Signifying the gradual spread of a new generation of memory card technology for cameras and videocameras, Transcend on Tuesday announced its first SDXC card, a 64GB Class 10 model.
The Secure Digital memory card family has a relatively long and prosperous lineage. Its second generation to today's prevailing SDHC incarnation comes with capacities of up to 32GB, but SDXC (Extended Capacity) starts there and goes to 2TB, offering faster data transfer speeds, too.
Transcend didn't announce availability or a price, but don't expect it to be cheap. SanDisk's slower 64GB Class 4 SDXC card costs about $220 right now, and Panasonic's 64GB Class 10 SDXC card costs about $500.
Another Transcend competitor for cost-conscious buyers, Kingston, announced its 64GB SDXC card earlier this month with a $500 price tag, too. Expect prices to drop gradually as more SDXC cards and more products that use SDXC arrive on the market.
In earlier days, the SD Card industry consortium that oversees the Secure Digital technology defined Class 10 as able to write data at a rate of 10 megabytes per second, but now the organization has moved to a qualitative definition of SD card transfer speeds; Class 10 is fast enough to record full high-definition video and sequences of high-resolution still images. A separate, faster speed category rating called UHS (Ultra High Speed) also is arriving; it "defines bus-interface speeds up to 104 megabytes per second for greater device performance in SDXC and SDHC host products," SD Card said.
For some real-world tests of many cards across a range of cameras, check Rob Galbraith's useful database of flash memory performance measurements.
SDXC appears poised to at least match the dominance of SDHC, with early mainstream products such as Canon's Rebel T2i (aka 550D) camera employing the standard. One interesting question for the industry is whether SDXC will make incursions onto the CompactFlash format. CF has led SD when it comes to capacity and transfer speeds, but SD is catching up, has a cost advantage, and has gradually displaced CF first from point-and-shoot cameras and later many SLRs as well.
One interesting data point will be the expected successor to Canon's flagship SLR, the 1Ds Mark III. It has memory slots for both SDHC and CompactFlash. It's not likely this device will ditch CompactFlash, given professional photographers' investment in the technology, but it seems likely any second slot would be SDXC for speed, capacity, and longevity reasons.