The Canon EOS R5 will have an SD & CFExpress slot [CR2]

jam05

EOS RP
Mar 12, 2019
201
102
why is a UHS-II SD slot suddenly useless?
It's useless if you've purchased a CFexpress card for write speeds at 1gbs. The SD slot is 640mbs tops. Tortoise speed. The camera will always write at the lowest card slot speed when two different cards are used. In essence making the second slower SD slot useless, when using the CFexpress slot.
 

jam05

EOS RP
Mar 12, 2019
201
102
Yes the second SD UHSII slot is in essence "useless" when using a CFexpress card for it's 1GBS write speed. The UHS II cards at tortoise write speeds would not be the cards of choice for those with desire to optimize the cameras image processing performance. It's simple.
 

jam05

EOS RP
Mar 12, 2019
201
102
Wait for the R1, then.

No offense to Mr. Toes, or any other poster, but this thread is bananas. I can't imagine a less controversial Canon decision than this; every 5D since the mark II has had mismatched slots. It's a feature of the line by now. Deal with it, or buy something else.
And forever has been the complaint of throttled down write speed from those knowledgeable. Of course there were many that never knew and assumed that the 5D would be writing at two speeds.
 

jam05

EOS RP
Mar 12, 2019
201
102
I looked up the specs, UHS-II can theoretically go up to 312 MB/s (half duplex, i.e. read or write).
Yes in 2020 it's " tortoise" speed in comparison to a CFexpress card at 1GBS per channel. The CFexpress slot would be throttled down to the slower SD slot.
 

SecureGSM

2 x 5D IV
Feb 26, 2017
2,288
1,129
And forever has been the complaint of throttled down write speed from those knowledgeable. Of course there were many that never knew and assumed that the 5D would be writing at two speeds.
Yes in 2020 it's " tortoise" speed in comparison to a CFexpress card at 1GBS per channel. The CFexpress slot would be throttled down to the slower SD slot.
Yes the second SD UHSII slot is in essence "useless" when using a CFexpress card for it's 1GBS write speed. The UHS II cards at tortoise write speeds would not be the cards of choice for those with desire to optimize the cameras image processing performance. It's simple.
yeah, SONY got it right in a7R IV !!! A stunning write to card performance. with a second memory card being SD UHS II.. oh, wait.... :D

"... A couple of big things have changed with the Sony A7r IV compared to the previous model. The biggest is the addition of a UHS-II memory card in Slot 2 for incredibly fast memory card speeds when shooting with a dual memory card setup.

It also looks like Sony has upgraded the UHS-II hardware as it’s now one of the fastest mirrorless UHS-II cameras (A.M.: but only until R5 did hit the market later in 2020)... with performance very similar to the XQD cards found in the Nikon Z6/Z7...."

 

BillB

EOS R
May 11, 2017
1,393
659
And forever has been the complaint of throttled down write speed from those knowledgeable. Of course there were many that never knew and assumed that the 5D would be writing at two speeds.
And there were those who could work with the slower write speed.
 

docsmith

EOS R
Sep 17, 2010
934
351
unlike the 1DX Mark III that can shoot at 20 fps with a mechanicall shutter - the R5 cannot.

people seem to be keying on the 20 fps when in all practicality, the 12 fps is most likely going to be used most often because of the mechanical shutter.

I don't notice any real problems on the M6 II and that's with 16 fps and 32.5MP. around the same as 12fps and 45mp.

IMO, this issue is overblown.

Granted you have two dissimilar cards and the nonsense dealing with that - but Canon is going to leave some stuff off for the R1. You can't expect everything you dream of on the R5 when Canon has to turn around and try to convince you to get an R1 in a year's time.
A minor detail, but I believe you mean 14 fps on the M6 II.

But, during this discussion I have thought the same thing, that, while lower, the M6 II is ballpark to the same throughput we are talking here. So, I tested this yesterday and just to confirm, a second time just now. At least my M6 II, the buffer fills up at EDIT (just checked spreadsheet before closing it) 1.85 seconds. The frame rate during that time was 12.5 fps yesterday and 13 fps today (rated at 14, but I was above ISO 100, so that may explain it). After that 1.85 second burst, the M6 II then dropped to an average of 2.1 fps for another 18 seconds that I tested. I've actually just ordered a UHS-II card for my M6 II (a benefit of this thread, I hadn't even thought about it and have been using a 95 MB/sec Sandisk Extreme Pro UHS 1 card I have). But, file size was 32.9 MB, so the throughput after the buffer was filled was 69.1 MB/sec, which is about the read speed of the Sandisk.

Applying that to a UHS-II card, it has been observed that the real write speed of the very best cards is 180 MB/sec in the EOS-R.

So, based on science, you know, working, I would assume that with my M6 II could do ~5.5 fps after the buffer fills if I have a UHS II card. Apply this to a Canon camera where file sizes vary with ISO but tend to range from the 1 to 1.5x the resolution, a 45 MP camera would likely have ~45 MB files at low ISO and ~60 MB files at high ISO. So, with UHS II you are looking at 3 - 4 fps with UHS II after the buffer is filled.

So, next, I am waiting to hear how large the buffer is on the R5. If say 10 seconds, I am probably good and do not consider it an issue. If like the M6 II and 1.85 secs...I consider this to be an issue. (EDIT-just checked my 5D4, 2.4 seconds to fill buffer). Point is, if the buffer is as small as other cameras, I will be turning off the SD card any time I want high fps, negating the benefit of a second card slot.

Oh, and for those of you citing Sony....this is one of the top gripes I hear from Sony users, after the buffer fills it takes FOREVER to write all the data to the card.

So, "overblown"...sure, for landscape/portrait photographers. Wildlife/sport photographers who want more than 20MP resolution, I think that is who is evaluating this a bit more critically.
 
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Starting out EOS R

EOS R5 - RF24-105mm F4L, RF70-200mm f2.8L
Feb 13, 2020
272
302
There's a list of female celebrities who, I suspect, disagree with your description of the service.
Bear in mind too that SSD memory is "great", but it can (and does occasionally) fail (albeit it is much more reliable than spinning discs).

So, what do you do with the camera if the built in memory fails? It will be repairable of course, but not great for a working pro. You could make it easily replaceable.... if it is easily replaceable, why not just have a removable disk....and hey presto you're back to a card :D
Exactly. I think Canon will retain the removable medium for a while as it certainly has the benefits you describe. However longer term, I can see the internal SSD memory option being very attractive if the transferring of images to cloud storage is seamless and the robustness of the memory improves. Again, similar to smart phones, tablets etc, Ive never had a memory failure and the back up functions are seamless so even if it did fail, things are safe. I think this will be a way off though and it's likely that a starting point would be a combination of both internal and removable. Who knows??
 
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uri.raz

EOS RP
Jan 5, 2016
213
134
It's useless if you've purchased a CFexpress card for write speeds at 1gbs. The SD slot is 640mbs tops. Tortoise speed. The camera will always write at the lowest card slot speed when two different cards are used. In essence making the second slower SD slot useless, when using the CFexpress slot.
A) If its that important to you, either use one slot, or buy the EOS 1D X for its dual CFExpress slots,.

B) Until literally last month, the best you could get was dual UHS-II (312 MB/s) in Sony land, announced under 9 months ago. Yet, people are already bi***ing about it not becoming a standard.
 

Quarkcharmed

EOS 5DMkIV
Feb 14, 2018
1,175
1,031
Australia
www.michaelborisenko.com
Exactly. I think Canon will retain the removable medium for a while as it certainly has the benefits you describe. However longer term, I can see the internal SSD memory option being very attractive if the transferring of images to cloud storage is seamless and the robustness of the memory improves. Again, similar to smart phones, tablets etc, Ive never had a memory failure and the back up functions are seamless so even if it did fail, things are safe. I think this will be a way off though and it's likely that a starting point would be a combination of both internal and removable. Who knows??
In the cameras of this grade, the cloud storage will never be a primary storage. Maybe in the remote future where there's stable internet connection everywhere? But now... you can easily have 128G of data after a photoshoot. Imagine uploading it to the cloud from a remote area with poor reception and waiting until upload has finished until you can resume shooting. Several hours of uploading and you have no battery power because your camera must be on during the process. Also the cost of WiFi/4G/5G may be drastically different between your CBD and remote towns or countries. The cloud is great as a backup storage but not as a primary working storage.

Internal in-camera storage has already been used in some Canon camcorders (HF10 for example - but it had a card slot too). The disadvantage is that it's a weak link, if it fails the whole camera fails, you can't expand and upgrade it and it also increases the cost of the camera.
 

jam05

EOS RP
Mar 12, 2019
201
102
Would gladly trade in ditch all the old slow SD cards for
SanDisk 128 Extreme Pro CFexpress Card Ty[e B
 

peters

EOS RP
Dec 25, 2017
299
298
But people who claim stills are 20FPS *continuously* are not doing stills. Thats a video ...
Sports and some animal photographers may disagree.
But basically you are correct, its not much of an issue for photographers.

I think I wokuld have preferred 2 cfe slots, so I dont need so many different cards... but being able to use cheap SD cards is also a nice feature. :)
 
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neurorx

EOS 90D
May 12, 2015
118
60
unlike the 1DX Mark III that can shoot at 20 fps with a mechanicall shutter - the R5 cannot.

people seem to be keying on the 20 fps when in all practicality, the 12 fps is most likely going to be used most often because of the mechanical shutter.

I don't notice any real problems on the M6 II and that's with 16 fps and 32.5MP. around the same as 12fps and 45mp.

IMO, this issue is overblown.

Granted you have two dissimilar cards and the nonsense dealing with that - but Canon is going to leave some stuff off for the R1. You can't expect everything you dream of on the R5 when Canon has to turn around and try to convince you to get an R1 in a year's time.
Why would mechanical shutter be used more than an electronic one? Isn’t mechanical largely for flash photography or in old school lighting?