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

Michael Clark

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Nope, RAW (large file ) to CF Express and JPG (smaller) to SD. RAW is what about 4 times larger than JPG?
That's not the way it worked out with the 5D Mark III, 5D Mark IV, and 7D Mark II. Even when writing raw to the faster CF card and only JPEG to the slower SD card, the burst rate was impacted significantly compared to just writing raw to the CF card.
 

Michael Clark

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Because with the slower SD installed and the CFexpress also, max speed equals to that of the slower card. One will never get dual CFexpress bus speed. Thus one would have to remove the SD card for that CFexpress bus speed
One only has to turn it off. It can remain placed in the slot in the camera.
 

Michael Clark

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And why should this be the only possible rule? Why couldn't we imagine a scenario in which the SD card is only used when the CFexpress card is full? Or only as a backup, which doesn't have to be as fast as the main card. Or only to store jpeg?

Why limit our imagination to what we believe to be true?
Because of past experience with the 5D Mark III, 5D Mark IV, and 7D Mark II?
 

Michael Clark

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Never once in using the 5D3 for almost 8 years did I have issues or even think about having mixed slots. I truly love the problems of being a stills shooter over myriad of issues video people have. We win.
It makes a noticeable difference shooting sports with the 7D Mark II. The fastest UDMA-7 CF cards write at about 100 MB/s, the fastest UHS-I SD cards write at about 75 MB/s in it. The buffer gets full and slows down in fewer shots using the SD slot than the CF slot when saving raw.
 

Michael Clark

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Please explain: "(I'm still betting the 20FPS is going to be JPEG or HEIF only)"
JPEG and cr3 on the R is hardly different in size. While JPEG needs to be encoded, cr3 doesn't ...
.cr3 include a jpeg preview image that must be encoded, too.
 

Michael Clark

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There are UHS-II cards that can be read at 300MB/s. What drive can have data written to it at that speed? Then, nobody can post process images at 12 / 20 fps, so what does it matter anyway?
I don't think anyone is having a problem with the read speed of any card when talking about slots in cameras. They're talking about write speeds.
 

Michael Clark

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I don't know camera architecture, but you could potentially use a dual bus and dedicated memory to deal with the slower speed of the SD card. I doubt Canon is going to release a high end camera that degrades the performance to the lower value. I have used this approach with my 1dx II (granted with a CFast card) when I wasn't carrying a laptop on the trip. I didn't use the approach that often since I didn't want to buy a lot of CFast cards for backup:
  • Buy 2 128GB Cfexpress cards
  • Slot 1 (Cfexpress) 128GB Write RAW
  • Slot 2.(SD UHS II). 128GB Write high quality Jpeg for loading on my iPad for review
  • At the end of the day insert fresh SD "backup" card and use Image Copy to create a backup of the 128GB Cfexpress card. You couldn't even use one of the slower UHS I cards if you had time and didn't want to buy the more expensive cards.
Let us know if the CFExpress slot still transfers data at its native speed or if it is throttled to the same transfer speed as the SD card bus...
 

Michael Clark

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A deep buffer means lots and lots of RAM, which is both expensive and power hungry. I would guess that Canon reduced the amount of RAM to make it cheaper and last longer on a single charge. So the in-memory conversion of RAW to jpeg/heif would slow down things a lot. A way around this would be to generate the jpg/heif images from the RAW files after they are stored on the CFe. That wouldn't impact burst speed, but it would make people with card-failure fears a bit twitchy.
The camera already converts the raw data to jpeg when only saving to a raw format. There's always a jpeg preview image contained on the .cr2 or .cr3 file.
 

Michael Clark

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I've never experienced my 5D4 JPEGs being more than 25% of its corresponding RAW file's size, and the EOS R JPEGs I have are roughly 30% of their corresponding CR3 files. My JPEGS are always set to the highest quality setting. I don't see how you're getting JPEGs that are 75% or more of their corresponding RAW file.

Can anyone else confirm this? The only time I remember seeing JPEGs comparable in size to RAW is if the JPEG was created later in camera or in software on the computer.
I haven't seen that too but maybe you can tweak the picture styles to do that for you: High sharpening, high contrast, high color saturation that combined with highly detailed stuff - sand, crops, forests without sky might push jpeg to its limits of compression: Each pixel is different from the other and hence you have Imagesize ~ Number of pixels x 1 Byte.
Maybe in-camera HDR where three raw files are combined for one JPEG output image?
 

