When I initially bought my X-T1 last year, I had not planned on buying the new, super-fast UHS-II cards for it since I had not planned to sustained 8fps very often, so I thought my Sandisk Extreme Pro was good enough.
For my creative shooting, it is just fine, but when I shoot soccer, cross country and awards ceremonies, I often shoot in repeated bursts of 3 frames with only a second or two between bursts (JPEG+RAW to be able to make the best corrections), and the Sandisk UHS-I card doesn’t clear the buffer fast enough. That’s why I got the latest Lexar 2000x UHS-II card which everyone seems to like.
Below are two tests:
- The first test was to determine when it would fill the buffer and how long it would take to empty the buffer.
- The second test was to pit different cameras against each other in repeated short burst situations.
So did it the UHS-II perform noticeably faster than the UHS-I? Yes it did.
- The UHS-II consistently emptied a full buffer 6 seconds faster (as Captain Kirk would say, that is an eternity in photography seconds).
- I consistently got more shots in the repeated short burst stress test.
Did it perform as well as my Canon 7D + SanDisk Extreme 60MB/s read/write Compact Flash card? Yes (and no).
- The old CF card isn’t as fast (but that’s what I use in my Canon 7D which rarely lags shooting sports)
- Although the numbers show the Fuji+UHS-II card performed better, the Canon would consistently shoot at least one shot after the buffer was full, but the Fuji would sometimes lag. This can impact your confidence as a sports or fast-moving event photographer.
Cards in the tests:
- 32GB, Sandisk Extreme Pro, SDHC UHS-I in Fuji X-T1
- 32GB, Lexar 2000x, SDHC UHS-II in Fuji X-T1
- 32GB, old SanDisk Extreme CF 60MB/s in Canon 7D
JPEGS were set to Fine or Large. RAW was also set to Large.
The subject was my living room. Single focus. 8fps.
Important note: Ignore the exact number of photos taken and compare the relative amounts. The number of photos changes based on what you shoot. More detail creates bigger files, but the relative difference in the number of photos taken and time it takes to purge is what is important.
And, yes, I formatted the card after every test rather than just deleting all the photos.
Full buffer purge test results:
before full buffer
Buffer purge time*
|Sandisk Extreme Pro||90 MB/s||24**
|Lexar 2000x||260 MB/s||25***
|SanDisk Extreme Compact Flash
in Canon 7D
*Time to empty buffer starting from initial shutter release
**Includes one photo after initial stagger
***includes 2 photos after initial stagger (I tried many times to release my finger after one stagger, but it kept capturing 2 – I guess my reflexes are too slow)
Time to full buffer shooting JPEGs only
For both SD cards was 47 photos (that’s almost 6 seconds), then it slows down to about 3-5fps. These 47 JPEGs finally cleared the buffer in about 4 seconds for the Sandisk UHS-I and in about 2 seconds for the Lexar UHS-II. At 278-280MB, that’s about 28MB/s and 35MB/s. Why slower? Multiple smaller files (JPEGs) write slower than multiple large files (like RAW files).
But for the old CF card in the 7D, it was able to shoot 200 JPEG onlys until it started to stutter. Yes, 200! This was at 8fps. If I was shooting continuous focus (at about 3-5fps), this could have been until the card was full.
Why aren’t these measurements near the advertised speeds?
Because my test includes the complication of the camera writing to internal memory, reading from internal memory and then writing to the card. Manufacturers don’t know how your hardware will perform — they can only advertise what their product will do without complications.
Repeated short burst stress test results:
The more interesting test I did was to simulate real-world repeated short burst shooting. I did this by using a stopwatch and pressing down on the shutter for 1 sec followed by a 1 sec pause, then repeating until I did 5 bursts. Then I did the same with 10 bursts.
|SanDisk Extreme Pro||29||
|SanDisk Extreme Compact Flash in Canon 7D||25||
These tests were done on a static image, so results will very likely vary for moving subjects and continuous focus.
Also, what picture you got isn’t reflected in numbers. After the buffer was full, the 7D would still shoot immediately after the shutter button was pressed, but maybe for only one shot, but the Fuji wouldn’t always shoot something immediately. The result is that you may have more shots with the Fuji, but THE shot you see may not be captured depending on how you shoot.
I cheated to get the burst in the featured image. I used some online clipart (lowered about 50% to match the low ambient lighting) and shot so the background was out of focus.