Camera Labs

Let's begin with the backstory. I found myself needing more memory cards, and started comparing prices online. I noticed that Transcend memory is a LOT cheaper than Sandisk, and offers more bang for the buck. User reports online seemed pretty positive, so I went for it.

All tests are conducted with a Conceptronic all-in-one reader, connected via USB 2.0 (highspeed). Benchmarking program is CrystalDiskMark, set to 2 tests of 50 MB size

Sandisk 8 GB UltraII CF 30mb/s

Sequential Read : 18.062 MB/s
Sequential Write : 16.500 MB/s
Random Read 512KB : 18.595 MB/s
Random Write 512KB : 2.868 MB/s
Random Read 4KB (QD=1) : 4.630 MB/s [ 1130.3 IOPS]
Random Write 4KB (QD=1) : 1.193 MB/s [ 291.3 IOPS]
Random Read 4KB (QD=32) : 4.222 MB/s [ 1030.8 IOPS]
Random Write 4KB (QD=32) : 1.234 MB/s [ 301.2 IOPS]

Transcend 4 GB 133x CF (Outspecced by the Sandisk to be fair)

Sequential Read : 16.415 MB/s
Sequential Write : 5.882 MB/s
Random Read 512KB : 16.420 MB/s
Random Write 512KB : 3.270 MB/s
Random Read 4KB (QD=1) : 4.078 MB/s [ 995.6 IOPS]
Random Write 4KB (QD=1) : 0.025 MB/s [ 6.1 IOPS]
Random Read 4KB (QD=32) : 4.397 MB/s [ 1073.4 IOPS]
Random Write 4KB (QD=32) : 0.020 MB/s [ 4.8 IOPS]




Sandisk 8 GB UltraII SD (class 4)

Sequential Read : 20.042 MB/s
Sequential Write : 15.931 MB/s
Random Read 512KB : 19.636 MB/s
Random Write 512KB : 3.126 MB/s
Random Read 4KB (QD=1) : 3.628 MB/s [ 885.7 IOPS]
Random Write 4KB (QD=1) : 0.030 MB/s [ 7.2 IOPS]
Random Read 4KB (QD=32) : 3.662 MB/s [ 894.2 IOPS]
Random Write 4KB (QD=32) : 0.045 MB/s [ 11.1 IOPS]

Transcend SD 8GB Class 10


Sequential Read : 17.772 MB/s
Sequential Write : 12.721 MB/s
Random Read 512KB : 17.142 MB/s
Random Write 512KB : 1.723 MB/s
Random Read 4KB (QD=1) : 2.953 MB/s [ 721.1 IOPS]
Random Write 4KB (QD=1) : 0.050 MB/s [ 12.3 IOPS]
Random Read 4KB (QD=32) : 2.942 MB/s [ 718.2 IOPS]
Random Write 4KB (QD=32) : 0.057 MB/s [ 14.0 IOPS]

Conclusion:

Even though the Transcend SD memory has better specifications, the Sandisk card just blows it out of the water in terms of performance.
The CF comparison isn't really a fair one because the Ultra has better specifications, but I felt like including it anyway.

Aside from these numbers, I did a couple of practice tests and I DID notice a difference when shooting the CF cards (the Transcend card sometimes choked the buffer). I didn't notice much difference between the SD cards, which shows that, despite it's lower specification, the Sandisk performs like a madman.


And now for the less-than-1-million-dollar question: which brand would I buy, had I known this in advance?

Sandisk. They are a bit more expensive, but even the lower specced ones outperform the high-spec Transcend memory. And the cards look cooler too!

_________________
I take pictures so quickly, my highschool was "Continuous High".

I'm surprised to see that "Class 4" clearly does NOT refer to the random write speeds. Is it somehow determined by some combination of random and sequential write? And which write speed is more relevant for photography?

No, the class system is indeed the minimum writing speed, but the story is a bit more complex. For cameras, I'd look at the sequential write speed (especially for video), and writing smaller files in sequence.

Random write speeds also depend on the memory controller, and are not a general-use scenario for photographers (your camera doesn't place pictures all over the card, it just starts at the beginning of the memory space).

_________________
I take pictures so quickly, my highschool was "Continuous High".

Updated with Transcend tests, conclusion added.

_________________
I take pictures so quickly, my highschool was "Continuous High".

yes,Sandisk are better overall. I like Kingston a lot as a brand,but when I'll get a semi-pro or pro camera,Sandisk will be the way to go (or Lexar)

_________________
Gear: Nikon D80, 18-105mm, 35mm F/1.8, 85mm F/1.8, SB-600
Visit my work here

I've had two Kingston products fail on me (which is a 100% failure rate for me), so I don't really trust them anymore. (It's probably just bad luck though).

Sandisk and Lexar do seem to be the way to go.

_________________
I take pictures so quickly, my highschool was "Continuous High".

I guess I still can't tell what the "class" designation means, then. It clearly doesn't refer to the sequential write speed, since the "class 4" Sandisk card gets 16MB/s. If the class refers to some combination of the sequential and random write speeds (as I suspect it does), then how useful is it for photography purposes?

In any case, I'm fairly certain most SD cards will have sequential write speeds that my camera (1000D) cannot saturate, so I'm not particularly worried. I'm mostly just curious.

AFAIK Class refers to the absolute minimum write speed the card should be able to keep at all times, but apparently that is for Sequential writing only. Keep in mind though that these were nice conditions for the cards. Freshly formatted, no files on the card, no fragmentation.

_________________
I take pictures so quickly, my highschool was "Continuous High".

Kingston is not giving that quality which given in stat, I have used many products of Kingston Brands but i am not satisfied.

_________________
CD Replication

Kingston was better but now its up to old standards

_________________
SanDisk