Time-lapse of prism spectra at the National Museum of the American Indian, September 2015
On sunny days, prisms set high in a south window of the National Museum of the American Indian in Washington, D.C., spill bright spectra on the floor and walls of the Potomac Atrium. The path of these rainbow colors changes throughout the year, and the spectra line up in special ways on the equinox and solstice. This particular time-lapse, shot in HDR, was filmed on September 18, 2015, just a few days before the fall equinox and the anniversary of the opening of the museum on the National Mall. Charles Ross prism installation, National Museum of the American Indian, Washington, D.C.