Dew bows are a kind of rainbows. The difference lies in the plane of projection and in the fact that static droplets are reflecting the refracted light back into the eyes of the observer. The rainbow cone resulting, the apex of which is the oberver´s eye, is cut by the plane (the field). The result is a hyperbola, but for our eyes, there is always a circle!.
The first nights in October were rather cold, so that a lot of dew could form in the fields.
I knew that the following days were ideal for looking for the dew bow.
The main problem while observing dew bows is the brightness of the field. A polarization filter makes the dew bow contrast better from the background. (2)
An even better idea was filming the dew bow while driving along the farm track. This makes it contrast even more clearly.
Place : Neulingen, Germany
Time : 02 October 2011
DSLR Camera : Canon EOS 450d
Exposure : 1/25 sec, f/10mm, F/7, ISO 100
Author: Michael Großmann, Kämpfelbach, Germany