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wswartzendruber · 10th November 2021, 06:06

Let's say I've got a HDR10 movie which grades reference white at 100 nits. Well, let's also say I want that level of brightness to be at 203 nits instead.

Right now, I'm naively multiplying linear display brightness by the required factor (203/100). This looks mostly fine, but BT.2390 is talking like I also might want to consider gamma correction here.

Now, this makes sense. The artistic difference between 100 vs. 50 nits is not the same as 10,000 vs. 5,000 nits, which would be the result of my current approach.

So how do I perform this gamma correction? I can't seem to find anything on it.

10th November 2021, 06:06	#1 \| Link
wswartzendruber hlg-tools Maintainer Join Date: Feb 2008 Posts: 413	How Do I Scale Luminosity? Let's say I've got a HDR10 movie which grades reference white at 100 nits. Well, let's also say I want that level of brightness to be at 203 nits instead. Right now, I'm naively multiplying linear display brightness by the required factor (203/100). This looks mostly fine, but BT.2390 is talking like I also might want to consider gamma correction here. Now, this makes sense. The artistic difference between 100 vs. 50 nits is not the same as 10,000 vs. 5,000 nits, which would be the result of my current approach. So how do I perform this gamma correction? I can't seem to find anything on it.