The 5D Mark III & SD Memory Cards

[revup67]

Sorry - this is *not* new information.  In Canon's defense this is all explicitly stated on page 117 of the owner's manual.  If you are concerned about burst mode then leave camera on Standard or Auto Switch Card.  The manual states:  "When Rec. separately is set, the maximum burst will decrease greatly. (See pg 121)".  Pg 121 further explains on the matrix the burst rates and also states: "The Maximum burst rate applies to High Speed Continuous Shooting", it then extrapolates that it is referring to UDM7.  It may seem obvious then since the SD cads (if engaged in the two other record modes modes) would have to be the lowest common denominator.  On page 32 the manual also states the camera does not comply with UHS standards although these cards can be used.

Now a good work around to this if in the field and you need the backup feature but also the fastest burst mode on a UDMA7 CF card is set the camera to record only on the CF card (Standard Mode). Be sure the CF is the card chosen to record (under Record/Play menu) as well.  Now you can copy your images to the SD card by pressing Menu.  Choose Menu section 3, sub menu 1 and select "Image Copy".  Here you can define your Source (the CF card) and the freespace on Card 2 (SD card)  there you can copy all your CF images to an SD card without losing burst mode speed and still have your backup.

[tt]

There's no need to actually remove the card. Just set the camera to auto-switch. You get full performance while it's using compact flash.

I know that's the theory, but have you tested this personally?  Thanks!

With both cards in, set to autoswitch, set to record to the CF card, I got >24 RAW pictures in a burst till it went to the slower frames per second speed. With just a CF card in the camera, there wasn't a difference.
Am I missing something?

Sounds like Jeff's talking about recording to both cards at the same time - which on p117 or so in the manual clearly states will "decrease greatly" the maximum burst.

The camera defaults to the slowest card - but only if you have that card select to record onto, or you're recording to both cards.

To be more accurate with the headline:

Why you can leave an SD card in your Canon 5D Mark III, but if you care about speed, don't record to it if you can, and be aware that recording to both cards simultaneously decreases greatly your maximum burst available

Having a SD card in the camera doesn't make it slower - selecting to use it does. I'd recommend having one in their as a fall back in case your CF card runs out of space. However - if you only have a CF card in there, there's no chance of having the issue (eg accidental setting change form autoswitch to rec separately/to multiple)

[neuroanatomist]

Thanks for clarifying, TrumpetPower! and tt...

[FunkyCamera]

Nobody needs to shoot that fast anyway it's a waste. Nikon only leads in areas that don't matter, I'm sticking with my Canon. 

[Razor2012]

Nobody needs to shoot that fast anyway it's a waste. Nikon only leads in areas that don't matter, I'm sticking with my Canon. 

It's only res & DR anyways.   

[RGomezPhotos]

It may be in the manual, but this is still not good.  If you have two 600X cards in the camera, I wouldn't think it should be that fast to write to both cards if they are the exact same data, but it shouldn't be at 133X either.  I seriously hope Canon can resolve this though I doubt it.

[Razor2012]

It may be in the manual, but this is still not good.  If you have two 600X cards in the camera, I wouldn't think it should be that fast to write to both cards if they are the exact same data, but it shouldn't be at 133X either.  I seriously hope Canon can resolve this though I doubt it.

Probably card limitations, CF's - 150 MB/s compared to SDHC's - 95 MB/s.

[WillShootPhotos]

Someone asked about some testing - well - here is what I've found from testing on both the 5D3 and the 1D4:

Short version:
5D3 - RAW - UDMA 7 - "rollover" to SD after CF is full:
26 frames till full with the buffer emtying in just over 3 seconds

1D4 - RAW - Firmware 1.1.1 - UDMA 7 - rollover to SD after CF is full:
31 frames till full with the buffer emptying in just over 6 seconds

I just verified that it makes no difference if I pull the SD card - the writing to the CF is the same.

I really wish the guy who wrote the original blog post that started this had clarified his title - I think it should have been:

"Why you should not put write to an SD card in your Canon 5D Mark III (if youcare about speed)"

If you want my testing gory details - here is my blog post about it:
http://blog.willshootphotography.com/2012/06/udma-7-cf-card-performance-on-canon-5d-mark-iii-and-1d-mark-iv-soooo-worth-it.html

I'll be candid and say I don't have a problem with the SD not supporting the superfast SD protocol - primarily because I'll always just use it as a rollover, not as a primary "write to" card type. I know that CF is faster than SD and that is what works for me. I'm really glad that Canon put dual SD in 1DX - it never made much sense to me to *not* have two of the same card reader in the camera other than for space restrictions... and it doesn't take up *that* much space...

Happy motoring!

- Will

[Razor2012]

Someone asked about some testing - well - here is what I've found from testing on both the 5D3 and the 1D4:

Short version:
5D3 - RAW - UDMA 7 - "rollover" to SD after CF is full:
26 frames till full with the buffer emtying in just over 3 seconds

1D4 - RAW - Firmware 1.1.1 - UDMA 7 - rollover to SD after CF is full:
31 frames till full with the buffer emptying in just over 6 seconds

I just verified that it makes no difference if I pull the SD card - the writing to the CF is the same.

I really wish the guy who wrote the original blog post that started this had clarified his title - I think it should have been:

"Why you should not put write to an SD card in your Canon 5D Mark III (if youcare about speed)"

If you want my testing gory details - here is my blog post about it:
http://blog.willshootphotography.com/2012/06/udma-7-cf-card-performance-on-canon-5d-mark-iii-and-1d-mark-iv-soooo-worth-it.html

I'll be candid and say I don't have a problem with the SD not supporting the superfast SD protocol - primarily because I'll always just use it as a rollover, not as a primary "write to" card type. I know that CF is faster than SD and that is what works for me. I'm really glad that Canon put dual SD in 1DX - it never made much sense to me to *not* have two of the same card reader in the camera other than for space restrictions... and it doesn't take up *that* much space...

Happy motoring!

- Will

Dual CF. 

[Drizzt321]

It may be in the manual, but this is still not good.  If you have two 600X cards in the camera, I wouldn't think it should be that fast to write to both cards if they are the exact same data, but it shouldn't be at 133X either.  I seriously hope Canon can resolve this though I doubt it.

Probably card limitations, CF's - 150 MB/s compared to SDHC's - 95 MB/s.

Actually, 133x is ~20MByte/s according to http://en.wikipedia.org/wiki/Secure_Digital. You need SDXC to go up 50+ MByte/s, with UHS-I needed to go above 90+ MByte/sec transfer speeds. So, if you have a 600x CF card (I think UDMA6 can do that, maybe requires UDMA7 which 5d3 supports) and a 600x SD UHS-I card, you'll get 200x (30MByte/sec) speeds at most. In the real world, quite a bit less (see Rob Galbraith's test page, search for 600x and find an SDHC card).

[CanineCandidsByL]

Unfortunately my own theory about why the SD is crippled is more annoying. Because SD can be cheaper and nearly as fast as CF, which would move the 5D3 closer to the 1dx than canon marketing wants.

No proof, but certainly reaonable based on other behavior. Not that I have minded it once I got over the initial shock when the manual first became available. The rollover prevents you your photos from stopping completly while you find the right moment to swap the CF.

However, putting in a new CF isn't the end of it. You have to manuall switch the camera back to recording on the CF or it stays on the SD until its full. That another 10 to 20 seconds after already being slow and swapping a card until you get back to the job.

I think the major disppointment was that you couldn't do jpg to SD and RAW to CF without the performance hit.

[Drizzt321]

Unfortunately my own theory about why the SD is crippled is more annoying. Because SD can be cheaper and nearly as fast as CF, which would move the 5D3 closer to the 1dx than canon marketing wants.

No proof, but certainly reaonable based on other behavior. Not that I have minded it once I got over the initial shock when the manual first became available. The rollover prevents you your photos from stopping completly while you find the right moment to swap the CF.

However, putting in a new CF isn't the end of it. You have to manuall switch the camera back to recording on the CF or it stays on the SD until its full. That another 10 to 20 seconds after already being slow and swapping a card until you get back to the job.

I think the major disppointment was that you couldn't do jpg to SD and RAW to CF without the performance hit.

I haven't tested to find out, but I imagine S2 or S3 JPEG would probably be able to keep up, or nearly so. Significantly less data to write out than even a Large JPEG. I've heard of some people using the SD slot for an EyeFi card for JPEGs in the studio or on location but not needing a super burst rate. If you're strobe recycle rate is > 0.5s, or even > 1s, then even with an EyeFi card you can probably shoot JPEG out to it and unless you're shooting 100+ photos in a couple of minutes, it probably should be alright since it has the built in flash as a buffer for the very slow WiFi built in.

[neuroanatomist]

Unfortunately my own theory about why the SD is crippled is more annoying. Because SD can be cheaper and nearly as fast as CF, which would move the 5D3 closer to the 1dx than canon marketing wants.

No proof, but certainly reaonable based on other behavior.

Wait, wait...  You seem to be suggesting that Canon would intentionally cripple a camera model?!?   

[Drizzt321]

Unfortunately my own theory about why the SD is crippled is more annoying. Because SD can be cheaper and nearly as fast as CF, which would move the 5D3 closer to the 1dx than canon marketing wants.

No proof, but certainly reaonable based on other behavior.

Wait, wait...  You seem to be suggesting that Canon would intentionally cripple a camera model?!?   

Blasphemer! Companies don't ever cripple their lower end products to protect profits on a more expensive, lower volume, higher margin product! Never! They always provide the best possible product at a given price point. It only makes sense.

[briansquibb]

Unfortunately my own theory about why the SD is crippled is more annoying. Because SD can be cheaper and nearly as fast as CF, which would move the 5D3 closer to the 1dx than canon marketing wants.

No proof, but certainly reaonable based on other behavior.

Wait, wait...  You seem to be suggesting that Canon would intentionally cripple a camera model?!?   

The 5DIII and the 1D4 share the same unit. Personally I only have the SD for overflow should the CF fill up. I soon realise that I have switched. On the 1DS3 at 5fps it is not such a problem as the SD speed doesn't slow it down so much

Why do people think that Canon cripple a model rather than not give it all the bells and whistles? I suspect in this case they have filtered down the unit from the 1D4. If it was good enough for the 1D4 users it should be good enough for 5DIII users. More a case of looking for minor improvements that could have been incorporated and turning them into a major issue

Just remember the 5DIII arrangement is better than the D800