Solargraphy is a technique in which a fixed pinhole camera is used to expose photographic paper for a length of time that is typically 6-months but can be as short as a few hours and last well over a year. Depending on the length of the exposure the resulting image shows the path of the Sun across the sky both from dawn until dusk, but also from North to South (or vice versa) between the solstices. Each light streak in a solargraphic image represents one day. Where light streaks are broken or missing indicates obstruction of the sun, which is caused by cloud cover.