How to use a camera lucida
The camera lucida is generally considered to have been invented by the English chemist W. H. Wollaston in 1806-07, although there is some speculation that it is a reinvention of a device described by Kepler some 200 years earlier. The term camera lucida means 'light room' and it indicates that the device didn't require the darkened space that had been necessary for the earlier camera obscura. There is no projected image and it is based on very different optical principles. A camera lucida consists of a simple prism and lens that allow an artist to see the scene that they depicting superimposed over the paper that they are drawing on, so that they can simply trace around the image. The rest of the device comprises of a clamp and extendable arm, with which it can be securely fixed in position to one side of the artist's drawing board or sketch pad with the prism set at a convenient height. A French camera lucida or 'Chambre Claire Universelle', made by Breveté S.G...