Best Memory Cards Sony FX3

The Sony FX3 like the A7sIII has a very cool setup with dual UHS-II sd card slots that can also take the Cfexpress Type A card.

I think the question is, do you need to spend the extra cash on the CFexpress cards, or are UHS-II cards good enough.

This is going to depend on your use case scenario. Some people might never need a CFexpress card and this will all be spelled out in this guide, as well as some information on what cards are best for general use.

Use this guide to find the best memory cards for the Sony FX3.

Sony FX3 – Amazon / Adorama / BHphoto

Sony FX3 Must-Have Accessories

Best Memory Cards Sony FX3

The Sony FX3 has a really unique setup. It allows for two different types of memory cards in the same slot (not at the same time). Sony has done this in the past with their memory stick duo and SD card setups, and they are now allowing Type A CFexpress cards and UHS-II cards.

What’s the difference between CFexpress Type A and SD Cards?

Quite a bit, but it 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 Memory Card Recommendations

There are two types of memory cards the Sony FX3 is capable of using and you can mix and match them as you please. SD cards (UHS-I and UHS-II cards), and CFexpress type A cards.

You only need CFexpress type A cards if you record S&Q at fast frame rates.

UHS-II cards usually have two-speed classes associated with them, V90 and V60.

Most users will want V90, but if you need large cards to record some events at a lower bitrate (100-400Mbps or lower), you can save a lot of money on v60 cards.

The Sony FX3 offers two codecs with various bitrate options. These are H.265 and H.264.

H.265 is a very efficient codec and only writes at 35MB/s or 280Mbps. H.264 is not as efficient with less compression so it writes at 600Mbps or 75MB/s to make up for this difference in quality. H.265 will create smaller files with better quality than H.264, so you should use H.265 if you can learn to edit with proxies since they are easier on the CPU.

V90 UHS-II cards offer a minimum bitrate of 90MB/s. Good for 600Mbps ( 75MB/s ) H.264.

V60 UHS-II cards offer a minimum bitrate of 60MB/s. Good for 280Mbps ( 35MB/s ) H.265. – Good for long recordings, but you’ll likely need to make proxies to edit.

If you want to shoot S&Q with some higher frame rates, you’ll need CFexpress Type A cards. You can shoot with high frame rates like 120p in the different XAVC modes without the CFexpress Type A cards.

*In-Camera Speeds are from the Sony A9 II.

Sony A7sIII tests coming soon.

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

Only if you shoot S&Q at high frame rates.

What is the S & Q setting and why do you need it? 

S & Q stands for slow and quick. It creates a file that will be played back in slow motion set to your base frame rate. So the footage plays back in slow motion inside the camera.

When shooting S & Q you will need to use CFexpress Type A cards for XAVC S-I at high frame rates.

Sound is not recorded in the S & Q mode.

We typically would not record in S&Q with Sony cameras but it looks like the new FX3 might be doing something different here that will require it to use a faster memory card.

The camera maxes as a bitrate of 280Mbps H.265 or 600Mbps H.264, so testing will need to be done. It is possible that Sony is giving us 280Mbps at 24p taken from a 120fps source, which would mean it is dumping 1400Mbps ( 175MBs ) to 3000Mbps (  375MBs ) to the card depending on the record mode. Our guess is they use some other bitrate special to this mode as they did on older cameras.

This would produce significantly nicer image information if that is the case, and users would likely want to take advantage of it. More on this later.

For now, the price of CFexpress Type-A cards is still a little high. You may want to forgo shooting S&Q 120p footage if budget is a concern, stick with v90 UHS-II cards, and wait for more competition which will force Sony to lower their price. You don’t get sound with S&Q and we don’t know how much better it looks than standard 4k120p, yet.

Sony FX3 Specs

List of Sony E Lenses

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 | In-Camera Memory Performance Benchmarks

These tests are taken with continuous burst high at ISO 100. The buffer is filled and the time it takes to clear the buffer is calculated against the record times.

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.

What’s the difference between XAVC HS, XAVC H-I, and XAVC S?

These are actually containers that offer different capabilities, they are not codecs exactly. These containers are capable of recording 10-bit 4:2:2 with the main difference being the codecs, H.265 vs H.264.

XAVC HS allows for H.265 recording.

XAVC S and S-I still only record to H.264. The S-I variant is an all intra recording. Meaning keyframes on every frame.

H.265 offers better compression performance at a lower bandwidth which makes it a much more efficient file. So H.265 can produce almost twice the quality at a similar file size as H.264 depending on the scenes.

The disadvantage of H.265 is it is harder on the CPU to decode and it will often require you to work with proxies when editing, which is actually very quick and easy to make.

EDITORS NOTE!

