Just as we start to accept UHS-II into our lives, and before UHS-III is even a real thing, a new standard hits the streets. That’s right, folks, SD Express has now been announced, offering data transfer speeds of up to 985MB/sec. It also bumps up the maximum capacity from SDCX’s 2TB to the new SDUC’s 128TB.
SD Express uses PCIe and NVMe interfaces to deliver these faster transfer speeds. To read about how the SD Association talks about SD Express, it’s almost like they want or expect people to start using these as portable SSD replacements for general use.
With SD Express we’re offering an entirely new level of memory card with faster protocols turning cards into a removable SSD.
SD 7.0 delivers revolutionary innovations to anticipate the needs of forthcoming devices and content rich and speed hungry applications
– Hiroyuki Sakamoto, SDA President
It’s true that devices seem to be far more data hungry with each new generation that is released. 360° cameras have gone from 1080p to 4K with now 8K becoming the new norm. Cameras such as the Panasonic GH5 and the soon-to-be-released Blackmagic Pocket Cinema Camera 4K are already capable of some pretty ridiculous bitrates, too.
And it’s only going to get more demanding as cameras of the future start to become capable of 4K 120fps video with increased bitrate codecs. Not to mention RAW video. While a number of cameras already shoot CinemaDNG or other RAW formats, ProRes RAW seems to have been received quite favourably so far – even though you can currently only edit it in Final Cut Pro.
The new cards will come in three capacity formats. SDHC (up to 32GB), SDXC (up to 2TB) and SDUC (up to 128TB). To get the fast transfer speeds, the second row of pins currently in use on UHS-II cards (and to be used on UHS-III cards) is to be repurposed for the new standard. They will use the PCIe 3.0 spec and NVMe v1.3 protocols on those pins instead. But this means that UHS-II and UHS-III cards will essentially max out at 104MB/sec when used on SD Express devices (when they eventually exist).
So, even when SD Express does show up, I wouldn’t go throwing out your old cards just yet. If you’re shooting a camera that utilises UHS-II or UHS-III, you’re still going to be better off with UHS-II or UHS-III cards than the new format. And, well, even UHS-III doesn’t actually exist yet, so who knows when we’ll see SD Express?
But it does also mean that when SD Express devices do show up, you’ll almost certainly need new memory cards to utilise them.
SD Express is not the only memory card format of the future, though. Set to replace both CFast and XQD, CFexpress prototypes have already been shown off, offering a whopping 1.4GB/sec transfer rate and 1TB capacity. So, it will be interesting to see how far that technology has come along by the time SD Express actually comes out.
You can read about the new specification in its entirety in a new SD Association white paper.
[via Tech Powerup]