Move to the Head of the Class!

January 8, 2012 7:13 AM

Can I use the highest Class SDHC card, as long as my device accepts SDHC?

(I thought this would be an easily Google-able question, but it doesn't seem to be, so here I am!)

I use a Class 4 SDHC card for my digital camera, and I have to wait a long time after taking a few photos for it to "catch up" and let me take more photos. I borrowed a Class 6 SDHC card and it performed much better. Can I use a Class 10 SDHC (or higher, if they exist) in my camera? I read the manual over and over, but it's a few years old, so it doesn't say what Classes I can use, other than I can use up to 32GB SDHC...

Same question with my video camera: I currently use a Class 6 SDHC card because the manual says "must use a Class 6 SDHC card." But it doesn't say if I can use any higher Class.

tl;dr: As long as my device can use an SDHC card, can I use any Class card that is at or higher than required per the manual?

posted by TinWhistle to technology (5 answers total)

I think the answer is "yes" but it may not take advantage of the full performance. In other words, a class 10 would work, but would act as if it was class 6.
posted by Chocolate Pickle at 7:17 AM on January 8, 2012

I just did some research on this because I needed a card for a gopro camers. I found this wiki link very helpful.

From what I can tell the higher class the better. However, for my dslr, on recommendation of a friend, I bought an UHS class 6 card that gets 30mbs. It was way more expensive, but when taking hundreds (like 600 - 800) of photos, the transfer rate from the card to my mac was significantly faster than some of my other cards. My camera doesn't seem to perform any differently between a regular class 10 and the UHS class 6. This might be better if you take a lot of video.
posted by getmetoSF at 7:49 AM on January 8, 2012

*camera. Ha!

Also, UHS is Ultra High Speed and I bought it about 3+ yrs ago. The price of the card has come down quite a bit since then.
posted by getmetoSF at 7:51 AM on January 8, 2012

The "class" of the card just means "it can write sequential data at least this fast." So a higher-class card just means it can stream write faster. This doesn't mean your camera will be able to *send* it data any faster, so it might not make a difference.

It's worth noting that the performance of a high-class card can, oddly enough, be worse in some cases. In order to achieve high class ratings but still keep costs down (because people rarely buy based on value), SD manufacturers will do things like go to gigantic page sizes. This means that random small writes on that card will be horribly slow because the card will have to do big page re-write operations for every small change. So a class 10 card might scream in your camera (which pretty much only does large sequential reads and writes) but absolutely creep in your phone (which does lots of small reads and writes).
posted by introp at 10:37 AM on January 8, 2012

Pretty sure that to get the benefits of UHS cards, your host devices need to support UHS — it's not automatically implied just by being an SD card device. (UHS is an extension to standard SD that supports 4-bit wide transfers at a higher than normal clock rate, I think.) If you use a UHS card in a non-UHS device, it'll behave as a standard SD card.

Definitely worth the money if your camera supports it, but I wouldn't shell out unless you are pretty confident that it does.
posted by Kadin2048 at 10:03 PM on January 8, 2012