ABSTRACT A recent revisionist theory claims that as early as 1430 European artists secretly invented optical projectors and used them as aids during the execution of their paintings. Key artworks adduced in support of this theory are a pair of portraits of Cardinal NiccolÒ Albergati by Jan van Eyck: a silverpoint study (1431) and a formal oil work (1432). We tested whether the use of known contemporaneous mechanical methods might explain this image evidence as well as the use of optical methods, also explaining additional physical evidence. We used traditional image processing techniques, as well as “re-enacted copies” by professional artists using mechanical methods. We found that the fidelities of these modern “re-enactments” were equal or superior to those of the van Eyck works.

David Hockney has recently hypothesized that some early Renaissance painters employed optical devices such as concave mirrors to project images of a scene or part of a scene onto their supports, which they then traced or painted over. As one of many examples, he has claimed that Hans Memling (ca. 1440–1494) built an optical projector to create his Flower Still Life, specifically when rendering its carpet. The author's perspective analysis on the image of this carpet shows that, while there is a “break” in perspective consistent with refocusing or tipping of an optical projector, there are also other larger, more significant perspective deviations that are inconsistent with the use of a projector. After presenting a simple sensitivity analysis of these results and rebutting anticipated objections, the author concludes by rejecting the claim that optical projections were used in the creation of this still life.