Selective shading

[rickk]

In the attached picture of wire ribbon matting, there is a shading effect that I guess was intended to simulate texture by the original artist. (the diagonal banding)

Is there a process in gimp to selectively darken the light spots while selectively lightening the dark areas, with the ultimate goal of achieving a uniform appearance? I've been playing around with alternate "dodge and burn"  processes from a brush set larger than the overall image, with mixed success.

My gut feeling is that if I keep at it over and over long enough, I will eventually luck into an acceptable result. But knowing you folks are far more skilled than I, got me to wondering if there might be a better way, less depended upon random chance, that is repeatable,  which  one of you might share?

https://i.imgur.com/QZFqcVM.png

---

Here is the likely original used to make the above composite.

https://i.imgur.com/oYlIkex.png

[Blighty]

An alternative to playing around with lightening and darkening. Start from scratch and make a pattern.

Attached is a file pattern.png Put that in your patterns folder (or use it as a clipboard pattern). Then bucket fill with the pattern. Add a background with the colour of choice.

Attached is the xcf file used to make the pattern. Note the active selection. Use Edit > Copy visible to extract the pattern.

[Ofnuts]

You can sort of reduce the bumpiness like this;:

• Filters>Enhance>Wavelet decompose
  
• Starting from the bottom (Residual) replace layers in the composition by their average (Filter>Blur>Pixelize and use a block size that is at least as big as the layer).
  

For instance, decomposed to 7 levels, and averaging Residual, Scale 7, and Scale 6:

   

[Krikor]

Just an idea, although my result is not a good example. 
https://imgur.com/9QH57wD
Select an eligible pattern within the image, in order to decrease the unwanted contrast and  then create a new image using this new patttern.

[rickk]

Thanks for the suggestions, each of you!! I am particularly grateful to ofnuts, for providing a solution that I can use on pictures where I have no control over their composition. (sometimes you see a great picture, with really poor lighting, stuff like that)

I photograph a lot of wildlife, and unfortunately they refuse to pose. Many many "great" moments captured, on the wrong side of the sun.

[Ofnuts]

(03-09-2021, 04:58 PM)rickk Wrote: Thanks for the suggestions, each of you!!  I am particularly grateful to ofnuts, for providing a solution that I can use on pictures where I have no control over their composition. (sometimes you see a great picture, with really poor lighting, stuff like that)

I photograph a lot of wildlife, and unfortunately they refuse to pose.  Many many "great" moments captured, on the wrong side of the sun.

The technique can even out the lighting (fairly efficient when you take a picture of a document, and end up with one sight lighter than the other) but isn't a panacea against bad lighting.

When I shoot wildlife, I take the other approach... I search animals where they can make good shots. No time wasted making unusable pictures :  When the sun is low if you have it in your back your prey doesn't see you in the blaze...

[rickk]

Krikor,

Yeah, I kinda wandered down that path too. Here is a desktop that resulted from that effort.

https://i.imgur.com/uBWWaOB.png

[rickk]

(03-09-2021, 05:07 PM)Ofnuts Wrote: When I shoot wildlife, I take the other approach... I search animals where they can make good shots. No time wasted making unusable pictures :  When the sun is low if you have it in your back your prey doesn't see you in the blaze...

Unfortunately, my models tend to be highly mobile, seldom giving me the luxury of "framing" a shot.
My back yard: