A
pinhole camera, a variation of
Camera obscura, is a simple
camera without a
lens and with a single small
aperture, a
pinhole – effectively a light-proof box with a small hole in one side. Light from a scene passes through this single point and projects an inverted image on the opposite side of the box. Exposures can typically range from five seconds up to as much as several hours. The effect was noted in the 5th century BC in China and has been refined over the centuries.