII is still a brilliant camera. Pity I can't use it properly!

 

[Valvebounce]

Hi mikejkay.
Is that a windows 7 laptop? If so I believe that windows 7 does actually do a low level format by default, it was the first OS that I had no success recovering images with the software I was using after formatting a card, fortunately it was only a test as someone had brought this to my attention on another thread here. Try using quick format under XP if you have access to a machine running it then compare write speeds.
I know this won't change the issue you have with the write speed for burst but it may prove that it is worth doing the low level format. Or not!?

Cheers Graham.

I have to say that I do not agree about the SD slot being crippled. If the camera has been designed to use UDMA 7 CF cards it should have also been designed to accomodate UHS-1 SD cards. To the best of my knowledge the two specifications came out at about the same time. (Nov 2010 and May 2010 respectively). As Canon built the ability to save file to the two cards into the camera they should have made it a realistic proposition.

For anyone following this thread, and who is interested, I have formatted my UHS-1 SD cards and this makes no discernible difference to the time taken to the number of burst shots achievable or the time taken to clear the buffer (compared with the cards formatted in my laptop).

Not to worry, the 5DIII is still a brilliant camera. Pity I can't use it properly!