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)

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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 ?

Academy Color Encoding System - Wikipedia ?

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

When does it make sense to use log tone mapping? For which images does this moudl make sense? I assume not for every shot.

And, where can I find instructions on how to do this?

You will get a better answer likely but as you can see from the sliders its a bit like filmic which you have been playing with so using the same concepts you can basically figure it out…

for sure the best set of videos on ART are in French and so there is likely a video by @carafife or others floating around out there…

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It’s a way to compress the dynamic range of a picture,.i.e. to pull highlights and/or push shadows. It’s similar in purpose to the “dynamic range compression” tool, or to some extent to the tone equaliser. What to use and when depends on taste…

how do you make your raw developer so much easier to use and still produce great results?