Science Fair Project Encyclopedia
The camera obscura (Lat. dark chamber) was a novelty optical invention, and one of the ancestral threads leading to the invention of photography; photographic devices today are still known as "cameras".
Simply do it yourself by building a box and punching a hole in one of the walls - voilą! (see Pinhole cameras for construction details) With a small enough aperture, light from only one part of a scene can strike any particular part of the back wall; the smaller the hole, the sharper the image on the back side. With this simple do-it-yourself apparatus, the image is always upside-down, although by using mirrors it is also possible to project a right-side-up image. Some camera obscuras have been built as tourist attractions, though few now survive. Examples can be found in Grahamstown in South Africa, Bristol in England, Aberystwyth and Portmeirion in Wales, Kirriemuir, Dumfries and Edinburgh in Scotland, and Santa Monica and San Francisco, California.
The principle of the camera obscura has been known since antiquity. Their potential as a drawing aid may have been familiar to artists by as early as the 15th century. Leonardo da Vinci described the camera obscura and it has been widely speculated that Johannes Vermeer made use of one, but the extent of their use by artists at this period remains a matter of considerable controversy.
Early models were large; comprising either a whole darkened room or a tent (as employed by Johannes Kepler). By the 18th century, following developments by Robert Boyle and Robert Hooke, more easily portable models became available. These were extensively used by amateur artists while on their travels, but they were also employed by professionals, including Paul Sandby, Canaletto and Joshua Reynolds, whose camera (disguised as a book) is now in the Science Museum (London). Such cameras were later adapted by Louis Daguerre and William Fox Talbot for creating the first photographs.
A small, hand-held version using photographic paper to record the image is known as the pinhole camera.
- An Appreciation of the Camera Obscura
- Flash Animation - Flash Animation that explains how the Camera Obscura works
- The Camera Obscura in San Francisco - The Giant Camera of San Francisco at Ocean Beach, added to the National Registry of Historic Places in 2001
- Vermeer and the Camera Obscura by Philip Steadman
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