Best Memory Cards Sony FX3

Sony FX3 Memory Card Recommendations

There are three different types of cards you should look at for the Sony FX3 and it really comes down to each shooter’s use case scenario. 

For S&Q high frame rate shooting, CFexpress Type A cards will guarantee performance.

To record 600Mbps with the H.264 codec, you will need V90 UHS-II SD cards at a minimum. For H.265 recording, will be able to use V60 UHS-II SD cards which are the best bang for the buck.

If you can afford it, the Sony CFe Type A is the best memory card for the Sony FX3 as it will allow you to do everything.

Sony FX3 – Amazon / Adorama / B&H

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Sony FX3 Memory Card Compatibility

The Sony FX3 can take two different types of memory cards in the same slot.  SD cards (UHS-I and UHS-II cards), and CFexpress type A cards.

Do you need CFexpress Type A cards For the Sony FX3?

You only need CFexpress Type-A cards if you record at higher frame rates in the S&Q mode.

For all other situations, UHS-II V90 cards work fine.

Can You Use V60 UHS-II Cards?

If you’ve decided that you fall into the category of someone who is not using S&Q high frame rates, then you have a few options for UHS-II cards. V60, or v90.

Just remember, if you need to shoot S&Q with some fast frame rates, you’ll need CFexpress Type A cards. You can always shoot at fast frame rates like 120p in the XAVC modes without the CFexpress Type A cards.

V90 cards will allow you to shoot H.264 at 600Mbps, and V60 cards are all you need for H.265 video which records at 280Mbps.

CFexpress Type A vs SD Cards, what’s the difference?

The difference between these two cards mainly comes down to size and speed. CFexpress Type A cards are much faster and slightly smaller.

CFexpres Type A cards use a PCIe 3.0 Interface with a single lane of throughput. Most CFexpress cameras today are just using a dual-lane PCIe 2.0 CFexpress Type B interface which should see similar speeds as a PCIe 3.0 camera. Which we don’t know yet if The Sony A7sIII or FX3 has such capabilities. – More tests coming this summer when I’m back in the USA.

Sony FX3 Specs

To see how each UHS-II memory card performs in Sony cameras, here is a speed test from the Sony A9II.

Memory Card Speed Test | Fastest Memory Cards

These tests are taken with continuous bursts high at ISO 100. The buffer is filled and the time it takes to clear the buffer is calculated against the record times. USB-C read and write speeds are benchmarked with Windows 10 using a crystal disk, and in-camera benchmarks at taken with the Sony A7sIII.

These benchmarks show the speed of cards in the Sony A7rV since the A7sIII will have a bottomless buffer with the CFxA cards so they are impossible to test. Using the A7rV tests give you a better idea of how each card performs with Sony hardware.

Speeds are in MB/s.

Best Memory Cards For 4k Video

Sony FX3 Video Specs & Recording Modes

With the Sony FX3, there are various record modes using different codecs. It gets a little complicated so here is the breakdown.

What’s new to the Sony FX3 compared to older Sony cameras is the XAVC HS and the XAVC S-I.

Should I Shoot XAVC HS, XAVC H-I, or XAVC S?

People often the different XAVC settings confused with codecs. They are not the same. XAVC HS, or H-I, or S are just containers that allow for different specs and capabilities.

These new containers you’re seeing in the FX3 can record 10-bit 4:2:2, with the main difference being the codec they allow, H.265 or H.264.

XAVC HS allows for H.265 recording.

XAVC S and S-I still only record to H.264. 

XAVC S-I allows for all intra-recording. Meaning keyframes on every frame, which is ideally what you want.

Today you should record in H.265 if your computer can handle it. H.265 offers better compression with smaller file sizes. This is why you see the camera only outputting 280Mbps H.265 files, vs the 600Mbps H.264 files.

New CPUs are getting better at encoding and decoding H.265. You may need to switch over to an M1 mac or a new Intel processor (Alder Lake, possibly Tiger Lake) to edit H.265 with smooth performance. – I’m not sure where AMD is here. I haven’t heard anything about them supporting H.265 10-bit 4:2:2 yet.

Sony FX3 Recording Specs & Details

Record Limit: Unlimited
Audio File Format: AAC, Linear PCM

Sony FX3 Record Times – Memory Card Capacity

This table shows the different recording modes and how much time they use for different card sizes. To get your own numbers, I have to build a bitrate-to-time converter.

Best Memory Cards Sony FX3 Conclusions

Buying memory cards for the FX3 is a little tricky since there are so many codecs and specs. It’s a bit of a mess.

But the takeaway is, shoot H.265 if you can and this will allow you to use V60 UHS-II cards. Then maybe pick up a smaller CFexpress card to shoot 120p S&Q for those times you need that type of footage.

UHD 4k H.265 XAVC HS, v60 UHS-II cards are fine.

UHD 4k H.264 XAVC S-I, you will need v90 UHS-II cards.

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