New Sigmoid Scene to Display mapping

With @jandren’s explanation I’ll give skew a chance, too :wink:

I bet a couple of turns on the scroll wheel in the tone eq on the neck will bring back some detail…Its just exposed more in sigmoid it seems in the highlights…

Hello.

I left this image here for your test. It’s all yours, hope to see the results using the Sigmoid module.

Creative Commons, By-Attribution, Share-Alike

This is the .jpg directly from camera. I shot the jpg using a modified Fujifilm recipe.

DSCF7042

DSCF7042.RAF (48.0 MB)

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Test it on

Note that it seems the pink cast was present even before filmic:
With exposure and filmic:
image
Without:
Screenshot_20210518_075131-4
With exposure and filmic turned back on, but no saturation boost in filmic:
Screenshot_20210518_075645-1

A filmic-based rendering (history in the jpg), with highlights neutralised in color balance rgb

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Thanks @kofa, imho your examples confirm that the pink becomes visible / disturbing with filmic switched on. And, yes, this effect can be reduced if you switch off “saturation boost” boost (I called it “middle tones saturation”). Filmicrgb in the hands of an experienced user is very flexible and fine-tunable, no doubts.

The point is, that sigmoid doesn’t need this tweak at all to show more natural colours.

I merely wanted to point out the filmic was not ‘distorting’ or ‘inventing’ colours: those feathers were pinkish even before you reached filmic. I don’t doubt that it was easier to reach the desired look with sigmoid (which is something I really anticipate having in darktable), but that seems to come from sigmoid desaturating highlights more, which may affect other pictures adversely.

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Here’s what I get. All standard settings, no tweaks, highlight clip indicator on:

original, no tonemapping
Clipboard01

filmicrgb
Clipboard02

sigmoid
Clipboard03

To be fair: filmicrgbs result without the annoying :wink: clip-indicator looks absolutely ok imho:
Clipboard04

Edit: upload correct screenshot #4

Got it :grinning:

What is the point of not making any adjustments?

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What are the (rufly) settings? More than just Sigmoid I guess. Very nice and crisp edit!

You can just use the jpg as a side car and load it to be honest I don’t remember…I do like the deblur presets in the contrast eq and you have to make some judgments about warmth a bit here. Also my export here I find are not exactly as I see them in DT but not too bad…some local contrast…let me know if you need the xmp I will see if I can find it but as I said you can just load it from the jpg…

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In this special case for my taste no tweaks are needed to deliver a sound starting image, independently which tonemapper you use. Both are doing a good job.

Very nice edit @kofa.

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Nice example @pass712!

The problem is that the feathers are very bright in this picture compared to the grass, relative to how much variation they have within themselves. Remember that both the sigmoid and the filmic modules are global tone mappers. That means that brighter pixels always will be brighter and no local adaptions are made, i.e. we have to put in some manual work here.

I had liked to begin with showing a simple exercise for figuring out where your middle grey is. Crank up the contrast setting in the sigmoid module to something that looks ridiculous and then adjust your exposure such that your subject isn’t blown out or pitch black.

Exposing for the Stork

Stork_02

Stork_02.cr2.xmp (24.2 KB)

Exposing for the grass

Stork_03

Stork_03.cr2.xmp (24.6 KB)

So there are details in there and the sigmoid module is also robust for these kinds of large exposure changes. The key to success is basically to reduce the exposure difference between the stork and the grass and the tone equalizer is pretty well equipped for doing that if you first fiddle around a bit with the masking settings. Adjust the sigmoid contrast to something reasonable and fine-tune the saturation just a bit and you can get the following for example:

Stork_04

Stork_04.cr2.xmp (31.8 KB)

Possible extra work would be to add local contrast to bring out the feathers even more (I felt like this was good enough though) and playing around with the saturation of the feathers. Mind the feathers though, most animals are dirtier than we imaging once you look closer :wink:

There is one more thing that can be done to improve a picture like this and that is paying attention to the time of the day and weather when photographing. Getting images good SOOC might seem like bullshit but making sure that the light is “good” also simplifies our raw editing after the fact. Having a bit more directional light would in this case made the feathers pop more just from how they were lit and we could thus have managed with less usage of the tone equalizer.

I hope this was helpful!

@difrkaguilar that is a very nice picture indeed, don’t know what I would do differently with it! Can I just ask what you feel about it? Are you sharing it because you want to reproduce that particular editing result using darktable or is there something you do not like about the Fujifilm edit that you had liked to improve upon in darktable?

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How much does white balance influence the result here? the scene is very green, so I’d expect a bit of magenta in the non-green parts due to that, esp. on auto WB

In my Fujifilm X-H1 I have set the MGA Leica Like V2 recipe

Yes, the main idea is to reproduce this Leica Like recipe of the JPG in the RAW using darktable.

I always shot in RAW+JPG to have a reference of the result I like. But as the RAW file have a lot more information in dynamic range than the JPG I use darktable to tweak and process it to get better results with more contrasted and vivid images.

I use darktable in scene-referred mode, and process the images with exposure 1.2 EV (for Fuji RAF).
the CAT and FilmicRGB to tweak the dynamic range. But I have seen good results in all those images using Sigmoid and I liked to see the results with one of my images. By the way it’s great.

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Absolutely! Thanks for your detailed answer.

While testing sigmoid I feel that using the tone equalizer to crank up shadows or turn down highlights together with sigmoid is very effective. With filmic you have to be very careful not to overdo it, if you don’t want to loose contrast in this areas. Sigmoid seems to be a bit more forgiving in this respect. Maybe this is due to sigmoid’s more contrasty standard setup.

Anyway, thanks for this module.

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