Canon R6 III Memory Card Speed & Buffer Tests - Over 60 Cards Tested

About Our Tests

All of our in-camera tests were carried out with the Canon R6 III and firmware 1.0.2.

The figures presented here are based on our test conditions.

If you are testing this yourself, you will most likely see slightly different results because a different scene will generate different file sizes.

Our Recommended Cards & Readers

The Canon EOS R6 III is only writing to the fastest CFexpress cards at an average speed of around 505 MB/s when shooting RAW + JPEG L at 40 FPS with the file sizes used in our tests.

Therefore, if you base your purchase decision on the fastest card label speeds you will often be throwing money away. Also, card label speeds normally only show the maximum read and write speeds, not the sustained speeds..

Other than a few CFexpress cards that perform poorly, the majority of cards tested all perform the same. So our advice would be to either go with your preferred brand, or the best deal available at the time.

If we had to recommend one CFexpress Type B card then we would recommend the Delkin Devices CFexpress 2.0 POWER G4 cards for capacities under 512GB. Or the 4.0 POWER cards for 512GB and larger. These cards offer great performance and good value for money.

There is one exception here. And that's if you shoot in very hot environments or are filling and formatting your memory cards on a daily basis, then you might be best going with a card that features pSLC NAND memory.

pSLC based cards offer increased performance, durability, better heat management, and superior temperature tolerance over 3D TLC NAND which the majority of CFexpress cards are using.

However, not all manufacturers state the type of NAND memory used in their cards. We do know that the following cards are using pSLC NAND memory.

• Delkin Devices Black Series CFexpress 4.0 Type B VPG 400
• Nextorage NX-B2 PRO Series CFexpress 4.0 Type B 
• Lexar Professional DIAMOND Series 4.0 Type B
• Novachips Extreme CFexpress Series 4.0 Type B

The downside is, pSLC cards are often the most expensive cards to buy.

There a lot more variance in performance when it comes to the UHS-II SD cards. The V90 rated cards all perform very close to each other, but the write performance of the V60 cards varies a lot more.

For action shooters who need the buffer to clear quickly and want to use as SD card for backup, we would recommend going with a V90 rated card, such as the Delkin Devices POWER UHS-II V90 card. 

If you don't shoot much action then you can save some money by purchasing a V60 rated card instead. 

For video shooters wanting to shoot 7k RAW Open Gate which is 2600 Mbps we would recommend a VPG 400 rated card for guaranteed performance. 

As for card readers, our advice is to purchase the same brand of reader as your cards to avoid any compatibility issues. Most readers will work fine with different cards, but sometimes problems can arise.

We really hope that you have found this article to be helpful. If you have any questions, please do drop them in the comments below.