Sunlight shines through some cool frost patterns on the inside of our window this morning. The temperature outside was well below freezing allowing for the moist air inside to condense as frost on the cold glass.
The patterns that form depend on the humidity and temperature of both the air and the glass as well as the properties of the glass since the ice will start as a "seed" crystal on an imperfection or scratch in the glass and then branches out from that crystal.
Also in black and white: http://www.lwpetersenphotography.com/Gallery/Black-and-White/i-htt9vFG
