SD Cards on EOS 5D Mark III

The SD card slot of EOS 5D Mark III doesn't support high speed SD cards(UHS-1). It is said that the maximum speed is 133x which is awfully slow in burst mode. Has this been corrected in any firmware ?
Thanks
Jai.

I have the 5D3 and 5D4 bodies both with the latest firmware. Here is data from a test I just completed:

Both cameras set to RAW, manual exposure, 1/5000, lens wide open, lens set to MF, lens cap on

5D3 w/Lexar Professional 133x card 15 shots until buffer fills, 26 seconds for buffer light to go out
5D3 w/Lexar Professional 633x UHS1 card 15 shots, 16 seconds

5D4 w/Lexar Professional 133x card 20 shots, 38 seconds
5D4 w/Lexar Professional 633x UHS1 card 24 shots, 13 seconds

I performed all the above tests twice and numbers were virtually identical.

In actual use when shooting a couple series of RAW bursts my 5D3 can go into slow shooting mode from time to time. I've never had this happen when using the 5D4. It just keeps on shooting. That's not to say if I (obviously) shot a long enough burst it wouldn't stop. That's just not real world shooting for my uses. Hope this helps.

J R Mohan wrote in post #18546194
The SD card slot of EOS 5D Mark III doesn't support high speed SD cards(UHS-1). It is said that the maximum speed is 133x which is awfully slow in burst mode. Has this been corrected in any firmware ?
Thanks
Jai.

When Canon released the Eos 5D MK III they used an outdated hardware interface for the SD card. There is no firmware fix in this instance. The CF interface is what has the speed in this case.

Regards,

110yd

Thanks for the reply. However it seems strange when the usage of CF cards is on the decline and SD cards getting more popular. Also SD cards are more affordable in comparison to CF cards.
Jai.

As mentioned above, FW can't fix the hardware interface limitation. To support UHS-I, the interface clock needs to operate at 208MHz, giving the UHS-I interface speed of 104MB/s. In 5DIII, the interface is operating at 50MHz, giving a interface limit of 25MB/s. Having that said, the burst depth for still is more buffer size depended than card speed dependent. Sure with a faster card, buffer clearing is faster and will give you a few more frame of RAW, but I can't imagine the difference is too huge. For video, 5DIII will only do 1080P, so all you need is speed class 10. 25MB/s interface will do it just fine. It still sucks why Canon decided to cripple the SD interface.

5DIII isn't exactly new too.

Thanks for the information. 5D markiii SD slot speed is a big disappointment.
Jai.

eelnoraa wrote in post #18547630
5DIII isn't exactly new too.

I agree its not new. But the way canon always gimps its cameras on release is not new either.
The 5div could have had xqd and a UHS-II. Instead is has cf card and UHS-1.

I do agree Canon cripple things intentionally is a bad habit. But I can understand why 5D4 doesn't have XQD or UHS-II.

First XQD, Canon was never behind the development of XQD. Canon is one of the driver for CFast format. Now, technically, XQD and CFast is really exactly the same with different packaging. Both are SATA protocol interface. So the conclusion is really about format war. In this case, a losing format war from the past. As far as I know, there is a new format coming out, supposed to be the agreement between the XQD and CFast crowd. Let's wait for it.

2nd reason is cost. Given what 5D4 needs, there is nothing XQD/CFast USH-II can do but CF or USH-I can't do. What is the reason to go for a much more expansive format? As an consumer, I actually prefer an existing interface as long as it does everything the body is capable of. Now I think having UHS-II interface still make sense because it is backward compatible with USH-I. XQD/CFast, I just don't see why I want to ditch all my CF for these "will be short live" and expansive format.

CFast and XQD were introduced mainly for higher frame rate video. The Arri Alexa and Amira, Blackmagic URSA, Canon XC10, Hasselblad H6D-100C, and Atmos Ninja and Shoguns are cameras/video devices that use CFast. So there are enough brands in the cinema market that support the format for it to not be short lived. Now, the CompactFlash Association has conceived a new standard called CFexpress (that has a XQD form-factor). As newer camera models come out, they may start incorporating it if its two PCIe lanes are required. Film studios are not going to ditch CFast on their current Arri, Blackmagic, or Canon cameras.

davesrose wrote in post #18552105
CFast and XQD were introduced mainly for higher frame rate video. The Arri Alexa and Amira, Blackmagic URSA, Canon XC10, Hasselblad H6D-100C, and Atmos Ninja and Shoguns are cameras/video devices that use CFast. So there are enough brands in the cinema market that support the format for it to not be short lived. Now, the CompactFlash Association has conceived a new standard called CFexpress (that has a XQD form-factor). As newer camera models come out, they may start incorporating it if its two PCIe lanes are required. Film studios are not going to ditch CFast on their current Arri, Blackmagic, or Canon cameras.

CFExpress is exactly what I was referring to. It is also supposed to be backward compatible with the current XQD slot. But the adaptation on the consumer segment will be very slow, just like CFast and XQD.

eelnoraa wrote in post #18547628
It still sucks why Canon decided to cripple the SD interface.

It's the fault of Mrs. Tanaka. In case you haven't heard about this lady, she cleans the rest rooms at the Canon Headquaters but, she moonlights as the head of the Canon R&D and marketing departments.

In fact, Canon was going to name the 6D Mark II, "6D Tanaka" in honor of the things that camera is lacking. They lost out but, could have named the M50. The "M Tanaka".

Wait for more wonderful retro products that Canon and Mrs. Tanaka plan to foster on the camera buying public