First of the Arizona pics to upload from my 2012 trip. This one was taken from a tour boat on Saguaro Lake up in the mountains just north of Phoenix. The entire lake is a deep resivour nestled in a flooded mountain valley of the Salt River.

A speedboat streaks up the channel, having a fast enough shutter speed to freeze both the boat and the rooster-tail of its wake. If you look very closely you can see some faint rainbow-distortion in the wake, caused by the sunlight hitting it.