3.0 How to get good results automatically?

Exactly, the mask exposure compensation does an on-demand rescaling, so tone equalizer can deal with anything at the input because the mask will be scaled internally, and the core operation is a simple pixel multiplication, so the range doesn’t matter.

Thanks a lot. This helps me to understand how to use Tone Equalizer. If I push to the right in the exposure module and highlights get clipped, my luminance histogram in the tone equalizer will be clipped as well without exposure compensation of the mask, even if I did tone mapping in filmic, because it comes later in the pipe.
Slowly getting there…

You are referring to rgb curve and rgb levels?

Yes.

Does this mean that the filmic module will process the image so that the output is never clipped?

Filmics output is scaled between 0 and 1. Whether that clips data, depends on how you set your white and black points.

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I am having some concerns, trying to process with Linear RGB and avoiding Sharpening Module. The final images tend to be a little too soft-blurred.

I hate too-much sharpening, so I don’t think the issue is my preferences for high sharpening and strong halos. That is not me.

But a Bayer raw is naturally a bit blurred. I want to fix that, only just enough so it does not look slightly blurred.

How can I do that with the Linear RGB tools?

cheers

Use local contrast module

Yes, I have been, but it seems to change the character of the image in too many other ways, not just blur reduction. I don’t always like that effect. Yes, the default LC doesn’t change the ‘look’ too much, but it barely touches the appearance of blur either. So I turn it up a bit, and … too may other aspects of the ’look’ start changing.

Maybe there is a way to use LC that clears up blur without giving a ‘cranked-up LC’ look?

Contrast equalizer? You can control the what frequencies you want to sharpen.
You can control the luma or chroma.

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That all depends on what sort of blur you want to get rid of (haze, lens, demosaicing, …). For lens blur, there is no deconvolution module for now.

Also, avoid pixel-peeping too much. Exporting a 24 Mpx raw at 4K resolution means you compress 8 input pixels into one output pixel, so evaluating the sharpness of the picture zoomed-in at 100% doesn’t make much sense.

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OK, thanks.

Contrast equaliser was suggested, and I am looking at it now. It is pretty complex — I will have to study it — but its ‘sharpen’ preset looks promising.

The blur I am keen to address is from demosaicing.

cheers

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Let us know how you go with it.

The contrast equalizer is quite powerful. I myself use it a lot for chroma denoising.

I too was looking for a replacement to sharpen and I was also redirected to using contrast equalizer (CE). I am now using routinely softer versions of the presets “sharpen” and “clarity” as straight replacement to sharpen and local contrast modules. By softer version I mean that I reduce their opacity to 50/60%. You may want to have a look at those presets.

The sharpen preset in CE with reduced opacity does very little zoomed out and you only see the effects at 100%, which is what you’re after I think.

@aadm @T_N_Args You may know but many don’t that the last dark bar sets the limit of the finest detail in a particular image that we can see and it changes with the zoom level that you are at. So any curve changes above that actually have no effect (see around 15 min in the video). Once I discovered this I was able to lift the luma curve at the edge of this bar to enhance fine detail and get some really fine sharpness. As you mention I think the presets are a bit too harsh so if I do a quick application of one I usually knock it back…also I have found bumping up the middle detail can give a nice effect as well maybe as high as the first horizontal scale mark with a lift at 2 of the adjacent markers… This is an old video but a good one for the equalizer… https://www.youtube.com/watch?v=zzVXK4eAM5E

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@aadm @T_N_Args Try to use bilateral verson of LC…often I like it better …seems sharper and doesn’t seem to brighten the highlights in the detail as does the default…in fact bilateral with a really low coarseness…and contrast produces some nice find detail enhancement…

Yes. I was using Local Laplacian LC because of M Pierre’s recommendation. But I do notice it very quickly applies an ugly ‘dark halo’ effect.

And I have noticed that Bilateral Grid LC does not do this — at all.

done - german is here: darktable 3: RGB oder Lab? Welche Module? Hilfe!

@anon41087856: Two things are unclear though:

Les modules qui travaillent en RGB linéaire et réalisent des opérations non-linéaires mais respectueuses de la chrominance (à condition d’activer le mode ad-hoc ) sont :

  1. courbes RGB ,
  2. niveaux RGB .

What does ad-hoc refer to?

Balance couleur :

  • CDL : RGB_sortie = (slope × RGB_entrée + offset)^power

What does CDL stand for?

The english version on hackmd.io is also unclear about these.
Thanks - great article, great background infos.

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Ad-hoc is latin for “designed specifically for that purpose”. RGB levels and curves can preserve the chroma provided you enabled their “chroma preservation” mode.

Colour decision list, aka slope/offset/power mode in color balance.

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Thanks for quick explanation. I added that als footnotes to the translation.