Rainbow Fragment Over Paris, France

April 22, 2019


Photographer: Bertrand Kulik
Summary Authors: Bertrand Kulik; Jim Foster

While bright rainbows always get our attention, sometimes the most alluring bows aren't the big arching ones with vibrant colors. The fragment of a primary rainbow shown here juxtaposed with the Eiffel Tower draws the eye to its subtle charm. Larger drop sizes result in purer colors. However, since not every single light ray entering a raindrop, after being reflected and refracted, emerges at the minimum angle of deviation (also called the rainbow angle and which varies from about 139.5 degrees for blue light to about 137.5 for red light) the colors of a rainbow are somewhat smeared, regardless of the drop size. Of course, other factors affect how brilliant a given rainbow may appear, including the presence of haze or smog in the viewer's line of sight. Photo taken on March 4, 2019.

Photo Details: Canon EOS 7 D camera; EF100mm f/2.8L Macro IS USM; EF 50 mm; f/5.6.8 STM; ƒ/13.0; 100.0 mm; 1/5000 second exposure; ISO 400.