TESTED: 256GB OWC Atlas S Pro SDXC Card (plus comparison to Sony TOUGH SF-G)
Related: camera cards, CFExpress camera storage card, Other World Computing, OWC Atlas camera storage cards, SDXC camera storage card
re: Sony A7R IV: Which High-Speed and High-Capacity SDXC Cards Are Best?
re: Fast Camera Card Storage for Sony A1: CFExpress Type A (NOT Type B), or SDXC
re: OWC Atlas S Pro SDXC Camera Cards — Ultra High Flash Durability, Ultra High Speed, 5-Year Warranty
Special limited-time pricing as of Dec 3: $100 off the 256GB card or $30 off the 64GB card, see below.
Background
Most cameras these days still take SDXC cards. I favor them because of built-in card readers on my computers and because they work in most of the cameras I use.
Newer cameras like the Sony A1 take either SDXC or CFExpress Type A (some take CF Express Type B). The Sony CFExpress Type A cards for the Sony A1 are excellent, but they are not without two significant downsides. First they require a separate card reader* and when traveling that’s a hassle (and a serious headache if you forget it!). I’d rather use the space for a 2TB OWC Envoy Pro Elektron than carry along a card reader that I ought not to need at all.
CFExpress Type A cards also still rather expensive, costing 2X as much perGB vs cards like the OWC Atlas S Pro. For example, $398 for Sony’s 160GB card vs $299 for the the 256GB Atlas S Pro. So SDXC looks very attractive on price, but a problem in 2021 has been very poor availability of the Sony 128GB and 256GB SDXC cards. Enter the OWC Atlas S Pro with no availability issues as I write this.
I greatly prefer at least 256GB capacity so that I do not have to erase the card every few days, or maybe not even for the whole trip. And dual 256GB cards are even better for a set-and-forget setup for even a 3-week trip—just keep shooting and never erasing or worrying about running out of space—one less thing to carry, one less shot to miss should a card fill up, and an inherent backup to the downloaded-to-computer images.
Qualities to look for in a camera card: high sustained speed, solid physical build quality, and most of all high flash durability, so as to reduce the odds of ever getting a bad capture due to bad flash memory on the card. The last point is hardest to evaluate, so you have to trust the manufacturer’s claims to some extent.
A lot of camera cards quote burst speeds, which don’t hold up with extended writes. Maybe this matters to you, maybe not, but for example the Sony CFExpress Type A TOUGH card is insanely fast in burst mode but drops up to 70% in speed with extended writes.
* UPDATE: I ended up buying two of the Rocketek CFexpress Card Reader Type A @AMAZON, one for home, one for my Sprinter travel van.
Durability
Flash Memory Speed and Reliability: SLC NAND, pSLC NAND, MLC NAND, TLC NAND
The OWC Atlas S Pro SDXC camera cards use pSLC NAND, which is about 10X more durable than the flash used in many average/ordinary SDXC cards. Very few SDXC cards even quote a duty cycle, but OWC does:
7310TB total bytes written (TBW), equal to 2862 GB per day for 7 years.
All the digital images I’ve ever shot over the past 15 years add up to about 20TB. So with the OWC Atlas S Pro card, I’d need to shoot another 6990TB of images to wear the card out. I need to get myself a 100 gigapixel camera...!
OWC Atlas S Pro, performance
Nothing beats seeing how a card performs over a year or two of service in the field. But that’s hard to get done in a week or two.
Click through for special limited-time pricing as of Dec 3: $100 off the 256GB card.
For a sense of performance and to test compatibility, I inserted two 256GB OWC Atlas S Pro SDXC cards into the Sony A1, one in each slot, and set the camera for dual simutaneous recording. I tested burst shooting and saw strikingly fast clearance of the write buffer. Recording of 8K video also worked flawlessly.
Tested in the SD slot of the 14-port OWC Thunderbolt 3 Dock. Other card readers might perform more slowly.
Best performance I’ve ever tested in an SDXC card! Meaning consistently high write and read speeds, and little variation in performance across the entire 256GB capacity (the three big but brief dips in write speed might just be system burps rather than the card itself).
Average write speed: 280 MB/sec <=== outstanding!
Average read speed: 300 MB/sec
At 300MB/sec reads with nil deviation, downloads from camera cards will be will be a joy. This is faster than the fastest hard drive, so speeds will be lower unless using an SSD for the destination drive.
Tested with the fill-volume command of diglloydTools DiskTester. Vertical axis = MB/sec. Horizontal axis = number of files written.
Tested with the fill-volume command of diglloydTools DiskTester, ExFat file system. For the test below, 1000 files of size 254MB each were written then read back.
vs Sony TOUGH SF-G 128GB
The Sony TOUGH SF-G cards are Sony’s fastest SD cards, and they are excellent. The Sony and OWC cards read at identical speeds, but the OWC card writes slightly faster. The difference is immaterial to real-world usage, but it shows that the OWC cards are first class performers.
