[Mallee Boy]

This is probably in the wrong forum, but I'll start it here so as it gets maximum exposure. If it has to be shifted, thats fine.

Can anyone prepare a summary of SD cards and what the industry standards actually mean . I have been looking for extra cards to feed my K20D and what I have learnt is that in SDHC (which will not work in earlier model dslr's or card readers) there are three standards: Class 2; Class 4 & Class 6. My limited knowledge is that the classes refer to the writing speed of the card.

So if anyone here is able to summarise what is different in SD cards, that would be a great resource.

Cheers

[joefru]

The classes refer to the data transfer speed of the card; Class 6 is the fastest. Only the SDHC cards have class specifications. And correct, a great many not-very-old devices are SDHC-INcompatible. I only have one card reader that will read my SDHC cards. My internal SD reader, my Wii, nor my Palm T|X will recognize an SDHC.

I'm actually thinking of ditching my 8GB SDHC in favor of a handful of high-speed 2GB SDs, for the compatibility reason alone. Plus the whole all-eggs-in-one-basket thing.

As far as speed ratings on SD cards go, they're marked with more understandable speeds, like 30x, 60x, 180x, etc. I have a 2GB non-speed-marked SD card, and it takes noticable longer to clear the buffer after a burst, compared to my Class 6 SDHC. Other than that, though, there's no difference.

[Arpe]

SDHC cards WILL work in earlier DSLRs, from istDs on, if they have latest firmware.

[Gimbal]

I have tested a 4GB Transcend 150x, a 4GB Transcend sdhc class 6 and a 4GB Sandisk extreme III on my k10d. The extreme III was the only card that didn't slow down the camera.

[Derridale]

SanDisk 4Gb SDHC cards come with a very handy little USB Reader/Adapter. Very small, fits in any sidepocket of even the smallest camera case. I bought a couple of 4Gb SanDisk cards, and therefore have two readers. One lives in the camera case, one lives in my laptop case.

My new laptop and desktop PCs, have SDHC card readers built in anyway - the PC world is slowly catching up to SDHC. My Epson P5000 storage device also reads the SDHC cards no problem. And all my images are RAW files in Adobe DNG format.

In addition to the SanDisk 4Gb cards, I also have a couple of Kingston 8Gb Class 6 high-speed cards. The difference is mainly noticeable on burst shooting, and also on playback scrolling through RAW images.

[KrisK10D]

SanDisk 4Gb SDHC cards come with a very handy little USB Reader/Adapter. Very small, fits in any sidepocket of even the smallest camera case. I bought a couple of 4Gb SanDisk cards, and therefore have two readers. One lives in the camera case, one lives in my laptop case.

This is the reason why I got a Lexar card. It doesn't matter where I am or who's equipment I'm using... just about every device on the planet has a USB slot

[Lloydy]

I use either a 2gb Extreme 111 sd or a 8 gb Kingston sdhc in my K10

My built in computer card reader will read the 2gb but the 8gb will lock the card readers completely requiring a reboot of the computer.

But the K10 has a download lead and that works fine, very fast actually so that's all I use now.

[Douglas_of_Sweden]

The classes refer to the data transfer speed of the card; Class 6 is the fastest. Only the SDHC cards have class specifications. And correct, a great many not-very-old devices are SDHC-INcompatible. I only have one card reader that will read my SDHC cards. My internal SD reader, my Wii, nor my Palm T|X will recognize an SDHC.

I'm actually thinking of ditching my 8GB SDHC in favor of a handful of high-speed 2GB SDs, for the compatibility reason alone. Plus the whole all-eggs-in-one-basket thing.

As far as speed ratings on SD cards go, they're marked with more understandable speeds, like 30x, 60x, 180x, etc. I have a 2GB non-speed-marked SD card, and it takes noticable longer to clear the buffer after a burst, compared to my Class 6 SDHC. Other than that, though, there's no difference.

I've goon for the same solution. A bunch of good 2 GB instead of these awfully large new ones that are often a bit slower, and if I waste one 2 gig, it is a smaller catastrophe.