UHS-I or UHS-II with 90D?

AlanF

Canon 5DSR II
Aug 16, 2012
5,802
3,283
As a stills shooter, will I miss out by not using a UHS-II card for the 90D? Downloading to the computer will not be speeded up for me as the camera has only a USB 2.0 connector and I don't want to use a fast external card reader, and I doubt if I'll be downloading more than 32 GB at any one time anyway. Will the slower write speed of a Sandisk Extreme Pro, for example, slow down the bursts?
 

koenkooi

EOS 7D MK II
Feb 25, 2015
514
304
From the early hands-on reviews it sounds like the 90D has a bigger buffer than the M6II, so you're less bound by card speed in bursts. The big caveat with UHS-I and UHS-II is that using a type II card in a type I slot tends to have lower performance than a type I card in a type I slot.
Your use case shouldn't have any weird slowdowns due to type I card in type II slot, that's perfectly fine.

In my RP the difference between I and II were obvious, with a fast UHS-II card it keeps shooting at max fps (which isn't a lot), with a UHS-I card it would slow down after a few seconds when the buffer filled up.

I personally went with UHS-II cards for all my cameras since I use a fast external reader which made downloading more than twice as fast compared to UHS-I cards. In your case, how often have you outrun the buffer in the 90D in the past few days?
 
  • Like
Reactions: AlanF

bhf3737

---
Sep 9, 2015
479
518
Calgary, Canada
www.flickr.com
The site Camera Memory Speed has result of speed test for several UHS-I and II cards for many cameras. Of course 90D is not there yet. Apparently the average write speed differs depend on the implementation by manufacturers. Canon's UHS-II implementation tops around 180MB/S and about 75 MB/S for UHS-I cards. In the tested card list, there are several Sandisk Extreme Pro cards with various speed ratings. Given the SD cards getting cheaper and cheaper, for me, using UHS-II cards with twice write speed compared to UHS-I seems to be a good decision.
 
  • Like
Reactions: AlanF

AlanF

Canon 5DSR II
Aug 16, 2012
5,802
3,283
Thanks for your input. The price difference on Amazon UK for Sandisk Extreme Pro UHS-1 and -II cards is a factor of 4. Eg 64Gb 170MB/s is £24, and 300MB/s is £100. (I have a couple of virtually unused Extreme Pros in the 2nd slots in my 5DIV and 5DSR :).) So, it's whether it will make a difference.
 

AlanF

Canon 5DSR II
Aug 16, 2012
5,802
3,283
I bought a 32GB Sandisk 2000x 300/s UHS-II Extreme Pro (cost £52) and compared it with my new 64GB Sandisk 170/s UHS-I Extreme Pro (cost £22) on my 90D. Under the same conditions, I let it go for the full burst and then another 5 shots. With the UHS-I the burst was 22 full RAW and then about a shot every 0.5s, and then 15s to write fully to disk. For the UHS-II, it was basically the same a burst of 23 shots, then a similar speed of 5 shots in about 2s , and 15s again to write full to disk. If I try continuous shooting, there is the burst of 22 shots, 7-8 slow ones in about 3s, then a series of short bursts with pauses in between. Importantly, the camera keeps working with these short bursts while the writing to disk continues and doesn't seize up - as space in the memory becomes available, the camera will fire.

Do I think the the UHS-II is worth the extra cost? Not for the way I use the camera, but others might think so.
 
Last edited:

AlanF

Canon 5DSR II
Aug 16, 2012
5,802
3,283
I checked that the SanDisk Extreme Pro UHS-II does write files at >230 Mb/s and the UHS-I at >85 Mb/s. So, the 90D appears to be throttling the writing to the card to an estimated 60Mb/s.
I found a thread - https://www.dpreview.com/forums/thread/4432716?page=3 where it seems there isn't much advantage in using a fast UHS-II card with the 90D or M6 II.

I followed the recommended procedure in the dpr thread https://www.dpreview.com/forums/post/63202460 to measure the write speed.
Low format card, set to 1000/s iso 100 in Manual with body cap on. Shoot RAW files for 1 minute and time the complete writing to card. DLO, peripheral illumination etc etc etc were all turned off.

1. 64Gb SandDisk Extreme Pro UHS-I gave 246 19.8Mb files, 10 s clearance, 4.87Gb = 70 Mb/s
2. 32Gb SandDisk Extreme Pro UHS-II gave 259 19.7Mb files, 10 s clearance, 5.10Gb = 73Mb/s

So pretty much a waste of time getting the UHS-II cards for stills shooting. If you take them out of the camera and use a UHS-II card reader to download to your computer, it will save a few seconds.
 
Last edited:
  • Like
Reactions: clbayley

Keith_Reeder

No apologies for not suffering fools gladly...
Feb 8, 2014
823
273
59
Blyth, NE England
I had the same dilemma with the M6 Mk II, Alan - I decided on a 128gb "fast" UHS-1 card, because I never max out on a burst, and the UHS-1 card is plenty fast for how I actually shoot.

Much, cheaper, of course - and I really appreciate the capacity.

 

Mt Spokane Photography

I post too Much on Here!!
Mar 25, 2011
15,544
768
I purchase UHS II cards for my EOS R, its the future, so I spend a few dollars more and get them. I have two now, a Lexar 128 GB 1000X UHS II is currently in my camera. It cost me $50 last Christmas, they will probably cost less this holiday season. Its not the fastest card, but it is more than what I need.
 

Keith_Reeder

No apologies for not suffering fools gladly...
Feb 8, 2014
823
273
59
Blyth, NE England
Unfortunately, the price difference between UHS-I and UHS-II in the UK is really off-putting - right into "if you don't need it, don't do it..." territory.

Hmmm... Having said that:


OK, just ordered it.
 
Last edited:

AlanF

Canon 5DSR II
Aug 16, 2012
5,802
3,283
Unfortunately, the price difference between UHS-I and UHS-II in the UK is really off-putting - right into "if you don't need it, don't do it..." territory.

Hmmm... Having said that:


OK, just ordered it.
The Lexar 1000x UHS-II reads and writes slower than the SanDisk extreme pro 170mb/s.