LOG tone mapping [Solved]

Hello @aggrigio How would you define the behavior of this tool? How would you explain how this tool works and how it differs from Darktable’s Filmique?
Capture du 2020-03-06 11-51-02

Some of if was discussed here:

My non technical explanation would be that:

  1. It’s only the tonemapping part of filmic
  2. Look is achieved with other tools. For instance tone curve.
  3. Desaturation of blacks/whites can be done with the saturation curve of the tone curve tool.

Cool! This confirms the assumption I had made elsewhere. So the log encoding only “maps” the tones by placing black point and white point and estimates the average gray from a target at 18%. For appearance, the tone curve does the job and the color curve adjusts them. Correct?

mostly correct, except the above.you specify the source and target gray (the source can be guessed automatically, but that’s just a heuristic)

1 Like

Yes of course this tool cannot work miracles. The gray must be readjusted if necessary but overall its choices are rather good especially on tonally balanced images

In darktable, this is partially done by the “unbreak input profile” module used in “logarithmic” mode. Filmic was built from that module by adding a curve on top and an exact grey mapping to display space.

In darktable, you can reproduce it with filmic if you set the curve contrast, in “look” tab to 1, and the latitude to 100%. Not sure what the regularization does though.

It improves the local contrast especially in the highlights (well this is where I find it most effective)

(qui vient d’ACES)

What does mean A.C.E.S ?
@agriggio

https://en.wikipedia.org/wiki/Academy_Color_Encoding_System ?

1 Like

Thank you! I had found many acronyms but not this one :+1: