rebooting color balance

Ya I just didn’t think it would be needed like that for every image…I asked on another thread and he replied hang on …so he may be up to something…

I choose the simple tone curve preset and get this

image

There is a small change in the image and the histogram…not sure why.

I’ve just been experimenting with the medium preset that has this curve…

image

Then I am just using the mask exposure comp to move the histogram into the right contrast range…seems to work sort of…

image

I guess the middle of this would be a bit like the fulcrum and the curve would be the roll off??

image

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Exactly.

Then we could have a GUI helper slider that enlarges or reduce the lobes width around the ground level. Beauty of having a general framework is, again, to be able to specialize it later.

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That would be awesome as you seem to be able to dial in some nice rich contrast without going overboard. And then you will have a format that you could add the the quick access as well…As always thank you for your comments…

I am using darktable-3.5.0+1170~gb428b0d7f-win64.exe, and I don’t see any changes in image or histogram either.

Is it possible to get the new color balance module in a Windows build?

I thought you would have it in that build…type rgb in the search and it should come up…maybe you need a bit later one…as for the tone eq see the short attached video…its not big deal but there is some calculation applied as the histogram shift a bit when you enable and disable it…all corrections are visibly set to zero…

Doh!

Thanks, Todd. :+1:

I see, nice.
One thing - the overall brightness seems to increase quite a lot as purity is increased. I find I’m decreasing exposure to compensate, somewhat iteratively with the purity sliders. Is it possible or appropriate for Color Balance RGB to sort of “normalise” the brightness to some extent?

You are correct. I switched back and forth too quickly, and the histogram hadn’t shifted yet. Once I paused for a moment, I saw the shift. Interesting…

Its no big deal …just a curiosity…

Think about it : pastel colors, in painting, are achieved by mixing white with some colorful paint. So it’s only natural that “pastelling” colors yields higher luminance. Luminance is a component of color as much as chroma or hue, even though we have taken the habit of fully separating chrominance (so chroma + hue) from luminance for the sake of independent parameters. But adding luminance is the only way to desaturate colors to pastels instead of greys at same luminance.

If you want to avoid blowing up your highlights, you can simply use the shadows and midtones sliders instead of the global ones.

The module does gamut clipping at constant hue and luminance to the bounds of the working color space, so it is possible that what you see when you simply enable the module is just that.

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The two prominent peaks are the green of the grass and the bright blue sky. By dropping the brightness of the first and increasing the latter, I can increase the contrast between them.

As a DT noob just learning, I think this is brilliant. A very clear example like this would be wonderful in the module documentation.

I did consider this, but nevertheless thought the image was getting rather bright. I might be expecting too much, perhaps seeking the look of that Eduardo Escarti picture.
Here’s a “straight” version of a shop scene followed by my pastel attempt. If anyone can improve on the latter, that would be great.

02837-greengrocer-shop-Mere-straight.txt (36.3 KB)
02837-greengrocer-shop-Mere-pastel.txt (36.3 KB)
02837.CR2 (70.8 MB)

It might be subjective to target it…ie how far to push…
I get something like this if you do default scene workflow
filmic auto white and black…CC with picker on the gray pale…

And this is with a sort of pink color in colorize filter blended in hue …

You could do many versions of this with different hues and opacity

02837.CR2.xmp (33,5 Ko)

(I kept all the steps in history).

Or a more muted variant :

02837.CR2.xmp (34,9 Ko)

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For comparison, the result of a pure “chroma” approach (usual “saturation” setting at constant luminance) :

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image

@priort: I tried getting your xmps from the jpgs without success. Not there, newer version of dt?

If I still have them I will

I should check I have not changed setting…I do have a recent build??