I recently sent this question to Dave at JVC, but have not heard back yet.

I wrote to ask if JVC is planning on making, or for that matter knows if the GY-HM700 is compatible with the new 64Gig SDXC Class 10 Cards being marketed by Panasonic and others.

Here are a few paragraphs from a recently received an email from B&H regarding this subject and notice about the new cards coming available in the very near future.

"...For photographers and videographers who can never get too much storage, Panasonic announced SDXC cards in 64- and 48 Gigabyte capacities. SDXC is the next generation after SDHC cards to retain the size of SD memory cards. SDXC cards are built for capacities greater than 32GB with a future roadmap up to 2TB. (You'll have to wait for a future CES to lose a 2 TB card.) Besides Panasonic, Canon has endorsed the SDXC format.

The RP-SDW64GE1K (64 GB) and RP-SDW48GE1K (48 GB) are Panasonic's largest-sized Gold cards with Class 10 speed specification. Class 10 affords data transfer rates at up to 22 megabits per second (MB/s). Both cards will be globally introduced in February with suggested retail prices of $599.95 and $449.95, respectively.

The 64 GB SDXC card is appropriate for recording AVCHD high definition video or RAW still photos. When used with Panasonic's newly-released camcorders, such as the Panasonic HDC-TM55, the 64 GB SDXC Memory Card can record up to 8 hours and 30 minutes of video at the highest quality. Interestingly, the 48 GB SDXC Memory Card will have nearly the same capacity as a dual-layer Blu-ray Disc. For still photography, all of Panasonic's newly-introduced Lumix cameras are SDXC-compatible. The 64 GB card will hold approximately 18,240 images while the 48 GB card will store about 13,470 images using a 12 Megapixel camera set to capture images at 4000 x 3000 pixels in normal mode...."

Does anyone else know if these cards are supported? Although not cheap, having the ability to go up to a total of 128 Gig on board is a nice thought.

Please let me know. Thanks in advance.

Steve Nordahl
Bethlehem, Pa.

Hey Steve, This is my second try at a reply, so I hope this one goes through. I don't think the HM700 is "ready" for the SDXC cards because SDXC cards run exFAT file structure, as opposed to FAT32 that SDHC cards run. Microsoft owns exFAT and it is the new file structure they are using in Windows Vista / 7. Having said that, who knows how long until they (Microsoft) lets other users (Mac) in on the exFAT technology. You may know but others may not, FAT32 (segments) or breaks files when they run longer than 4Gig. That is why many users see multiple files on long clips, rather than one file. exFAT doesnt have that 4Gig limitation, so its files can be larger (and faster) and thus the theoretical storage size and speed of the cards themselves can be larger. I hope that JVC will do a firmware update later this year to be "ready" when the SDXC cards hit the market. But I fear the cameras will need new hardware also. This is a situation just like when SDHC came out. A device that could "only" read an SD card (FAT16) could not read an SDHC (FAT32) card. Fortunately, when SDXC devices come out, they will be able to read (and use) all 3 formats of cards. I have been researching this subject myself for a while, and like you my JVC rep didnt have any answers. He had no idea if and when the HM series would be able to use the SDXC cards. It didnt help matters much that he didnt even know they existed.
We will see the new cards in the next generation of phones and wireless devices, probably before the technology filters down to us in the video industry.

Look on the bright side the bigger the card the more to lose.