Controversial methods
For more than a hundred years, it has been suggested that the great 17th-century Dutch master Johannes Vermeer made use of the camera obscura as an aid to painting. The camera obscura was the predecessor of the photographic camera, but without the light-sensitive film or plate. It is well established that in the 18th century some other famous painters employed the device, the best-known being Canaletto, whose own camera obscura survives in the Correr Museum in Venice. The English portrait painter Sir Joshua Reynolds owned a camera; and the device was widely used by landscape artists, both professional and amateur, up until the invention of chemical photography in the 1830s. With Vermeer the question of whether he used optical methods is more controversial.
'The camera obscura was the predecessor of the photographic camera, but without the light-sensitive film or plate.'
The term 'camera obscura' means 'dark chamber', because the instrument up until the 16th century typically took the form of a closed room, the windows shuttered, with a small hole in a blind or door. Light entering the room through the hole then cast an image onto a screen or onto the wall opposite the door. One problem is that the image in such a 'pinhole' camera, even of a sunlit summer landscape, is very dim. The one object that is clearly visible is the sun itself. Indeed this remained the only real application of the camera up until the 1550s: for astronomers to make solar observations without damaging their eyes. The first published illustration of a camera (of this or any type), is in a book from 1545, by the Dutch mathematician and astronomer Gemma Frisius. It shows an eclipse observed by Gemma Frisius at Louvain in the previous year.
The situation changed in the mid-16th century, when it occurred to a number of people, it seems simultaneously, to substitute glass lenses for simple pinholes. Typically these were convex lenses of the kind then in wide use for the correction of long sight. Two Venetian authors, for example, give clear descriptions of cameras with convex lenses - Daniele Barbaro in 1568 in a perspective manual for architects and painters, and GB Benedetti in a mathematical text of 1585. These authors describe how to draw from the camera image by tracing outlines onto the paper screen. Others even hint at the possibility of laying down colours over the projected image, although this idea is problematic. (How could you see the colours of your paints in the darkness of the closed room?)
Published: 2002-09-23
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