Abstract

The use of instruments for drawing from life is documented since the fifteenth century in a variety of books, drawings and actual devices. Almost all of the instruments invented for this purpose belong to the linear perspective tradition, being conceived as mechanical expressions of a geometric principle, namely the intersection of the visual pyramid. On the basis of a close but controversial analysis of some important paintings of the early Renaissance, David Hockney and Charles Falco have concluded to a widespread use of optical devices in painters' workshops, such as concave mirrors, convex lenses and camera obscuras. Devices of this kind were generally used by optics scholars in their experiments with light and the multiplication of species. However, except for some isolated references to the camera obscura and flat mirrors,1 the documentary history of art is completely silent about the use of these optical tools by painters. Written evidence, in this sense, can be found only in the late sixteenth century but related to map-making more than to painting. Moreover, growing interest in such devices is only evident in connection with the invention of the telescope and its interpretation as an "artificial eye."2