I can 100% agree on this characterization.
But it has to, at somepoint anyway. I think we are discussing where the tradeoffs should be and how they look like?! And this is where I see a huge improvement/addition in what sigmoid offers.
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What if you tone eq the cheek on sigmoid…for me the tonality of the filmic one on the face is too equalized but the sigmoid one is a tad over contrasted on the cheek… I did some matching of patches in another image and it seems like filmic needs a bit more exposure if you try to match areas in an image between the two modes… this might not be the way you would use it or edit but I found when the goal was to get a similar edit filmic needed a bit more ev ie you couldn’t just enable one and disable the other one… but as with lots of this it can be highly bias by the observer in this case me… 
PS that observation came from messing around with the pants in the image @Kofa provided of the fish float in the parade of the striped shirt gentlemen…
It works when I click on it to activate the lightbox preview. I have an idea: insert grey blanks in between so our eyes get a chance to reset.
One thing I keep on reiterating about the filmic module is that it is doing a lot of things at once. Even on default settings. I know AP and others would loathe this comparison but it is kind of like PS editing, albeit more state-of-the-art, where it is challenging to view the effect of each parameter in an objective manner. In comparison, sigmoid (and filmulator) is more straightforward. So, it is truly difficult and perhaps a fool’s errand to compare the two beyond usability.
What I can tell from the _MG_0969 samples @jorismak provided us just now is that filmic appears to emphasize local contrast/detail better than the other two methods. However, it has a least one bug (see the concrete end of the drainage pipe).
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Sigmoid seems to instantly heal my issues with branches/vegetation in backgrounds - hard to adjust hardness of the transition, too strong coloration of the branches, fiddling with preserve chrominance & reconstruct.
Left: filmic rgb with tuned levels, reconstruction, and preserve chrominance to RGB power norm
Right: sigmoid with a bit lowered contrast and bumped skew.
Filmic auto levels:
Filmic tuned:
Sigmoid default:
Sigmoid tuned:
CC BY-SA 3.0
DSC06179.ARW (23.9 MB)
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The source images are nice then you can load and use snapshot…
My comment was mainly to point out things for casual readers. 
I typically open in tabs, arrange and view them the way I like.
Off topic but for those branches you can go into the lens correction module and override TCA and then tweak a little the blue…you can make nice improvements… Rawfiner shows this as a suggested first step for tough CA esp on branches… also the initial sky treatment you see with filmic likely comes from using clip highlights…I don’t think you will see that with the new code… Nice image to experiment with …thanks for sharing it…
I spoke too soon…maybe consider sharing the raw its a nice image for testing out a few areas
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Added the RAW source
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Its got nice dynamic range and colour in the shadows on the tractor so I think its a nice test image…
Hmm… that’s not a bug, that’s some clipped highlights I missed , and i kept highlight reconstruction disabled.
Bug in the workflow. 
As a viewer, I would not know the cause unless I opened and knew what to look for in the XMP (and hence have bias against filmic).
My sigmoid version has the same issue, in case you didn’t notice.
There is just magenta in the highlights, they keep it (as they should). I disabled ‘highlight reconstruct’ because I thought it wasn’t needed. My bad.
(Another case of wrong white level for a CR2).
A comparison on a photo on which I had some trouble getting the colours right:
Old edit with filmic (v6, max RGB):
New version, swapping filmic with sigmoid (all else left the same, as I was quite happy with the immediate result):
I like the colours of the sigmoid version more, especially since it got rid of the weird green tint in the clouds, which I was unable to handle in the filmic version. Thanks to tweaked highlight reconstruction settings, the filmic version has a smoother transition to the clipped highlights, though, which I prefer over what sigmoid does there.
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A fascinating image, anyhow. Congrats, luator!
Having tried both filmic and sigmoid, it is possible to achieve very similar results, but with very different settings of colour balance rgb. Not new news but I think it may affect new users first impressions of darktable.
I would vote for steering new users towards sigmoid because it gives a pleasing result without having to do anything else. This might reduce the number of repetitive comments saying that darktable has broken their image. With a few well chosen parameters in the quick access section, then darktable really is extremely simple to use. (Pretty good already, I would just add illuminant source to the colour calibration on quick access)
I would imagine that filmic, with its more purist approach of having to add the saturation yourself is better suited to users that like to explore and read up on things and become familiar with setting up their own presets.
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Something I’ve found myself doing with sigmoid… hold onto your hats… is (in per channel mode) pushing the contrast slider up till I get the ‘punch’ and saturation where I want it, which sometimes really overdoes the contrast, then use tone eq to bring the shadows and highlights back.
It’s given a few results I really like, but I guess this is misuse really…?
It’s interesting in that it gives load of local contrast without any module ‘appearing’ to do it… it’s tone eq really, combined with the contrast in sigmoid. The last image I posted on the ‘charge your battery…’ thread is one I did like that.
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Its really a workflow decision so I don’t see any issue…TE comes before sigmoid so its not like you are feeding one or the other bad data…someone else was even suggesting using levels…now that one I am not so sure about clamping the data before feeding it to sigmoid …but maybe they are moving it after?? That is one of the nice aspects for the adventurous types , ie being able to use multiple instances and in multiple spots
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Since venturing into image processing, I have discovered that it is still true that there is no one answer to processing. While it may still be a good idea to make the first non-linear/-scene-referred decision using filmic or sigmoid, it may be wise to clean up or massage the data so the input isn’t so extreme. I am not talking about setting the middle tone, which everyone should do. Now, this may be controversial to the purists here, but it is just a matter of being practical. It is like exercise:
- Warm up? Stretches? If both, which order?
- Exercise / sport
- Cool down? Stretches? If both, which order?
Research results tend to differ with the times. Which is necessary? Which isn’t? Which order? Why not do all of the above just in case?!
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Exactly. There are many examples of filmic / sigmoid magic being worked on less-than-optimally exposed images, with amazing results (not a criticism, just an observation). And certainly it’s great to have such capabilities when they’re needed. Goodness knows I need them all too often!! Some here have demonstrated they can make these modules “walk and talk”.
But I think in practice the old “garbage in, garbage out” adage applies. Try to get a good exposure and you’ll have far less work to do downstream.
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