For a portrait shoot, I created a custom 2001: A Space Odyssey inspired diffusion rig. It is essentially a box that contains slides - each slide has nylon pantyhose material stretched across it. Part of the lens always sees through this diffusion material, so it scatters light without making the picture unsharp. Here is the process behind building the rig, reverse engineered from an article about the effect, which can be found here;
http://www.2001italia.it/2013/05/making-starchild-in-2001-tribute-to-liz.html
