On the first dark night move this ‘cropped bokeh’ effect was this was requested by Chris Nolan because the dop Wally Pfister had generated it from his collection of ‘character lenses’ and we needed to match the plate. A very clever chap Adam Paschke now a Rising Sun supervisor, was asked to emulate this Vignette flag effect in Shake.
It is the effect of the cropping of the bokeh in the image, outside the field of view but inside the bokeh’s field of fiew. It is most often seen in films when the top ‘french flag’ of the camera is really close to the field of view too stop flare from a light souse. This then has the often unintentional effect of cropping the edge of the bokeh.
On the second Dark knight film they wanted the same effect but it had to be re-written because of different composting software. I helped developed the port and then I introduced these additional features:
Barrel Vignetting aka ‘cats-eye effect’
Chromatically arbitrated Bokeh
I have had the fortune to work as a compositor and CTD on sequences that have used this tool that i helped make, including these beauties.
To learn more about bokeh go here http://toothwalker.org/optics/bokeh.html
This node is in beta and has not been thoroughly tested in an production environment. Use at your own risk.
To improve this tool go join gitub and contribute here (once it is stable we can release it on nukepedia)