The German photography artist Michael Wesely has created even longer exposures using a self-built pinhole camera. He captured the light of his objects for up to 3 years.

In 2001 he was invited by the Museum of Modern Art in New York to use his unique technique to record the re-development of their building. He set up four cameras in four different corners and photographed the destruction and re-building of the MoMa until 2004 - leaving the shutter (the holes) open for up to 34 months!

Beautiful!