Clarity in darktable

I removed the local contrast step from my previous reply and played a bit with your multiply variant. Didn’t even put too much effort in and the result is already much better:

Not one you can blindly use: You do need to play with the settings to get a good result and not all images are eligible. Reading the replies it seems that the latter is encountered by others as well.

That’s what you’ve got to love about darktable (post-editing in general?): No such thing as a one-size-fits-all solutions.

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I just did a noob investigation why multiplication blend mode works in some cases and found out that besides Local Contrast Module you have to change (increase) the contrast in the respective areas to get a pleasant result.

Here are a few examples that I tried using RGB curve. I applied these curves after the Filmic and then Local Contrast Module:

I came to the conclusion that the Local Contrast Module should have something like 3 additional controls according to this scheme:

  • Position is the position in the dynamic range where this additional contrast should act.
  • Range is the size of the selection for this contrast
  • Contrast is the strength of contrast.

This is of course only an observation now. Whether such a thing is realizable is another question. :slight_smile:

Position + Range = parametric selection on lightness or similar
Contrast/strength = opacity

You mean using Color balance module? Lets try that…

It works somehow, but is not easier than with the RGB curve. Feathering and size are difficult to estimate.

Is this looking a bit like the filmic curve? Except that in filmic the central part is a straight line.

Filmic curve is not comparable with RGB curve. Vertical Axe in Filmic is the dynamic range of the target color space and not the brightness as in RGB curve.

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Looks like a good topic for a video :wink:

This said, I know that light grey frame is good for editing, but when I watch a video it’s harder to read what modules you use.

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Hi’ @s7habo
Thank you for your interesting posts.

I’m surprised that you are able to get such a milky look that needs a boost of the contrast by means of the rgb curve. I have a hard time reproducing similar situations. Look at the screen shot below. I don’t think the image needs additional contrast.

Yeah, with some pictures it doesn’t make sense. Move highlights and shadows completely to the left (switch off)

And why does the picture look so HDR?

Moving highlights and shadows to the left doesn’t make a lot of difference, almost no difference.

I had hoped you could tell me why the image looks so hdr. I’m just trying to reproduce your results……:grinning:!

Below you can see the photo straight out of filmic. Looks ok, I think.

Exactly. Image has enough local contrast. Nothing more is necessary here.

In other situations, I have noticed a loss of contrast in the output from filmic, just like you do. You have demonstrated how to deal with this problem. Thank you!

Another issue: In some situations filmic outputs heavy and clipped shadows. How to deal with this problem? The tone equalizer has a hard job to fix the shadows but you could also use the screen blend mode in filmic to make life easier for the tone equalizer.

What do you think?

I haven’t noticed anything like that. Do you have an example?

Well, there is very often some clipping in the shadows and the problem is described in the user manual. A quote form the manual (filmic RGB section):

“The black relative exposure allows you to choose how far you want to recover lowlights. Contrarily to the white exposure, it is not always possible to completely avoid clipping the blacks.”

It’s not that easy for me to find a very convincing example but try to have a go on the image I upload here. I also upload screen shots with and without the screen blend mode……


DSC_0365.NEF (28.8 MB)

Are you using the exposure module too or just the filmic rgb module?

I grabbed your example image and the following is only the exposure and filmic rgb module on top of the 8 default modules (I do not use the base curve):

As you might have noticed I do not use the middle grey luminance slider in filmic rgb. I set it to 18.42% and never touch it again.

I like to get the blacks as good as possible and the main subject to middle grey using exposure and than use filmic to produce a base that is solid enough (no clipping in output/histogram) and gives me some wiggle room to continue with the more artistic modules.

“Flatness” after using exposure and filmic rgb might not always be avoidable but this can be solved with other modules afterwards. Then again, it might also partially be my lack of experience 'cause it starts to happen less and less…

Just in case: loss.contrast.filmic.nikon.d7100.nef.xmp (5.6 KB)

I personally want to see way more from the foreground tree as well …

sidecar is here …
DSC_0365.NEF.xmp (5,9 KB)

I always underexpose a little bit, so I correct this with an exposure-module-preset. Otherwise I used only filmic in the example.

I’m not an expert, but it seems to me that your procedure of setting the middle grey to 18.42% and never touch it again is not according to what the user manual describes or the guidelines of several videos on the subject. As I understand it, 18% middle grey and white relative at 3.45 is a recommended starting point for further fine-tuning the sliders in the filmic module.

I personally like to see more of the foreground trees as well. Actually, I like your version a lot. I note that your middle grey is as low as 4.50% and that you have some clipping of the blacks mainly due to the contrast equalizer and some caused by the local contrast. The clipping is shown here:

There are a few ways of dealing with the filmic rgb module. The way you mention is one and the other is the way I approach it.

I did get the impression that you didn’t and wanted to point it out to you as an alternative. As you can see in the image I posted I do not have any problems with the blacks and I am all but certain that this is due to the 18.45% and use exposure approach.

Aurélien mentions setting middle grey to 18% many times in his replies. Here are 2 of them: one, two

Others also started using this method of working with filmic rgb. Boris Hajdukovic, starter of this topic, is one of them. This editing moment and the few replies after it might be worth your time.

And there is this topic about Filmic RGB defaults

Don’t get me wrong: I’m not implying that this is the way of working with filmic, it is just one that seems to make the most sense to some (more and more?) of us.

In the end it is all about finding a way of doing things that works for you and gives you good results.