Iridescent Clouds Over Athens, Greece

November 28, 2010

Photographer: Chris Kotsiopoulos
Summary Author: Chris Kotsiopoulos; Jim Foster

The photo above shows colorful cloud iridescence as observed over the Chalandri suburb of Athens, Greece. Iridescence occurs in clouds that are composed of minute water droplets. Due to their diminutive size, they deflect rather than refract sunlight. Iridescent clouds are, in essence, pieces of detached coronae. Care must be taken when looking for them because they are generally found close to the Sun. The most conspicuous colors occur when the cloud droplets are nearly the same size throughout the cloud. Photo taken on October 16, 2010 at 5:44 p.m.

Photo details: Canon EOS 550D camera; Canon EF70-200 mm lens; Focal length 200.0 mm; Shutter speed 1/4000; Aperture 13.0; ISO 100.