8th April 2008, 09:59 PM
It was a lazy, rainy Sunday afternoon when I came up with the idea of comparing all the flash memory cards that I had. Just for the fun of it! The methods and results are below. I've put up the details here to share the info with fellow CSers. This is not meant to be a definitive test nor a recommendation of certain brand of card!! Please don't interpret my post in that fashion. Just for fun. OK?
The following test is a comparison of speeds between different compact flash cards. A SDHC card and an old SD card have been thrown in for comparison too. Note that this test is NOT a measure of how many MB/s of transfer speed.
I used a Canon 1Ds MkIII mounted on a tripod. The test picture was a colour pattern taken off a computer monitor to ensure that the "target" was fixed and did not change in any way. The camera was set to a 5 frame bracketing mode and put into high speed multiple shot mode. This would ensure that on triggering the camera, it would take 5 frames and nothing more. The lens was switched to manual focussing mode and pre-focussed. This would ensure that there would be no time lag for focussing by the camera. All other camera settings like ISO, aperture, etc, were set and kept unchanged for all the cards. The total size of the 5 frames was about 188MB.
(Note: All cards were bought retail. One of the cards marked fake is, well, fake!)
1. Format card in camera. (One exception - see discussion below)
2. Press the shutter release button and start stopwatch at the same time.
3. Stop stopwatch after camera writing light goes off.
4. Repeat test 3 times and take average.
Results: (fastest first)
1. Sandisk Ducati 8GB CF -- 8.95 sec
2. Sandisk Extreme III 8GB CF -- 14.19 sec
3. Kingston Elite Pro 512MB SD -- 15.37 sec
4. Lexar 80x 2GB CF -- 19.89 sec
5. Lexar 80x 1GB CF -- 20.31 sec
6. Sandisk Ultra II 8GB SDHC -- 21.25 sec
7. Transcend 133x 32GB CF -- 21.96 sec
8. Hitachi MicroDrive 6GB -- 28.10 sec
9. Sandisk 1GB CF -- 34.60 sec
10. Transcend 1GB CF -- 41.10 sec
11. *FAKE* Sandisk Extreme IV 8GB CF -- 47.90 sec
12. Hagiwara 1GB CF -- 117.67 sec
A couple of surprises here. The Hagiwara 1GB and Transcend 1GB were bought many years ago when I was using my Canon D60. These are amongst the oldest CF cards I possess that are 1GB or larger. Surprisingly the Hagiwara card was really really slow!! I thought that it was an isolated problem but when I tested my other Hagiwara 1GB CF (I have 2), I got the same result. Its surprising that the discrepancy between timings of my 2 oldest CF cards was so large! On the other hand, the Transcend 1GB could still hold out to a plain gardern variety Sandisk 1GB CF that was purchased much later. The other surprise was the Kingston Elite Pro 512MB SD card. Can't remember exactly but I probably got this several years ago. This card needed to be formatted twice because its relatively small capacity couldn't swallow 3 rounds of testing! It was really amazing that the speed of this little SD card almost matched the Sandisk Extreme III 8GB CF!! Not only that, it was noticeably faster than the Sandisk Ultra II 8GB SDHC!! Didn't see that one coming.
Now I don't know the internal workings of the fake Sandisk CF card but it was visibly slow. Only succeeded in beating my old Hagiwaras.
So there you go folks! A bit of bed time reading.