Here is my take on the request presented here :
reshade.me/forum/shader-suggestions/5890...niformity-correction
I wrote a simple shader for this problem, I tested it with a bad camera on my monitor with backlighting problems.
Here is my monitor without the shader (contrast is increased to show the imperfections) :
And here is with the shader applied (same contrast as before) :
Effect could be better with a good camera.
Shader and how to here :
github.com/AlucardDH/dh-reshade-shaders
Maybe, the effect will be different with a projector, feedback is welcomed.