I'm trying to get cinema 4d and processing to be friends. (So I can add high-end lighting to geometry I'm generating in processing.) After figuring out the basic issues of how they go about coordinate systems I'm getting results that are almost perfect. Which is odd. Usually things are either pear-shaped or perfect. So for the exact same numbers (geometry, camera position, camera target, field of view, aspect ratio, etc) I get 2 images that are essentially but not perfectly the same.

I've done a lot of compositing and usually the same numbers get you the exact same results. So cameras in after effects, maya, shake, cinema etc. behave exactly the same.

I'm thrown as to what's going on. It appears to be a slight (3-6%) difference in scale only and it's worse for bigger fields of view. Is it possible that processing handles 3d slightly different from other software?

Cheers, Jasper