Camera bloom (and other post-processing)

Cameras should probably be able to post-process images in order to create distinctive renders. For instance, it'd be great to have Polaroid, iPhone, pinhole, GoPro, etc cameras. The different lens types/ray scattering of these could already be implemented, but applying a 2d graphical filter on the resulting image would give more artistic range.

Start by tracing how cameras produce the resulting image and where a 2D graphical filter could be applied; the issue names no files or tests. Clarify the supported post-processing effects and acceptance criteria before implementation, since completion is not defined beyond adding artistic range to camera renders.

Written by the indexing model from the issue text.