New Episode: dynamic range compression 
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As always another nice one.
A challenging image and you’ve shown us, explaining your steps along the way, that it can be turned into a good edit in a few ,relatively, easy steps.
BTW: Not sure if this is at all possible from a licensing point of view, but would you be willing to post the RAW image you use in your video’s in the future?
I’m interested by your complete neutral preset. I get the same module display as yours, but from the image standpoint I don’t get the complete neutrality …
Inputs on this would be appreciated. Thanks !
Watching this video really inspired me to try out some old video which was difficult to post process. Would mind if I can share the same edit with the RAW and and the generated XMP file for reference. Some feedback will be useful to correct my post processing learning.
In this case unfortunately not, because this was a contract work, but in itself I can do it in the next ones.
Yes, that is difficult, I only know that the medium grey should be 18.45, contrast 1 and latitude 100% (= completely linear). As for white relative exposure and black relative exposure, I don’t know exactly. I guess it depends on the dynamics of your camera. But we can ask @anon41087856 what the “most neutral setting” would be for filmic RGB, where the module is on, but doesn’t make any changes to the image at first?
Yes, please. I recommend that you make a post as [Play raw], and you can also name difficulties you are confronted with, so that I and other darktable users can help you.
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Filmic can’t have neutral/no-op settings, just because it has a logarithm inside, which doesn’t tolerate zeros in RGB values, while its input can be zero. So there is always some lifting to do. The most you could do would be to set contrast = 1, latitude to 100%, scene grey to 18%, scene white to 2.45 EV and scene black to… -infinite EV.
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You mentioned something like that in your video so I figured as much for the current image. Future RAW’s would be nice, but don’t feel obliged in any way if you aren’t able to for whatever reason!
I also believe it is camera dependent. My Nikon D750 has a very nice dynamic range, and a filmic setting for that one doesn’t work too well with my lumix pocket camera.
Curious what AP has to say about it.
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Thanks a lot! This is what I wanted to know. This is a very good setup if I should explain to someone how Filmic works, and they can then visually follow what is happening as changes are made.
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This thread got a bit in-depth 
I tried to explain Filmic RGB to my wife based off of @anon41087856 videos and ended up with “basically math happens, but instead of uncontrollable curve you’ve got values you can control!” 
I’m no AP, but I think it’s not only camera dependent but also scene-dependent. Same’s with tone equalizer. The “filmic universal” settings of setting middle gray to 18.45 and then doing white/black point results in huge differences in same camera depending on scene lighting, contrasts etc.
Additionally - I think that filmic helps me to squeeze most of my camera’s DR by allowing better control. For example - I recently shared this Play Raw:
on base curve I couldn’t get jack from it (and scenes from the whole show). My photo group friends using their tools of choice had same problems too… However filmic allowed me to do way more pixel pushing and get better DR than I thought possible.
That makes sense… This combined with your post about not overexposing gives me another idea for a question: if one were to do dumb stuff with partially overexposed image, like trying to bring overall lightness down by sending RGB values into zeroes/negatives - that would make filmic not happy at all, right? That’s why it’s actually better to underexpose a bit, then push raw +1EV and start with filmic @ 18.45% grey?
Hmm… Do you think you could make some of your future Editing moments with darktable a Play Raws? Like, at the end add RAW + created XMP here with in playraw tag ad add link to it to your Youtube video description?
Play Raw is great for that! I can attest to that!
TBH - current filmic rgb presets maybe ok-ish, but presets like completelly neutral etc (non DR-based, but rather usage based) would be greatly appreciated!
Yes.
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It is definitely scene dependent!
My answer was in the context of having a general (or in my case camera specific) neutral starting point.
I’m not all that pleased with the default setting (and the presets) that filmic rgb comes with out-of-the-box as a starting point. This might still be a partial (?) lack of understanding on my side of things and/or the fact that I do start with the exposure module to set the exposure (=set middle grey to 18.45% in filmic).
I’ve tried starting with the neutral settings @s7habo shows in his latest on a handful of images (different dynamic ranges/camera’s) and am liking this starting point much better, even when I compare them to the 18.45% based presets that I’ve experimented with.
And @anon41087856 reply makes clear that we can only approximate some sort of neutral state. I do need to experiment with the values he mentions in combination with my camera’s to see if there is an even better “neutral” starting point for my hardware.
But all the above is just a starting point, things absolutely need adjusting from that point on for that specific scene!
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For me, the ideal starting point would be the following:
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exposure module with color picker (point and area) for middle gray (linear 18% gray), so that exposure module automatically brightens (or darkens) the image based on the selection.
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filmic without medium grey slider (18% should be fixed value) with “neutral” position as @anon41087856 mentioned: Contrast 1 Latitude 100% White exposure 2.45 EV and Black exposure -16 EV.
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the exposure value from the exposure module can then be added to the white exposure in Filmic to start compressing dynamic range.
This separates exposure from compression logically and makes it much easier to understand what each module does.
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I really like your idea. Especially this part:
It does make more sense logically, although I’m not yet sold on getting rid of the middle grey luminance slider and hardcode it to 18.45%. Maybe after testing/playing around with the neutral setting, be it yours or a adjusted one, for a while I find that using it isn’t needed any more. I’m not unquestionably against removing it, by the way.
Setting it to 18.45% by default would be a good start.
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@anon41087856 explained somewhere (here?) that the defaults as of now are a bit better “ux” since you start with ok-ish image, but actual good value would be 18.45%, since it makes curve more well behaved if you need tweaking.
Could you get this by using the auto mode of exposure…I would have to see what settings might allow calculation of middle gray at 18.45 %?? Not sure if percentile could be set to approximate this??
I normally use spapseed, what you have shown us is really amazing and now I really want to move to Darktable. Thanks for the effort.
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Nice! Let’s start calling it darktable. 
(I am not a stickler for such things but some are!)
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Boris in the last edit I see you moved the contrast equalizer. Rational??
Thx
I wanted to have it at the end of the pixelpipe so that no artifacts are created when other modules come after it. I often do this with other modules as well.
For example, color balance module always comes before Filmic. But if I want to make additional contrast or other corrections after Filmic, I move color balance (or new instance) over the Filmic.