Thank you for your work, and the 3 images.
But, Excuse me, I do not understand!
There is no lasso in RT? Where does the image come from ? Is it an example of the goal ?
What I'm asking is a link to an image in Raw or TIF or JPG and with the settings you use ! (description of what you do, or pp3 or mip)
In a previous example of Lasso (one mounth ago) that you show, you use the inverse function for lightness.
This is not a good way to use locallab (I know there is not help in Rawpedia); the inverse function for Color and light, is only present for ancillary functions, such as creating a framing skill.
The function where inverse is truly indispensable is "blur and noise"
It is better, first with "Lab adjustments" to reduce the general lightness of -15.
Then select Locallab, "quality enhanced" or "quality enhanced + chroma denoise" (to avoid artifacts), in normal mode (not inverse).
Select the area you want, it can be largely beyond the area to be treated, because the shape recognition algorithm will only process the area of the hue/chroma/luma concerned.
Then acts on sliders eg: ligtness + 15.
If necessary you can select 2 control points, in the same area.
Act on scope to select the best hue / chroma / luma and adjust with transition...
I do not say that the lasso is useless, but:
1)It's a very big job at the GUI level
2)the algorithm will be completely different.
3)Other software such as "Nik software", do not use lasso