Rings of Quételet are caused by rays of light which had been scattered by particles of dirt on a window pane and then were reflected from the rear side of the pane, interfering with rays having been reflected from the front side of the pane and then having been scattered by the same dirt particles.
The light source itself forms a white circle being surrounded by colourful rings which are caused by interferences.
These rings always begin with a blue one right outside the white circle and end up with a red one on the other side, away from the circle, no matter if the secuence begins in the centre of the pane or on its rim.
Place : Fehraltorf, Switzerland
Time : 24 August 2011
Digital Camera : Canon EOS 450D
Exposure time : 1/2500 sec , f/9 ,Focus length 22mm, ISO 100
Author: Michael Großmann, Kämpfelbach, Germany