Faking Diamond Caustics in After Effects

After consulting Mikey on the technical aspects of the diamond shader and trying to find a plausible way to apply caustics to the diamond shots in Maya - which physically through Maya will take considerable time when rendering, we figured that the best thing we can do is actually fake the impression of the caustics through the use of After Effects. Below is a series of screenshots to demonstrate the process I personally undertook to do so.

Through Maya, Mikey rendered 3 separate plates to composite on top of one another, the illuminate backplate, the diamond and the vault door animation sequence. These are then imported into After Effects in their sequences, and layered up to create the shot. We then have a composition that looks like this... 

I then layered up the shot utilising a mixture of Lens Flares from the Videocopilot Plug In for creating illuminating camera flares and also the use of After effects's default effect CC Light Rays, which is a handy tool that emits photons of light from any illuminated section of imagery within the composition. This can then be parented to only work with certain assets and therefore can be manipulated as desired. Mixing these two assets together, and layering them up on various adjustment layers, we begin to get a desired result: 

Until we have the desired look...and we've faked the illusion of Caustics and light rays emitting from a very shiny jewel. 

This was then implemented into the following two shots of the diamond.