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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I have noticed that you don’t have base curve and also no filmic but have channel mixture, can you please explain, so the first instance of local contrast is with blend mode multiply? And second normal?

Exactly. The base curve processes the photo too much. It is used to imitate approximately the look of the JPEG file produced by the camera. I prefer to keep control over contrast and brightness myself.

The dynamic range of the photo is narrow enough. There is no need to use Filmic to compress it.

Here you can see some examples why:

Yes. I don’t think the order is important. Just try it yourself to see if there is a difference.

I am a subscriber of your channel and have seen it before but here also I have questions regarding using channel mixture with blend mode in some and not in others. Would appreciate if you can explain your edits with it in more detail, are you tweaking the R,G,B channels visually for a look? as CM is a mysterious module! till date I thought it is useful for B&W conversation only.

That is the basis.

If you select Target to Gray in the Channel Mixer, you can then use sliders of the respective color channel to mimic analog color filters used in black and white photography.

Here is an example of red filter:

Blue in the image (sky) becomes darker, red becomes brighter.

Here is an example of blue filter:

Blue (sky) becomes lighter, green becomes darker.

Green filter:

Green is getting brighter.

If I now only want to influence only the brightness of the image without losing colors, I use lightness blend mode and the result is for example like this (red filter):

Here is the original for comparison:

You can also influence the color mood of the image by selecting one of the color channels as target and much more:

This is a very powerful tool and is not specific to darktable. Every better photo application has it, and if you want to know more, check out the countless tutorials and information on the internet.

Channel mixer is part of the basics of photo processing itself.

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In some of your examples you use filmic and in some you don’t depending on the dynamic range of the photo…… Interesting, I thought that you always needed to apply some sort of curve (base curve, filmic or a manually adjusted tone curve) to lift the luminosity of the midtones in the rawfile and to introduce some sort of s-curve, pronounced or subtle…… But that is not the case.

Yes and no. If you do not need to compress dynamic range, you can use Filmic to get a “filmic” look (compression of shadows and highlights) - typical for dynamic range distribution of analog film. And that is definitely better than base curve.

What bothers me is that this causes loss of local contrasts in these areas and I have to correct this later.