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.