Reviews |OWC Atlas Pro CFexpress Type B 512GB memory card

OWC Atlas Pro CFexpress Type B 512GB memory card

A High-Performance, Durable, and Affordable Memory Solution for Advanced Photography Needs.

OWC Atlas Pro CFexpress Type B 512GB memory card

Price when reviewed



Our Verdict

The OWC Atlas Pro CFexpress Type B memory card, OWC’s entry-level offering in the CFexpress range, impresses with a balance of high performance and affordability. Priced below the premium Atlas Ultra cards, it still more than holds its own with outstanding transfer speeds.

The card’s physical design meets all the usual CFExpress standards and ensures it fits on all of the cameras and devices it should. Durability is given, withstanding the usual rigours of photography life, or at least life in a side pocket of my backpack and the camera, and it survived the usual knocks that you would expect.

With a substantial 512GB capacity, it’s more than sufficient for a substantial archive of images and videos, and with the latest firmware updating the cards to new heights of transfer speed, there’s little else on the market that comes close to this performance. If you’re in the market for a CFExpress card, the Atlas Pro, priced well under £200, makes absolute sense.


  • Exceptional Speed Performance
  • Robust, Durable Build
  • Substantial Storage Capacity


  • Relatively Expensive Investment

What is the OWC Atlas Pro CFexpress Type B 512GB memory card?

The OWC Atlas Pro CFexpress Type B is a high-capacity (512GB) memory card designed for cameras like the Canon EOS R5 and Nikon Z8. Meanwhile, Sony’s A7 IV and other Sony mirrorless bodies have adopted smaller and somewhat slower Type-A cards. The Atlas Pro pushes the boundaries of camera storage, with an option for this 512GB version that I’ve looked at in this test and a smaller 256GB version. If you want the larger capacity options, then OWC does the Ultra range of professional cards.

One of the big points of the OWC cards is that they are updateable with the new firmware, which can unlock features but, more commonly, just boost the performance. This update is applied using an OWC card reader and the Innergize software, with the most recent firmware update significantly boosting this model’s performance.

OWC Atlas Pro CFexpress Type B 512GB memory card


  • Write Speed: Up to 3000MB/s
  • Read Speed: Up to 3650MB/s
  • Sustained Write Speed: Up to 800MB/s
  • Compliance: Meets CFexpress Type B 1.0, 2.0, and up to 4.0 specifications
  • Durability: Impact, bend, shock, ESD, UV ray, and x-ray resistant
  • Operating Temperature: 10.4°F to 161.6°F (-12°C to 72°C)
  • Non-Operating Temperature: -4°F to 185°F (-20°C to 85°C)
  • Memory Card Bus: PCIe 4.0 x2

Build and Handling

The OWC Atlas Pro CFexpress Type B memory card is built to withstand the demands of professional photographers and filmmakers. The exterior construction is all well made and finished with a combination of the usual plastics and metals, providing a reassuring feel. This composition not only ensures longevity but also instils confidence in its ability to withstand frequent usage and the inevitable rough handling that comes with all types and levels of photography.

The card does, of course, adhere to the usual CFexpress Type B standard and fits into and out of camera slots and card readers with the ease you’d hope.

When it comes to where the Atlas Pro can be used, it’s built to be resilient against extreme environmental conditions and resistant to shocks, impacts, and extreme temperatures, which all make it a reliable choice for photographers and videographers. Even those working in extreme conditions, from freezing Arctic landscapes to the intense heat of deserts.

OWC Atlas Pro CFexpress Type B 512GB memory cardThe card also incorporates enhanced safety features that include resistance to electrostatic discharge (ESD), UV rays, and X-rays, so it should make it through all the scanners in one piece. However, it is probably still a good idea to have a backup of the Artic image files before it gets X-rayed.


The OWC Atlas Pro CFexpress Type B memory card’s standout feature is the fact that it offers peak read speeds reaching up to 3650MB/s and write speeds up to 3000MB/s; this means that it is perfectly equipped to handle rapid burst RAW image sequences and high bitrate video recording up to 6K.

The Atlas Pro CFexpress doesn’t just impress with speed; it also offers a generous storage capacity. Available in sizes from 256GB to our review sample at 512GB, it provides ample space to store an extensive array of high-resolution photographs and lengthy video recordings. This spacious storage makes it ideal for lengthy shooting sessions and significant projects that require a vast amount of data storage, which is great if you are venturing off on an adventure somewhere.

In terms of compatibility, the Atlas Pro CFexpress is fully compatible with a broad range of mirrorless cameras, including XQD format cameras that have been updated to support CFexpress Type B.

OWC Atlas Pro CFexpress Type B 512GB memory card

Although this range of cards has been around for a while, the ability to update the firmware sees this card leap in performance due to the upgrade to the latest CFexpress Type B 4.0 specification while also meeting Type B 1.0 and 2.0 specifications. This forward and backward compliance positions the Atlas Pro as a future-proof choice.

Durability is another key feature of the Atlas Pro CFexpress. It’s designed to endure tough conditions, being resistant to impacts, bends, shocks, ESD, UV rays, and X-rays. This rugged build quality ensures the card can withstand the harshest environments, providing reliability and peace of mind for users, irrespective of their shooting locations.


The OWC Atlas Pro CFexpress card is a standout in terms of performance. Its build quality is unmistakably OWC – robust and built to last a lifetime. Compatibility was flawless across various camera bodies, including the demanding Canon EOS R5 C, keeping pace effortlessly with all camera settings, including RAW lite options. The card’s speed also impressed during file transfers, offering a noticeable advantage when downloading the content to the computer.

OWC Atlas Pro CFexpress Type B 512GB memory card

In real-world testing, the card performed admirably. Utilising the Blackmagic Disk Speed Test, the Atlas Pro demonstrated exceptional read and write speeds:

– Write: 3442.1MB/s
– Read: 2824MB/s

These results are indicative of the card’s capability to handle high-intensity photography and videography tasks without an issue. It also highlights a performance boost this firmware update to CFExpress 4.0 compatibility has on the cards, although you do need a card reader that is also matched with that performance.

Final thoughts

The OWC Atlas Pro CFexpress Type B 512GB card, with its latest firmware update, quality, durability, and performance, is an impressive option at a really decent price.

This card is an ideal choice if you’re a professional or enthusiast who requires high-speed data transfer and substantial storage capacity, even if you’re not the price of this or the cheaper 256GB version, which is still substantial, is a great option and a bit of a no brainer for anyone who owns a camera body that utilises the CFExpress format.