Sandisk Extreme III 20mb/s vs. 30mb/s Burst Test
For this test I used a Gen 1 camera (D40x) and a Gen 2 camera (D90). This is by no means a scientific or data transfer test. I wanted to show how each card performs in the real world (i.e., in burst mode).

The following cards were used:
Sandisk Extreme III 4GB 20mb/s card
Sandisk Extreme III 4GB 30mb/s card

I kept the settings on each camera equal, including the lens, so that no one could argue about variables of any kind:


  • D40x
  • ISO 100
  • 1/4000th
  • WB Auto
  • 3fps
  • RAW
  • Large-Fine JPEG
  • Nikkor 50mm MKII f1.8 AIS @ f1.8.
  • D90
  • ISO 100
  • 1/4000th
  • WB Auto
  • 4.5fps
  • RAW
  • Large-Fine JPEG
  • Nikkor 50mm MKII f1.8 AIS @ f1.8.

Sandisk Extreme III 20mb/s vs. 30mb/s



If the video doesn't play, or is unavailable click here to access the Vimeo site. It's a long video, and to spare you the trouble of going through it, read the results below.


Conclusions:
On a Gen 1 camera there was no difference in performance shooting RAW or Large-Fine JPEG. I managed to shoot 6 consecutive RAW frames at 3fps, and 100 large-fine JPEG frames at 3fps with both cards.

On a Gen 2 camera there was a slight difference in performance shooting RAW. There was no difference shooting Large-Fine JPEG. I managed to shoot ~9-10 RAW frames with the 20mb/s Extreme III card, and I managed to shoot ~11/12 RAW frames with the 30mb/s Extreme III card***. Both cards performed flawlessly shooting Large-Fine JPEG, and reached 100 frames at 4.5fps without slowing down.

Recommendations:
There is no difference in terms of burst speed and reaching the max RAW and JPEG capabilities of either camera. In terms of writing to the card after the buffer is full, there are better tests than what I've done, and I can tell you that the 30mb/s card does a bit better of a job, but the difference isn't huge.

If you like people to gaze at your gear in awe, buy the 30mb/s version. If you care more about your wallet, buy the cheaper card and know that on a Gen 1 camera the cheaper card offers exactly what the more expensive card gives you. If you have a Gen 2 camera, the only difference will be if you shoot RAW, and it's a difference of 2-3 frames***. I guess if you shoot sports using RAW those extra frames will count, but if you're just an amateur or a hobby photographer, save your money and buy the 20mb/s card.  

*** According to the manual the D90 should only reach 9 RAW frames at a burst of 4.5fps. However, using the 30mb/s card it appears that I pushed that limit. I am not sure if I actually did, as it is not easy to listen to the break between the final RAW frame and when the camera starts stuttering at such a high frame rate. That is why I said "~" (approximately). In all honesty I do not think there was any difference, though my ears told me otherwise. See the recommendation above.

**A special thank you to Mark of Modern Mango Studios for lending me his D90 for this test.**