For my FX30, I've been using Lexar Gold series CFexpress Type A cards (160GB) and they're rock solid. Expensive compared to SD cards, but worth it for the reliability when shooting 4K 10-bit. The camera has dual slots that accept both SD and CFexpress Type A, but I'd recommend the CFexpress for anything above basic HD recording. Sony's own Tough CFexpress A cards work great too, but they're even pricier.

Honestly, the biggest thing people overlook with the Sony FX30 isn't just the write speed while you're filming, but the offload time at the end of a long day. If you're shooting 10-bit 4:2:2 in XAVC S-I, those files are freaking MASSIVE. I’ve been using ProGrade Digital CFexpress Type A cards for about a year now, and while they're pricey, the time I save dumping 300GB of footage via a dedicated Sony MRW-G2 Card Reader is worth every penny. For management, I ALWAYS run dual-slot simultaneous recording. It's basically cheap insurance against card failure. I usually carry four 160GB cards for a full day of production, which usually covers me unless I'm doing a ton of 120p slow-mo. Also, a pro tip: don't just look at the card speed; check your card reader's interface. If you're using a cheap USB 3.0 reader, you're bottlenecking that expensive CFexpress card anyway. I mean, why pay for top-tier speed if you're gonna wait three hours just to see your dailies? It just makes the whole long-term workflow so much more fluid, you know?

Definitely go with CFexpress Type A if you plan on doing any high bitrate work or All-I recording modes. Yes, they're more expensive than SD cards, but the speed difference is night and day. Sony's own CFexpress cards work great, though Lexar and ProGrade are good alternatives that cost a bit less.

Bump - same question here

Honestly, my experience with cards for the FX30 has been pretty frustrating lately. I tried to save some cash by using my older V60 cards, but unfortunately, they just couldnt keep up when I needed to shoot in S&Q mode. The camera would just stop recording mid-take. It was definitely not as good as expected, especially during a client shoot where I lost about five minutes of footage because of a buffer error.

• My first set of cheaper SD cards had weird mounting issues and kept erroring out.
• The budget CFexpress I tried next actually got so hot it gave me a warning on the screen during a long interview.
• Even my current setup sometimes feels a bit finicky depending on which port I use on my hub. I really regret trying to cut corners at the start. I ended up spending way more on affordable options that failed me than if I had just bit the bullet and bought the high-end stuff from day one. Compatibility is such a headache with this camera sometimes...

I shoot mostly 4K 60fps on my FX30 and found that V90 SD cards (SanDisk Extreme PRO) work fine for most scenarios, saving me from investing in CFexpress initially. Just make sure whatever SD card you get is at least V60 rated, preferably V90 for the higher bitrate codecs. If you're planning to use All-I recording or the highest quality settings, you'll want to go with CFexpress Type A though.

This is exactly what I needed to hear. Youre a lifesaver honestly.

So it sounds like the consensus is basically CFexpress for the heavy All-I stuff and SD for the more casual shoots. I've been doing a bit of digging into some performance benchmarks lately though, specifically regarding how these cards handle *sustained* write speeds over time compared to their peak ratings. I'm not totally sure on this, but I think I saw some tests suggesting:
- Thermal throttling can actually be a factor during long recording sessions even if the card is technically fast enough.
- IIRC, some cards maintain a much more stable write-curve during those long 4K 120p sessions than others.
- Someone told me that the way the camera handles the buffer can vary slightly based on the card's internal controller, not just the raw V-rating on the sticker. Honestly, it’s one thing to see the numbers on the box, but another to see how it performs when the camera's actually getting warm. I mean, the FX30 has that internal fan which helps a ton, but the card itself can still get pretty toasted. Just something to keep in mind when you're looking at those 'real-world' tests!

CFexpress Type A is definitely the way to go if you're shooting high bitrate stuff. Yeah, they're pricier than SD cards, but the write speeds are incredible and you won't have to worry about buffer issues. Sony's own cards work great but Lexar and ProGrade are good alternatives.