# Removing vignetting created by film camera lens **URL:** \ **Category:** Image Editing Help\ **Created:** [September 5, 2024, 10:52am UTC](https://forums.negativelabpro.com/t/removing-vignetting-created-by-film-camera-lens/8150 "2024-09-05T10:52:55Z")\ **Posts on this page:** 1\ **Showing post:** 10
**Author:** ![ArnoG](https://avatars.discourse-cdn.com/v4/letter/a/ac8455/32.png) [@ArnoG](https://forums.negativelabpro.com/u/ArnoG)\ **Post date:** [September 16, 2024, 2:11pm UTC](https://forums.negativelabpro.com/t/removing-vignetting-created-by-film-camera-lens/8150/10 "2024-09-16T14:11:40Z")
Hi all, Read this: > [@Integrating sphere as a uniform backlight](https://forums.negativelabpro.com/t/integrating-sphere-as-a-uniform-backlight/6302/58): > > Hi all, As mentioned in the first post in this forum thread, a finite planar light source (such as an LED panel) will always result in an inhomogeneous light distribution on film. A planar light panel a give a homogeneous light distribution on film, provided it is infinitely large compared to the film, which is not practical for table-top solutions. It took me a while to get this done, but I just calculated the brightness inhomogeneity on a film that results from using a planar light source tha… and this: > [@Integrating sphere as a uniform backlight](https://forums.negativelabpro.com/t/integrating-sphere-as-a-uniform-backlight/6302/66): > > Small update: I managed to quite accurately create a brightness mask in LRC. The procedure is as follows: Take a shot of a blank B&W negative Import with Linear B&W profile (e.g., NegativeLab v2.3 B&W) Analyze the variation of brightness (if any) in LRC in the development module by hovering over the frame and looking at the R, G, and B values: They should be the same (since B&W) and constant across the frame Crop to see only the blank negative Apply a radial mask: My light panel is square, so… --- _[View the full topic](https://forums.negativelabpro.com/t/removing-vignetting-created-by-film-camera-lens/8150)._