Alexander’s Dark Band and Double Rainbow

May 30, 2011

Photographer: Lisa Gonnelli
Summary Author: Lisa Gonnelli; Jim Foster

The photo above shows a classic double rainbow separated by Alexander’s dark band. Actually this darkened strip of sky between the primary and secondary bows is due to the reflection (and refraction) of sunlight in raindrops -- the dark band is deprived of this light. Essentially only scattered sunlight reaches this region. In regards to the bows themselves, brilliant colors are more likely to result when the raindrops are bigger. Note also the supernumerary bows on the inside of the primary bow.

Photo details: Camera Maker: OLYMPUS IMAGING CORP.; Camera Model: E-500; Focal Length: 35.0mm; Aperture: f/4.8; Exposure Time: 0.017 s (1/60); ISO equiv: 125; Exposure Bias: none; Metering Mode: Matrix; Exposure: Creative Program (based towards depth of field); White Balance: Auto; Flash Fired: Yes (Auto, return light detected); Orientation: Normal; Color Space: sRGB.