Our GPUs and Processors can decode and encode H.265 very quickly with built-in hardware encoders but be warned. If you export H.265 using hardware encoding, I have yet to see AMD, NVidia, Apple or Intel use 10-Bit 4:2:2 with their hardware encoders, only 4:2:0. Do not export your beautiful film all shot in 4:2:2 with a hardware encoder turned on, only to get a 4:2:0 master. This would be bad and you may see bad information in your shadows.

You not only need to disable hardware encoding in your export interface, but also you should turn it off in your sequence settings if you’re using Premiere.

I haven’t tested Intel’s new architecture, Tiger Lake or Rocket lake. It’s supposed to be much better than anything we’ve seen before. 

All the AMD fanboy hardware channels never test for this, but Intel is usually a step ahead with some of the technologies found in their chips when it comes to encoding and they silently upgrade it every year. Research this before building your next rig.

H.265 vs H.264 What’s The Difference?

H.264 is an older codec that was used by all the older Sony cameras. H.264 will support 10-bit at a 4:2:2 subsampling but it’s not as efficient as H.265. You can still get great quality out of H.264 since Sony increased the bitrate to 600Mpbs with H.264.

This will give you similar quality to H.265 (probably still not as good as H.265 at 280Mbps) but with a bigger file size. Most computers will be able to edit these files without any issues, so you’ll have to test for yourself the advantages and disadvantages of each system. I personally just edit with H.265, using the proxies in Premiere. If I’m doing 1080p H.265, my computer handles them fine without proxies.

Sony FX3 Recording Specs & Details

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

Should You Use XAVS HS or XAVS S-I?

You should use XAVC HS with the H.265 recording when you can. You may need to develop a proxy post-production workflow in Premiere or Divinci Resolve to speed up the editing process. It’s incredibly simple to do once you’ve got it all set up. It’s worth the file size advantage and image quality advantage.

I’m currently using H.264’s as my proxy workflow, but if you want to keep 10-bit files for some better color grading on the proxy files, ProResLT is also a great choice for proxies since ProRes LT will keep 10-bit.

I have a guide to proxy editing here

If you need to get to editing quickly without proxies, you’ll likely want to shoot with XAVC S-I which records H.264. Keep in mind the file sizes will be much larger if you’re using the max quality of 600Mbps and you’ll need to use more expensive V90 cards.

Sony FX3 Record Times – Memory Card Capacity

Here are the record times for 4k bitrates based on a few memory card sizes.

Use this table to see the memory card capacity with different record settings.

What Size Memory Card Is Best?

If you’re coming from older Sony cameras that had a max bitrate of 100Mbps, you’ll quickly notice the higher bitrates of the FX3 just devour data and you’re going to need to get bigger cards.

You’ll probably want to start with a 128GB card which gives you 61 minutes when recording with the 280Mbps H.265 bitrates. This is going to be enough for smaller projects or videos that take only a few hours to shoot. 

If you shoot 600Mbps with H.264 because you don’t want to deal with the additional post-processing labor involved with H.265, then you may want to start with a 256GB card.

On long shoot days or big projects, you may either want to go with a bigger card or clear off the cards midday, which means you have to bring some sort of computer and backup drives. So this all depends on your budget and workflow.

Avoiding Counterfeit Memory Cards

Counterfeit memory cards still plague many online retailers and you can end up with them if you’re not careful.

Here is a quick guide on how to check and avoid buying counterfeit cards.

First, only buy memory cards from trusted stores. BHphoto, Adorama, etc. If you buy from eBay, or Amazon, make sure that you still select a trusted seller.

Some stores even mix inventory, so be careful about that. I haven’t had it happen when buying from Amazon personally, but I’ve heard about it happening in Europe.

In general, if you see a cheap card with a price that seems too good to be true, be careful.

How to test for counterfeit memory cards?

Counterfeit memory cards are often made by hacking the memory card controller to report a false capacity. For example, they’ll take a 32GB card, and hack it to read as though it’s a 128GB card.

Everything will work fine for days or weeks until you cross that 32GB threshold, then the card fails.

What you can do with the Sony FX3 is set the camera to record video at 600Mbps, and let it run on each card you buy until it fills the card. If the card reaches rated capacity then it’s most likely authentic. 

Best Memory Cards Sony FX3 Conclusions

Shopping for memory cards for the Sony FX3 is a little tricky since it takes two different types of cards. When CFexpress Type A cards come down in price it would make sense to just buy two of those and you’ll have a system that can handle any record mode.

For now, you may want a smaller CFexpress Type A card for some high bitrate shooting, then grab a V90 card for general day-to-day recording.

If you’re just shooting fairly casually and you don’t need that S&Q record mode and you’re fine with capturing 120p the normal way, then any UHS-II card will work fine.

The big take away would be to remember

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.