Sony’s A7S III reported to be the first mirrorless camera to use CFexpress Type A memory cards

Well, this is unusual, although not all that surprising. Sony likes to be different, especially when it comes to memory cards. According to a report on Sony Alpha Rumours, the Sony A7S III will be the first camera to use CFexpress Type A memory cards. It’s an odd choice, given that nobody makes CFexpress Type A, although it does make some sense.

They also say that it won’t quite be the dual card slots we’re used to. Instead of two separate slots for two separate cards, it’ll have a combination card slot of sorts, that can accept both CFexpress Type A or SD cards – although obviously not at the same time. Also, it might actually have a pair of these combination card slots.

SAR initially reported a rumour that the A7S III would feature dual CFexpress and SD card slots, but that it would be “CFexpress Mini”. At the time it did sound a little confusing, although they now say that the speculation has been confirmed by a new source stating that the A7S III will indeed use CFexpress Type A.

CFexpress Type A is actually half the speed of the now-commonly-available CFexpress Type B, which might seem a little odd, although even at half the speed of Type B, it can reach speeds of up to 1,000MB/sec – which is still far more than the A7S III is likely to require for its video bitrates, even at 4K 120fps and also much more than the 300MB/sec top speeds of UHS-II SD cards – and those higher speeds might be demanded for 4K 120fps.

Whether or not Sony really needed to go to the smaller CFexpress Type A form factor or could’ve stuck with Type B will only really be known once the camera is released and we can see it in our hands, but it wouldn’t surprise me if this was just a way for Sony to force its customers to come buy their memory from them – after all, Sony can’t not start making them. With the majority of CFexpress devices using Type B, it’s unlikely that other manufacturers will be lining up to start making Type A just yet.

A combination card slot that can accept both CFexpress Type A as well as UHS-II SD cards is an intriguing idea. If it does end up just being a single dual-format slot, that could be frustrating to those who’d hoped that they’d be able to record to two slots simultaneously. But, SAR believes that there might actually still be two of these combination card slots, with each of them accepting both memory card formats.

So, maybe you will be able to record full resolution to one card and low-res proxies to another, after all. Well, we only have five more days to wait until we find out!

[via Sony Alpha Rumors]