How Do You Expose S-Cinetone with the FX6/FX3/A7SIII

exposing-cinetone-600x316 How Do You Expose S-Cinetone with the FX6/FX3/A7SIIILots of people have been asking about how to expose S-Cinetone, whether with the FX9, FX6, A7SIII or the FX3.

The short answers is:  So that it looks nice!

S-Cinetone has a variable toe and knee. So exposing it brighter results in not only a brighter image but also an image with flatter skin tones and less shadow contrast, overall looking more video like.

Exposing a little bit darker results in a more contrasty film like image. Faces and skin tones have more texture. There is no one optimum exposure level. A white card  could be anywhere between 78% and 88% depending on the look you want.  Typical skin tones will vary from between anywhere between 55% and 75%.

Personally I like the way S-Cinetone looks when it’s exposed with Skin tones at around 63% and white at around 81%.

See the video I on S-Cinetone on the FX9 for more details as it all applies equally to the FX9 and FX6 as well as the A7SIII and FX3. The only small difference is that the base ISO’s are a little different between each camera.

 

460x150_xdcam_150dpi How Do You Expose S-Cinetone with the FX6/FX3/A7SIII

10 thoughts on “How Do You Expose S-Cinetone with the FX6/FX3/A7SIII”

  1. Hi Alister,

    Always appreciate your work very much!

    I have a question about the latitude of Sony Slog3cine 10bit vs Raw via Atomos monitors on the A7sIII and FX3 cameras.
    So the Sony marketing campaign claims 12bit Log Raw from the Atomos. I guess this may be true for Chroma, but I wonder whether we’ve been tricker as to Luma.

    I did some latitude tests today and noticed some interesting things. Firstly that underexposure on the A7sIII is so much more retrievable. Nearly up to 3 stops in ISO 640 and -2 12800. So impressive! 😀

    However, comparing SLOG3CINE to RAW I discovered that the RAW files have an enormous amount of Noise. On the one hand, this is normal, because Slog3cine files applies noise reduction and RAW demands denoisung.
    However, the amount of noise at -1EV or -2EV in the RAW files does not correlate at all with what I’d expect from 12 Bit Log Raw material. It should be much less than this.
    Is this RAW really 12 bit Log regarding brightness?
    I don’t have the tools to do denoising on these files. Considering downloading Resolve for this. But from lots of grading experience, I doubt the underexpose recovery of RAW will look any better than SLog3Cine. That goes against what we should be getting with 12 Bit Log Raw. Arri Alexa footage has much less noise when 2 stops underexposed in RAW.
    How is this possible? What are your thoughts?
    Hope to hear back soon and kind greetings!

    1. Raw is a stream of greyscale bitmaps, there is no separation of chroma or luma in a raw recording as it isn’t a colour image. You don’t get separate Chroma and Luma until the raw has be de-mosaiced and turned into a colour image in post production. I see no reason to believe that the files are not encoded as 12 bit log as it very simple to do.

      It’s an big internet myth that you can recover more from under exposed raw than underexposed log, the limiting factor is the sensor and sensor noise, rarely the encoding. Raw might give you a few more very subtle textures thanks to the lower compression ratio and greater bit depth, but there won’t be any extra range. The sensor and sensor noise limits that and raw will never normally have more range than component log.

      -1EV raw will have twice as much noise and -2EV raw will have 4 times more noise than at the base exposure and this is no different to S-Log3. It wouldn’t matter whether it’s log, linear or power law. Every time you go down 1 stop you double the noise, go down 2 stops you quadruple it. As you start with no noise reduction with raw and everytime you go down one stop you double the noise, the apparent increase in noise will be much more significant than with log which may have been noise reduced so has less noise to start with. Noise reduction is an important part of a raw workflow, but at the moment there is no way to get ProResRaw into DaVinci Resolve so you have to transcode it first in FCP or Premiere and that largely defeats the benefits as you are adding a recompression step.

      It’s also worth considering that a conventional DCT codec like XAVC or even ProRes will do some noise reduction as part of the compression process. If you imagine that the S-Log3 has a noise level 2 after NR and compression while the raw is 4, it’s only a difference of 2. Then go down 2 stops, noise quadruples and the S-log will have a noise level of 8 while the raw will be 16, now the difference is a much more obvious 8.

  2. Hi Alister,
    Thank u for your sharing.
    I am wondering if you turn on the slog/hlg in the input setting of ninja v when you recorded s_cinetone. What is your recommendation on the setup of ninja v for recording s_cinetone?

  3. Just a quick question, as I haven’t found an answer online.
    Is there a reason Sony don’t offer a Waveform monitor on the A7siii or other Alpha cameras?
    It’s available even on some of it’s small, cheaper handheld cameras but not the Alpha range.
    Personally, I’m not a big fan of the Histogram and find using a Waveform much easier and more reliable.
    I’m using S-Cinetone a lot for quick turnaround work and using the Waveform on the FX9 is a breeze as I find it needs to be exposed lower than traditional Rec 709 to look good, so I’m not reaching 100%.
    I’ve bought the A7siii as a B Cam to the FX9 and trying to get the exact same exposure isn’t quite as straightforward as I’d hoped, especially in run and gun situations.
    Ideally, I don’t want an external monitor either as the idea for buying the A7siii is to keep it as compact as possible.
    Thanks in advance.

    1. I suspect this is simply because these are primarily designed as photo cameras and the designers don’t feel it’s necessary on a stills camera so don’t include the code in the firmware/hardware. A lot of these cameras functionality is hard coded into the custom made processing chips, so it’s often not as simple as just writing extra firmware.

  4. Thanks for the tips! What are the ISOs for the Sony A7RV? 100 & 400? Leeming Lut Instructions say to ETTR with zebras to 109+ … when you say your white card value is preferred at 81… can you elaborate on this as I’m a bit confused on where to set my zebras. What do you mean by 81%? Thx!!! (P.s. I’m not sure if I even want to use Leeming LUTs as the image looks better I think without.)

    1. I am not sure but I think the A7RV bas ISO’s for S-Cinetone are 125/500.

      I would only ever use ETTR for log and raw, not for S-Cinetone. ETTR (when shooting S-Log or raw) is great for photography where every image is unique. But for video it is less useful as every shot would need a different grade depending on how far to the right it has been exposed. Instead I prefer to expose brighter by a specific value across all the shots in a scene or project, perhaps one stop. This is where Exposure Index becomes extremely useful.

      So many people confuse the brightness of highlights with the brightness of white. They are two different things. Most highlights are not white, they will be something brighter than white, perhaps a bright blue sky, but when you reach the limits of what a camera can capture the highlights turn to white because everything is either clipped or in the cameras knee or roll off. When talking about white objects it will be things like a piece of paper or a white shirt and these white objects will generally be darker than the sky because the sky is the light source while the white objects reflects just some of the light.

      A white card will reflect 90% of the light falling on it, just as a middle grey card will reflect 18% of the light. This reflectance is a known value so it is very useful as an exposure reference. With Rec709 you would expose a white card at 90IRE but S-Cinetone is different so for S-Cinetone I prefer to expose the same white card at 81%. Expose a white card (or white piece of paper if you don’t have a proper white card) correctly and everything else in the mid range of your shot will be perfectly correctly exposed.

  5. Hello Mr. Chapman, I would like to ask you for some advice, is it possible to use the S-Cinetone curve with the B/W color mode? thank you.

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