I am taking thousands of photos on similar background and looking for things on top of that. The problem is that I see that the background color means and covs changes. That affects the colors of the things I am looking for.
What is the correct way to correct for that? Can I somehow normalize all the colors of the picture to the background?
My graphics editor (GraphicConverter for Macintosh) has a tool called White Correction. You click in an area of the image, and it shifts the color intensities so the area is pure white. Then it goes on and applies that color shift to the entire image. It's an easy way to remove tint from a photo.
There are user-defined color filter tools too but I have not created or used those.