I am currently restoring some old 8 mm film reels. My cmos camera displays a greenish tint in the centre of the image at low exposure settings. I am looking at the possibility of applying a complimentary colour mask over the image to neutralize this effect but am not sure how to achieve this - suggestions would be welcome.........
I did something similar, but with some old Kodachrome slided that had a magenta cast in the center. What I did was make a somewhat roundish mask that matched the area using the elipical marquee tool, with the feathering set to give an even blend, then filled with a compimentary shade of green, took some experimenting to get it right, then adjusted the opacity of the layer to taste. Was by no means perfect and I had to use the clone too to clean up some areas, but got some decent 8x10 prints in the end and the customer was happy, and that's what counts Oh!, and this was quite labor intensive, but only had 5 images to fix up. Sounds like you have a bunch to do, but once you have got it right you can always copy your correction layer to the other open images.
Good luck and maybe someone has ideas on a better solution for you
Try a different lens first. It's a long shot, but easy to test.
I'm doing some IR photography at work, and the 55mm Micro Nikkor consistently gives a bright circle in the center of the frame, while the regular 50mm 1.8 does not. I just couldn't figure it out until I noticed the circle varied with aperture. My point is that this could be some "freak" IR leakage.
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