D-Cinelike HDR LUT for DJI FPV Drone

I reverse engineered the D-Cinelike tone mapping curve (used by DJI FPV drone) using 129 sample points, and created a ridiculously precise LUT (65536 point curve) that maps the footage back to linear, for easier color grading.

Download HDR version of the LUT:
https://drive.google.com/file/d/1p-5d95vgDTge6k7lloBzHC7iJqBFv4mk/view?usp=sharing

Here is an example flight that I graded to look natural using this LUT as a starting point: https://youtu.be/HiHjOH7SE2s

The transformation in this LUT does not have OOTF. This means that number of nits that camera saw in real life will be exactly proportional to the number of nits that the HDR screen is instructed to show, and it will become exactly equal if multiplied by a correct number (gain value), and the exact number depends on your camera exposure settings (iso and exposure time). Note that this will result in a washed out picture, especially noticeable in bright scenes, and if you do happen to match nits 1:1 by multiplying correctly, any daylight will burn out and clip unless you have 10 000 nits HDR display from the future. If you instead want to use OOTF which makes the image appear more natural, then use SDR version of this LUT and apply the srgb to Rec.2100 ST2084 gamma transform using Color Space Transform Effect. See pages 11, 12 and 13 in the official HDR specification document for details and explanation of OOTF: https://www.itu.int/dms_pub/itu-r/opb/rep/R-REP-BT.2390-10-2021-PDF-E.pdf

Step by step tutorial how to correctly use this LUT in Davinci Resolve: https://imgur.com/a/2jN3FfJ

Using Davinci Resolve, this LUT does NOT work correctly by default. You need to first bypass color management on the clip (or turn it off for the entire project). Then you need to add a Color Space Transform effect to the node and set input color space to sRGB, because this LUT only remaps luminosity (otherwise it couldn't be precise enough), and since SDR and HDR use different color primaries, this step is required to get realistic colors.

In this HDR version of the video I increased saturation from default 50 to 65, because D-Cinelike desaturates footage more than reality even when using +3 saturation in drone camera settings. This becomes painfully obvious in HDR, so I opted to increase saturation to make the overall comparison more realistic.

In this HDR version of the video, linearized footage is compared to default one. That "default" one is produced by also bypassing resolve color management and using srgb-to-PQ-1000nits LUT that I created as well, which can be downloaded here:
https://drive.google.com/file/d/1NiaU4LlcMxm0MxpormDcu4-4gDxf_3lc/view?usp=sharing
Otherwise the comparison would not be on even ground. (And of course in combination with fixing primaries as described above.) I did it this way because it was the only way to get linear light output all the way from photons hitting camera sensor to nits displayed on the screen. And that is not possible using davinci resolve color management tools or the color space transform node, as they seem to be designed to produce aesthetically pleasing results, rather than mathematically correct ones. If you prefer to use the HDR defaults and davinci color managment, then I suggest using SDR version of the LUT inside of HDR project. I find that 10% of the time, this makes the grade easier for me, but in the rest of the cases I find it easier to grade bypassing color management and using my HDR lut.

srgb-to-PQ-1000nits LUT can also be used on linearly developed raws from other cameras to achieve linear and even 1:1 relationship between real life nits and on screen nits. This workflow helps to achieve natural looking highlights in HDR, compared to having to eyeball it.

Download SDR version of the LUT:
https://drive.google.com/file/d/1y50knx5XCBAr4257iGhuKGNGN9kq1bHS/view?usp=sharing

SDR comparison video that also features a short making-off:
https://youtu.be/MRVERoeqhDM

Видео D-Cinelike HDR LUT for DJI FPV Drone канала Eagleshadow