I'm pretty sure there is tone mapping/color grading functionality in Unity at this point. If you used a color adjustment layer, you can add that as a post effect.
Unreal implemented the use of LUT adjustment, so you can modify a screen capture in post, and then get the direct results back in the editor. I think Unity might have something similar.
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some quick searching found this
forum.unity3d.com/threads/intr…Seems like someone actually got it working.