Sony’s A7s camera and the 4K conundrum – explained

If you thought 4K was big in 2013, then you ain’t seen nothing yet. With the World Cup around the corner, tech manufacturers are pushing ultra-high definition footage like never before. Mostly, in the hope you’ll buy a new TV before Wayne Rooney and co crash out on penalties again.

With the impending launch of Sony’s A7s camera, the realm of 4K seems set to expand beyond the limits of your living room. You’ll now be able to capture your holiday memories in impeccable detail, but do you really need to? We explain the 4K camera conundrum.

DSLR cameras – our test lab verdict on the latest flagship cameras

What is 4K?

4K is a new standard of picture resolution that’s four times sharper than 1080p high definition. An ultra-HD TV will have a 3,840 x 2,160 pixel resolution, meaning it displays footage using 8 million pixels. Such an huge amount of data allows for the reproduction of incredibly sharp pictures, even on the 50-inch plus screens that 4K TVs generally come with.

Why put 4K tech in a camera?

Although there are more and more 4K TVs going on sale every month, there remains a dearth of footage to watch on them. At present, no British TV channels broadcast in ultra-high definition, true 4K Blu-Ray discs have yet to launch and Netflix only streams a very limited number of shows in 4K.

One solution to this 4K content shortage is for TV owners to shoot their own video with a compatible camera. That’s why the Sony A7s and FDR-AX100 camcorder have been pushed onto the market, to help prop-up TV sales. Though expect to wait a little bit longer until traditionalist manufacturers like Canon and Nikon hop on the 4K bandwagon.

What’s so special about the Sony A7s?

Aside from its 4K capabilities, the A7s’ standout feature is a maximum ISO of 409,600. This means it can shoot high quality footage, with an acceptable amount of distortion, in near-darkness. Watch the YouTube clip above to see the function at work by a campfire.

Because of this sensitivity, the camera has a 12.2 megapixel resolution compared to the 36.4Mp resolution offered by its cousin, the A7r. Since 4K footage takes up such a huge amount of file space, you’ll need to attach an external recording device to the A7s in order to use it though. This means it’s essentially a camera for videographers, rather than photographers.

Which? expert verdict – ‘Why pay extra for something you can’t watch?’

Rob Leedham profile imageThe arrival of 4K in a camera you can actually afford is hugely exciting. In the next five or so years, I’d expect this feature to come as standard in flagship CSC and DSLR cameras. As such, Sony’s A7s is a pioneering device and I can’t wait to see how our test lab rates its footage using that incredibly high ISO range.

Is it really worth getting the near-£2,000 A7s over the cheaper Sony A7 or A7r or a £400 Best Buy DSLR though? I’d say no, certainly not right now. In a classic chicken-egg situation, getting the best out of a 4K camera requires you to get a 4K TV, and vice-versa. In short, a costly dilemma I suggest you dodge for at least a few more years.

By that time there’ll be a whole lot more 4K camera choice than just the Sony A7s, and there’ll no doubt be cheaper options too. In the meantime, seeing whether or not the A7s meets with our test lab’s approval will be very interesting. But, whatever the result, I’d suggest you’ll want to think extra hard before investing in one.
Rob Leedham – senior researcher

More on this

Best buy DSLR cameras – expert camera reviews from Which?
Compact system cameras explained – how do these camera types differ?
How to buy the best DSLR – what to look for when choosing a DSLR

Categories: Cameras

Tagged as:

One reply

  1. @Robert – oh, you’re back? Good. There’s a comment on your last post that requires you (or any of the other Which? staff who are active on here) to approve it before it will appear to other visitors. Unless, of course, you’re deliberately sitting on it? Thanks.

Create account

You can leave a reply without having a WordPress account, but if you do register you can upload an avatar. A WordPress account is not connected to your Which? login and cannot be used to login to or any other Which? services.

Sign up