A camera lucida (or sometimes camera lucida ) is an optical device used like helps with the Dessin by the artists and patented in 1806 by William H. Wollaston.

The camera lucida carries out an optical superposition of the subject to be drawn and surface where must be deferred the drawing. The artist uses this superposition to place key points of the subject to be reproduced, or even his broad outlines. The prospect is reproduced in a perfect way, without construction.

In the case of the use of blank paper for the drawing, work is made difficult because its luminosity obstructs the draftsman. It is preferable in this case to work with black paper, or of sunk color, and a white pencil.

The camera lucida of Wollaston, as the diagram of left shows it, uses a prism. The apparatus is laid out so that half of the pupil of the eye E looks in prism ABCD, perceiving the subject to be drawn, mixing the direct vision of the surface of drawing. The lenses L and equalize It the optical distances from the subject S and surface P of drawing.

In 2001, the painter David Hockney generated a violent controversy with its work Secret Savoirs; Lost techniques Of the Former Masters in whom it shows that an important part of the great painters of the past, like Ingres, Van Eyck and Caravage, did not make by their drawing with freehand but by using optical devices like the camera lucida , darkroom or of projections of images by concave mirrors. Work of Hockney was criticized by Ross Woodrow, of the University of Newcastle in Australia.

However, one should not lose sight of the fact that, like says it Hockney, it is always the hand of the artist who draws.

See too

• Darkroom
• the Camera lucida (1980), work of Roland Barthes on photography.

Zh-yue: 投影描繪器