21 Nov 2000 Experiments with Polarised Light
A piece of cellophane paper
Audio cassette case
CD jewel case
Linex drawing curves
Crumpled cellophane paper
Thin mica washers, as used for insulating power transistors
The technique for taking these photographs is first to re-mortgage your house and buy a sheet of polarising film, which is illuminated from behind via a diffusion sheet. The camera lens has a polarising filter fitted which is rotated until it is at right angles to the sheet, so the viewfinder looks dark (the digital camera does not have a filter thread on the lens, so to take these I just held the filter in front of it). The object to be photographed is placed between the polarisers. All you have to do then is find some things to photograph - plastic works well, as does cellophane paper of the type usually used for wrapping foodstuffs. Thin sheets of mica, if you can find some, can produce some spectacular effects. The correct exposure seemed to be about one stop less than indicated by the camera's metering.