Clarity in darktable

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.

Hi’ @Jade_NL

I have studied your result with interest. It’s correct that the blacks are not clipped in your version, and this surprised me!
You use the exposure module in automatic mode. I have always used it in manual mode, which is the default mode. I don’t think that manual/automatic mode makes any significant difference. The real significant trick seems to by your tiny adjustment of the black level correction slider in the exposure module. I have never used that slider before but I certainly will in the future….:grinning:!

As far as I understand: Adjustment of the middle grey luminance slider in filmic is equivalent to adjusting the exposure in the exposure module. You can choose to adjust the middle grey or the exposure - it makes no difference.

darktable has many ways to do the same thing and sometimes a situation needs the one and another situation the other. Some advise: Don’t get into the habit of sticking to just a handful of modules. This is a good approach when you start using dt so one doesn’t get overwhelmed, but expand when feeling comfortable.

Correct. I’ve been experimenting with the automated mode for a few days now and technically the end-results for both are the same. I do think I like working with the automated one better though (did you see or have a look at Aurélien’s fast workflow for pros/time-constrained photographers? might be worth it).

Although technically true I cannot get good results using the middle grey slider in filmic rgb and I’m not the only one.

Aurélien is still developing filmic rgb and it might be that the middle grey slider will be removed/fixed in place/changed (don’t know how, compatibility with earlier versions might be an issue) and as you might have read in the editing moments link I mentioned in my previous reply other things might change as well. It might be considered strange that you need to go to 2 modules to do this.

Anyway: Hope you enjoy this “new” way of approaching this.

I use screen and multiply blend mode all the time…if you have a washed out or dark pic sometimes rather than tweaking a bunch of things related to exposure and contrast I simply apply a linear…strait line tone curve in either screen or multiply…so to lighten or darken and then I edit from there…multiply is awesome to bring a washed out photo back to life…blend modes are a hidden gem that i think many users over look…

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@s7habo Boris you mentioned 2 instances is your first with default settings then the one with mulitply…I did not see you mention the difference between the two instances??thx

Nothing special. In some photos multiplication blend mode “neutralizes” a little bit local contrast in medium grey area. With second instance you can correct this.

Okay so you start with multiply and then if you need to adjust that you add a second …in normal blend mode then …

Mail](https://go.microsoft.com/fwlink/?LinkId=550986) for Windows 10

Yes.

Yes…!
I think that blend modes could be an interesting topic to investigate and discuss in the forum. Which blend mode to use with which modules in which situations? And which blend modes doesn’t go well with the filmic way of editing photos?

There are many blend modes, but I have only seen the following used in “normal situations”: multiply, screen, softlight and overlay. Blend modes are apparently seldom used in the darktable universe……

I use blend modes all the time in a pixel editor (photoshop or affinity - haven’t used gimp yet). Never thought about using blend modes in a raw editor.

can you please explain this with some example pics as to when to use single instance with multiply blend mode and when to use the second instance with normal. specially when to to use which method

I am a bit confused.

:point_up:

Look at the road. Without local contrast there are few details:

Local contrast with multiply blend mode:

Picture is darker, and colors are better, but I want more contrast on the road.
Second instance, just to emphasize details a bit more:

This is simply a matter of taste, no tricks or anything particularly intelligent. :wink:

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28 posts were split to a new topic: New Channel Mixer thread… how do you channel mix?

Thank you for the hint.

I have watched the video “fast workflow for pros/time-constrained photographers” as recommended.

2.5 hours of video can seem a little bit scaring if you are time-constrained…:grinning:! But since the video consists of a lot of examples of editing you can stop or pause anytime. I can absolutely recommend the video.

All the editing is being performed with a fixed setting of filmic! No filmic slider is adjusted in 2.5 hours! All the editing is done by using the exposure module (in automatic mode) and the color balance tool (and sometimes a few others: white balance, lowpass filter etc.). @aurelienpierre is playing the darktable concert instrument for 2.5 hours, excellent and a lot of tricks to be learned.

I’m left with one question: in which situations should you adjust the filmic settings?

When you want to tune your virtual film emulsion, especially for the balance between highlights and shadows.

Hi’ @aurelienpierre

I asked: I’m left with one question: in which situations should you adjust the filmic settings?

and your answer is:

……and this is not often required? If yes, I suggest that the user manual is modified so you up front are advised to turn on filmic using your settings and not touch it again unless you have special needs.

As of now, you have to read through page 108-114 and try to digest the information. In the end, you get a suggested simple workflow, but more complicated than the one presented in your video.

By the way: you can assign a shortcut to your excellent preset by presets>shortcuts>global>styles and then click on the style you want to assign a shortcut to…….:grinning:

Thank you for an excellent video and a fine preset, works really well……

I am but a designer. Meaning I try to solve people’s problems.

Some people (like me) want a fine-grained control. They can tweak filmic ad nauseam, following the manual.

Some people want a semi-automatic way to process images. So they can use a preset, leave filmic as set, and bother about exposure.

Nothing is ever required. It’s all about matching intent and method.

AH, I knew it was possible somewhere :slight_smile: Thanks !

Yes, the channel mixer is a simple tool, at the foundation of image processing. It does exactly what the input color profile does : a matrix multiplication. As most simple operations, it is very powerful in terms of use. And yet, simple operation doesn’t mean simple to use. I don’t think you can escape some theory if you want to use it.

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Disclaimer, before I start: I’ve messed with the dt filmic module just enough to know I need to go and watch @aurelienpierre’s videos… so, I do not have specific knowledge about how they work.

But, I do know the fundamental characteristics of a filmic curve, and to me that’s important to developing heuristics regarding its use. Essentially, it’s log-like, with a toe on the left end. You play with the toe to “crisp-up” the blacks, and you play with the shoulder and central linear line to mess with the overall tone distribution. In rawproc, my tone tool has a curve plot to show one what the selected tone operator and its parameters will do to the image, and I’ve found that to be of critical importance in applying it to particular images.

For instance, my test raw for rawproc is a scene with a specular highlight (locomotive headlamp), a mid-morning cumulus-cloudy sky mixed with locomotive steam and smoke, and a triple-headed train where the locomotives sport various shades of gray-to-black. When I scale the image to fit black-white where the headlight is blown (don’t yell at me @heckflosse, I’ll get around to figuring out librtprocess highlight recovery… :smiley:), it almost looks good as-is, linear. Indeed, when I put the basic filmic on it, the steam, smoke, and cloud definition gets lost in that rather lofty shoulder headed to white. Really, I’ve found that the best curve for this image is a custom curve with two control points: one on the exact center of the line, unmoved, and a lower one drug slightly below the neutral line to pull the shadows down a bit.

So, summed up, here’s what I think is important about any tone curve selection:

  1. know what linear looks like for the particular image, and,
  2. know the transform curve of whatever tone operator you apply to move from linear.

That’s it. log, log-gamma, reinhart, filmic, custom; same two fundamentals.