Michael Clark

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I write 400 mbps video to relatively inexpensive UHS-II cards all the time and I’ve never had a problem. Seems like a lot of fuss over nothing to me. If anything I would have preferred the ability to write directly to external SSDs but for some reason we can’t get that. Not sure why.
400 mbps is only 50 MB/s
 

Michael Clark

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Believe me, if there were no SD slot there would be people complaining over that too. I get that not everyone can be pleased, but there comes a point where the complaints are over wrought outrage for the sake of outrage. If I were to buy an R5 (huge if) I wouldn't be happy that I had to spend on a CFE card, but I wouldn't be crying on the forum about it page after page. It's the same mental hysteria that gives us the volumes and technical arguments over 1/2 stop of DR. 3,2,1...
Why is any opinion different from your own necessarily overwrought outrage and hysteria? Why can't it just be a differing opinion?

It's not going to ruin my life or anything, but I would prefer any R5 I might buy to have two CFExpress cards, just as I would have preferred my 5D Mark II, 7D Mark II, and 5D Mark IV to have had dual CF card slots or even dual UHS-II card slots instead of one faster CF card slot and one slower UHS-I slot that limits the write speeds of both slots to the slower bus speed of the UHS-I bus when simultaneously writing to both cards...
 

Michael Clark

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"Joe, which of your three lenses do you find yourself using most?"

I am using the 28-70 most of the time. I do not see a big difference in IQ between this and the two primes. Anyway, for all portrait work I use the 85. But for street or even landscape I am using the 28-70. I see myself using the 50 quite rarely these days (if the 28-70 had been the first lens released I would not have bought the 50)
Which is exactly why Canon released the 50mm first!
 

Michael Clark

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Absolutely Amazing! Specially since read speed on UHS II maxes out at 300 mb/sec and write speeds are always lower. Hypothetical max transfer speed on UHS II is 312 mb/sec. Your Canon R must have been sprinkled with some magic Pixy Dust!
400 mbs is only 50 MB/s. UHS II has a theoretical transfer speed of 312 MB/s, which is 2,496 mbps. There are eight bits (b) in one byte (B).
 
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Michael Clark

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yup, the max speed of the Sandisk Extreme Pro 64GB read speed is up to 300mb/s and write speed of 260mb/s which is the important one as that is what determines how fast the buffer fills up. Thats why I was asking what card you have as 400mb/s is incredibly fast for a UHSII card
400 mbps is slow for an UHS II card. That's only 50 MB/s.
 

CanonFanBoy

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Why is any opinion different from your own necessarily overwrought outrage and hysteria? Why can't it just be a differing opinion?

It's not going to ruin my life or anything, but I would prefer any R5 I might buy to have two CFExpress cards, just as I would have preferred my 5D Mark II, 7D Mark II, and 5D Mark IV to have had dual CF card slots or even dual UHS-II card slots instead of one faster CF card slot and one slower UHS-I slot that limits the write speeds of both slots to the slower bus speed of the UHS-I bus when simultaneously writing to both cards...
Calm down, dude. Overwrought are the people having continuous (post after post) hissy fits over something they already know isn't happening. Nothing wrong with wanting two matching slots. There is plenty wrong with continuously griping over something that IS NOT HAPPENING ALREADY. Children. Now please, carry on with your next 50 overwrought nightly posts.

BTW: I never said that any post that doesn't agree with my own is overwrought... that happens to be your own characterization. Project much?

Also, I too would prefer matching cards... BUT IT AIN'T HAPPENING. No sense crying over spilled milk.
 
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Michael Clark

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I don’t know why people are crazy about CFExpress cards price, they’re actually good deals, much faster cards with almost same price with ush-ii sd cards. Sandisk uhs ii 128gb is ~$200, CFExpress 128gb $200-$250.
Because they are comparing the price of CFExpress cards to the price of non UHS SD cards that only write at 30 MB/s or less instead of the ones that can write close to 300 MB/s.
 

Michael Clark

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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.
'Ya got a link to where I can order a 45MP 1D X Mark III?