Lentil is an advanced camera toolkit for the Arnold renderer. It is a set of shaders that extends creative control and physical correctness, while significantly reducing the time (~30x) needed to render bokeh through bidirectional sampling of camera rays.
Bidirectional By decoupling camera rays from primary rays, our bidirectional adaptive sampling of bokeh makes rendering depth of field in-camera practical.
Physical vs. Speed As often is the case in CG, there’s a choice between speed (thin-lens) and physical correctness (polynomial optics).
Creative control The thinlens model features additional creative control over the appearance of bokeh. See all features here. The polynomial optics model includes many different lenses to suit to your needs.
Files in /bin/$operating_system go to $C4D_INSTALL/plugins/C4DtoA/shaders
Files of type .str in /c4d/strings_us go to $C4D_INSTALL/plugins/C4DtoA/res/strings_en-US/description
Files of type .res and .h in /c4d/description go to $C4D_INSTALL/plugins/C4DtoA/res/description