funny I would use a bit of tone eq for the sigmoid one esp for the left hillside and then overall I like the sigmoid better in this case if that change was made…I do like a bit of contrast maybe that is it when I look at it…
So nice to tackle other pictures than my own and it also gives me the opportunity to introduce a slider in more detail: skew!
Think about skew as a way of prioritizing contrast in your image. Positive skew increases the contrast in the highlights while reducing the contrast in the shadows. Negative skew does the opposite. But let me show it in images instead of words! The following three images are my try at editing your image using a strict scene-referred workflow (more on that later). The only difference is in the setting for skew: 0, 0.39, and 1.
As you can see, adding a bit of positive skew can make those highlights pop a bit more!
It is actually quite pedagogic to take a look at the histograms for these as well. Note how the right white part (the clouds) gets pushed to the right.
Skew = 0
Skew = 0.39
Skew = 1
Some notes on editing
Try to figure out how to put all your modules below the display transform (filmic/sigmoid). This is especially true for dodging and burning highlights and shadows as this operation is a simple multiplication when done in scene-referred space. I personally love to work with masked exposure for this effect and then complementing it with the tone equalizer when there are tricky edges I don’t want haloing around. This is a learning process for the whole community so I will try to help out as much as I can on the topic.
The new color balance rgb module works very well for me and it’s good to see it in use by you as well. One module that is yet to be “ported” to the scene-referred space is local contrast and I see that you correctly put it above the display transform. But, I have found that it actually works ok to use it earlier in the pipeline and I have been especially successful when applying it before adding saturation using color balance rgb. Might be worth a try while waiting for a rewrite of that particular module One more trick when it comes to local contrast is to use the parametric mask and only apply it on your highlights in scene-referred space.
Highlights are an interesting topic as we still do not have that many specific tools for editing them in scene-referred space, while also being the image feature that differs the most in editing possibilities when in scene-referred compared to display-referred!
I have a dropbox link on the FB page…with some instructions as well…
basically just unzip it where you like. I have a bat file in the directory that will run it from wherever you unzip it and will use an internal config directory in that folder so it won’t interact in any way with your current stuff…
Just take care as your xmp will not be compatible with standard versions as they don’t have that module…
EDIT so make a shortcut to the bat file by right clicking and add that to your desktop
I found the tone eq worked nicely with your module. I like the contrast in general that your module generates but usually the shadows need a bump and the highlights need pulled back so a basic sine wave spline in the tone eq was a nice fix…
First of all: The stork’s neck feathers where almost white, not somehow pinkish as in the filmicrgb example. In this case, setting filmicrgb’s “middle tones saturation”=0% and “preserve chrominance”=no helps. All in all sigmoid’s colours look more realistic for me, expecially the reds, e.g. in the color of the beak.
But if you look at the structure of the white plumage at the neck and head, filmicrgb delivers more detail imho.
@jandren thank you very much for your hints and suggestions. I did some additional image edits with the sigmoid module … and I like it more with each edit I am doing
Now I will play a bit with the skew parameter, too. I am quite sure that this is a very powerful module and for sure a great alternative to using filmic. In my opinion it should be integrated into Darktable very soon.
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.