Those of you who had a chance to play with Fryrender, Maxwell or Indigo probably used or at least heard about their ability to simulate lens aberration. Although these implementations may differ slightly they’re all based on the same algorithm made by a bunch of guys working hard at University of Tokyo back in 2004 (more info).
This algorithm can simulate a glare effect that is caused by tiny imperfections on a lens. Besides this, it can imitate a situation when the lens (or iris) is partially occluded. For example by cross filter or eyelashes.
Basically, you bring two maps, one for obstacles and one for aperture, set the multiplier, the amount of diffraction, and the algorithm will do the rest. The whole generation process is physically based.
It’s quite fast too, but the best thing about it is that you are able to fully customize the power and the shape of diffraction patterns by experimenting with your own aperture and obstacles maps, on the fly.
Fryrender comes with few nice maps, but I did some additional stuff to make this feature more flexible. You can download them here. They should be compatible with Maxwell SimuLens™ and Indigo Render as well.
I also did a small preview scene to show you guys some interesting combinations of aperture and obstacle maps.
Rendering time: 5 hours 30 minutes
Click for full resolution.
You're free to use, change, experiment with these maps. I hope you'll find them useful.