Treat it like a film camera!

If you have a modern camera that can record log or raw and has 13 stops or more of dynamic range you need to stop thinking “video” and think “film”.

A big mistake most traditional video camera operators make with these big DR cameras is to treat them as they would a typical limited dynamic range video camera and constantly worry and obsess about protecting highlights. Why do we do this? Well probably because that’s what you do with cameras with a very limited range and that’s probably what you have had drummed into you for years. But now with modern large sensor cameras everything changes. When you get to a 14 stop range camera, even if you choose to shoot 2 stops over exposed  (perhaps by using 500 EI on an FS7 or F5) you still have as much or more over exposure range as a conventional video camera and the highlight range that you do have is not subject to a knee or other similar acute highlight compression. So any highlights will contain a ton of high quality, usable picture information. By shooting over exposed by a controlled amount (1 to 2 stops), perhaps by using a low EI you gain very big improvements in the signal to noise ratio and get better saturated colors (opening the aperture lets more light onto the sensor, your colors will be better recorded). This allows you to pull a lot more information out of the data thin shadows and mid range. Most cameras that use log have very little data in the shadows. If you are recording with a 10 bit codec cameras that use variations of the Cineon log curve (Arri LogC, Sony S-Log3, Panasonic V-Log) only have about 80 luma shades covering the first 4 stops of exposure in total. Above the 4th stop the amount of data per stop increases rapidly so a little bit of deliberate over exposure really helps lift your darkest shadows up out of the noise and mire. Up in the highlights each stop has exactly the same amount of data, so over exposing a bit doesn’t compress the highlights as it would with a conventional camera, so a bit of mild over exposure is normally not noticeable.

Really with a 14 stop log camera you want to treat it like film, not video. Just like film, a 14 stop log camera will almost always benefit from a controlled amount of over exposure, highlights will rarely suffer or look bad just because you’re one stop hot, but he shadows and midtones will be significantly improved. And just like film, if you under expose log you will take a big hit. You will loose a lot of shadow information very quickly, have less color, it will be noisy and the highlight benefit will be marginal.

460x150_xdcam_150dpi Treat it like a film camera!

14 thoughts on “Treat it like a film camera!”

  1. Hello Sony!

    Any chance you are going to release some more of Alister’s excellent tutorial video’s about your very nice PXW FS7?


    1. I mean, the principle of your advice to change from Cine EI to Rec709 to record a scene with low DR I understand, but how to access the DR of a scene.

      1. It’s simple really, if the scene doesn’t have more than a 6 stop range then your wasting a lot of data using CineEI and you don’t need the additional DR, so use custom mode where you will have a better match between what you are shooting and the recording range.

      2. Hi Jim,

        I am trying to get up to speed on all this myself. Really complex some of it. I would hazard a guess that you either need experience or a lightmeter. Me? I need the meter! Bob

  2. If I am using a Rec 709 LUT in the VF am I still supposed to overexpose? If an interview subject has hot spots on their face that in my VF are blown out / are white without detail, is that okay? Will the detail absent in my VF image be there in the post prod manipulated video?

    It seems odd to me to expose so that an image looks bad in the VF and wanted detail is not there. A system by which detail is missing for the camera operator / DP on set but there at a later time obviously isn’t a good way of going about things. There could be things that the DP is unable to see due to detail not being there at the time of shooting.

    Many advise to over expose with the Fs7, but does that mean that you should always overexpose regardless of whether you are shooting log, shooting Cine EI, shooting custom, etc?? Do you recommend ALWAYS overexposing regardless of what camera settings are being employed?

    1. Please see my guide to the fS7 and the section on exposure index to understand how this works.

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