Do you really want or need 4K?

For the past 18 months almost everything I have shot has been shot at 4K. I have to say that I am addicted to the extra resolution and the quality of the images I am getting these days from my PMW-F5 and R5 raw recorder. In addition, the flexibility I get in post from shooting in 4K to crop and re-frame my shots is fantastic.

BUT: I have a Sony A7s on order. Us European buyers won’t get them until late July as the European model is different to the US model, in the US the cameras are based on the NTSC system, so do 24, 30 and 60fps while the European models are based on PAL, so do 25 and 50fps  but with the addition of 24fps as well. Right now there are no realistic portable 4K recording option for the A7s, these will come later. So this means that for a now if I want to shoot with the A7s it will have to be HD.

Is that really such a bad thing? Well, no not really. It’s a sideways step not a backwards one, as I’m getting the A7s for a very specific roll.

Image quality is a combination of factors. Resolution is just one part of the image quality equation. Dynamic range, contrast, noise, colour etc all contribute in more or less equal parts to getting a great image. The A7s delivers all of these very well. If I am delivering in HD then most of the time I don’t NEED 4K. 4K is nice to have and if I can have 4K then I will take advantage of it, but for an HD production it is definitely not essential in most cases.

The reason for getting the A7s is that I want a pocket sized camera that I can use for grab and go shooting. It offers amazing low light performance and great dynamic range thanks to it’s use of S-Log2. I’m really excited about the prospect of having a camera as sensitive as the A7s for next years Northern Lights trips. I should be able to get shots that have not been possible before, so even at “only” HD the A7s will get used along side my 4K F5/R5.

In the future there will of course be external 4K recording options for the A7s making it even more versatile. I probably won’t always use them with the A7s but the option will be there when I NEED 4K.

Given the choice, if I can shoot in 4K I almost always will. I want to shoot in 4K whenever I can. It really does give me much greater post production flexibility, for example I can shoot a wide shot of an interview in 4K and then crop in for a mid shot or close up if I’m delivering in HD. So 4K will always be very high on my priority list when choosing a camera. But if you can’t afford 4K and are still delivering in HD then worry not. It’s probably better to have a well optimised HD camera than a cheap, poor quality less than perfect 4K camera. Don’t let 4K trick you into buying a lesser camera just because the lesser camera has 4K.

Well shot HD still looks fantastic, even on a big screen. Most movies are shown at 2K and few people complain about the quality of most blockbusters. So, HD is still good enough, 4K has not made HD obsolete or degraded the quality of existing HD cameras.

But is good enough? Good enough for you and your clients? I am passionate about getting great images, so I don’t just want good enough, I want the best I can get, so I’m a 4K convert, as are some of my clients. I’m actually delivering content in 4K for many of my customers. But sometimes, 4K isn’t practical, so in these cases I’ll just get the very best HD I can (hence the A7s for very portable and ultra low light shooting).

The bottom line is that right now, maybe you don’t need 4K, but it’s OK to want 4K. You may need 4K very soon as it becomes more mainstream (some nice Samsung and LG 4K TV’s are now available in the $1.5K/£1K price range). 4K might bring you many benefits in post production, but that doesn’t mean you need it, not yet at least. But once you do start to shoot in 4K there is no going back and while you might still not need 4K, you’ll probably find that you do actually need 4K. 🙂

11 thoughts on “Do you really want or need 4K?”

  1. Thanks, Alister! A bit concerned about reports of significant rolling shutter artifacts for the A7s. Important as I’m thinking of using it on a lightweight steadicam-like device in cars and while walking for adding motion to my filmmaking. Any thoughts on that?

  2. ” Right now there are no realistic portable 4K recording option for the A7s” I’m interested to know how that statement relates to the Shogun 4K RAW Recorder option being promoted by Sony? Or are you talking about ‘on board’ 4K recording options as a future incantation.

  3. The Shogun isn’t available yet and won’t be available until the end of the year. So the cameras are shipping but there are no suitable portable recorders at this time. The Shogun won’t be raw with the A7s and I don’t know of any camera that can output raw over HDMI.

  4. Interesting thoughts on using the Sony A7s Alister.
    I have a client wanting some work doing with small
    compact cameras and so have neen looking at the
    Lumix GH4 and the A7s.
    What is your thinking on suitable lens sets for this
    type and style of camera?

    1. The lens requirements are slightly different for these two cameras. The GH4 is a micro 4/3rds sensor while the A7s is a Full frame sensor. The A7s can be used either in full frame or APS-C modes so that opens up a lot of possibilities. Plus there are plenty of adapters for Sony’s E-Mount from cheap Chinese electronic adapters ($90) to the more expensive but well regarded metabones adapters. The GH4 can be used with a soon to come metabones speed booster adapter that allows you to use APS-C lenses and that too opens up many options. For me, one key issue is the ability to use full frame lenses on the A7s with little loss of FOV. So a lens like the new Sigma 18-35mm Art lens (which I already have) should be really nice and not too expensive. In addition I can use all my Samyang/Rokinon full frame prime lenses.

      Both of these cameras have a lot of potential and choosing one over the other is tough. I think the A7s has the better sensor, but the GH4 can do 4K on-board. The HD from the A7s is really quite remarkable thanks to the use of Slog2 and the 4K will be pretty amazing once the recorders become available. I’m very excited about the creative possibilities that a high quality compact camera can bring, for example low cost hand held stabilisers, small jibs and cranes etc. Shame us Europeans have to wait until the end of the month for the 24/25/50fps model.

  5. Thanks for the lens thoughts Alister. The larger sensor A7s is sounding more interesting. I was intending to try and test the Samyang/Rokinon ciné lenses
    as I was concerned that for the price they would not really be good enough
    quality. However, if you are using them that is a sound reccomendation. My
    debate is really between the Samyangs and TLS ‘cineised’ Zeiss ZF2s. Have
    you compared these by any chance?

  6. Hi Alister,

    I was doing this math in my head and I’m not sure if I’m close here. (maybe you can calculate better than me)

    A7s with full frame lens: A 24MP sensor with a full 16×9 crop will give you about 10mp for a 4K image? (2mp more than what is needed for 4K but enough for a nice deBayer recovery..2.5 million red, 2.5 million blue and 5 million green)

    A7s with APS-C lens: A 16×9 center crop will now deliver about 6MP? This is not enough for 4k but plenty for a nice oversampled HD video. (1.5 million red, 1.5 million blue and 3 million green…plenty for HD)

    How far off is my math?

    I wonder how well the A7s up-scales to 4K using an APS-C lens? It would seem to have allot going against it with that task.

    Thanks!

  7. Your math is good and it’s a valid point. In S35mm mode it appears that the image size is 2768 x 1560, so not really 4K. I think full frame is the best way to go with this camera for full 4K.

  8. Alister,

    With this A7s, how do you feel about S-Log2 being recorded to an 8bit codec? I would expect that once you grade/curve it and get back the contrast for delivery, wont there be a huge 8bit “banding” penalty?

    I can understand S-Log2 recorded in the 10bit world because there are finer color “steps” to play with. Bit 8bit? hmmm…cant wait to try it myself.

    What do you think?

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