Iridescent Clouds Above Quezon City, Philippines
July 08, 2010
Photographer: Erika Valdueza; Erica's Website
Summary Author: Erika Valdueza; Jim Foster
The photo above showing brilliant iridescence was taken from the Manila Observatory, Quezon City, Philippines. Iridescence or irisation is generally rather subtle but at times can be striking. It's caused by diffraction of sunlight; the same phenomena that produce coronas and spider web iridescence. Iridescence is typically confined to mid-level clouds, between 5,000 ft and 15,000 ft (1,524 - 4,572 m) that are comprised of minute water droplets. These droplets act to deflect sunlight, which results in overlapping colors and, hence, pastel shades. Colors are purer and brighter when the droplets are close in size throughout the cloud. Also of note are the building cumulonimbus clouds at left. Photo taken on June 23, 2010.
Photo details: Camera Maker: Canon; Camera Model: Canon EOS DIGITAL REBEL XSi; Focal Length: 39.0mm; Aperture: f/8.0; Exposure Time: 0.0003 s (1/4000); ISO equiv: 200; Exposure Bias: none; Metering Mode: Matrix; Exposure: Manual; Exposure Mode: Manual; White Balance: Auto; Flash Fired: No; Color Space: sRGB