dinasset,
I had made a first answer quite long today (but without the images because having to leave the PC) and I do not see it..would I have forgotten to click on "submit"?
Since it took me a long time to write it and it's late, I'll resume tomorrow.

That's OK for me. Thanks.

Bonne nuit

Dinasset here I am again
Among the tested images, here are 2, free of rights
https://www.cjoint.com/c/IBjhHoRf8r4
https://www.cjoint.com/c/IBjhEJM8cY4
and here are the upper layers obtained with the values 3300/256 (but I also tried 0 / 200.0 / 100 ...etc)
https://www.cjoint.com/c/IBjhZR2CdE4
https://www.cjoint.com/c/IBjh1vu7m04
I find that the effect obtained is hard and not harmonious (it's subjective ...)
I tried to improve then with G'Mic filters but the improvement obtained with some filters removes the effect of Look Lines.
I also tried to change in some places the orientation of the lines with tools of transformations of Gimp on selections.I had also considered applying the effect on only one selection of the source image so as to reiterate on other selections with different parameters but it does not work.
In short I spent time looking and would be very happy to know how to improve the image obtained when the effect is not satisfactory (I am still level 0)

Thanks, I will do my investigation and let you know.

Before any other trial, one question:
- I see that the Berlin Cathedral outcome shows an image (canvas) size greater than the layer size; is this something which happens to you often when using the filter? or is it just the image posted for me that has this strange behaviour?

My first attempt on Berlin Cathedral.
(Yes, as you say, the standard outcome is not nice).
What I did:
launched the filter with the parameters:
- size 3300
- colours 32
modified the outcome (unflattened) as such:
- off visibility on the top layer
- changed the mode on the before-last layer (BG on top) to HSV_VALUE
- increased the opacity of the same layer to 95.0
Here my outcome (copied and flattened):

Is it something you can evaluate acceptable?

A similar procedure for Autumn:
(again, as you say, the standard outcome is not nice).
What I did:
launched the filter with the parameters:
- size 3000
- colours 28
modified the outcome (unflattened) as such:
- off visibility on the top layer
- changed the mode on the before-last layer (BG on top) to HSV_VALUE
- increased the opacity of the same layer to 98.0
- copied and flattened
- then reduced saturation (-30)
Here my outcome:

How do you evaluate this one?

For the Autumn I prepared a second attempt:
- everything as for attempt nr 1 except that the layer mode of the BG on Top was set to PinLight and the saturation was left unchanged (hence the procedure is simpler).
I like better this outcome.

yes it happened several times

beautiful, I take note!

It looks strange to me, I used your source image too. (?!?) Can't find a fix.
After those tests, and having asked also Issabella -the best interpreter of my filters- I prepare a version which will set by default the mode of the BGonTop layer to PinLight.
I'll sends it to you.

Next time, I will note everything precisely.I have done so many times from the same source image ... and I did it from the image in jpj and also in png because if I remove the metadata with Xnview, I then record in png.


it's true, I agree

For #207,I do not see the effect of the filter ...
pour #208,super on branches, on the first tree trunk (among others) and for all colors

Yes, I noticed too for #207, that's the reason for my second attempt. The new version will have the mode set to PinLight.

thank you dinasset for having studied my problem!

And that's my opinion too I already said it a hundred times, I think ...

Ella, if you like to get the new version, prepared after the tests on level_0 images, just tell me.

(there is the change on BGonTop layer mode, but I know you like to do your changes yourself, usually).

Diego, you may send it, but yes, also in the precious outcomes I made my own changes
Not completely satisfied about them ... Just find the right picture, Issabella has the art to find it

Dinasset, Level 10 and Ella, thanks a lot for your nice comments.
I see so good results there in Lines Look.

Playing with this nice filter that Level 10 has set in trend.