Experiments with E. H. Land's Two-Color Projection

Since the quality of E. H. Land's two-color pictures has been subject to discussion, two groups of students were asked to judge the quality of Land's pictures. The preparation of the slides and the experimental setup is described. The results show the inferiority of E. H. Land's system in its actual form to ordinary tricolor projection. From the results it appears that the mechanism of color transformation works well with most people tested, but that the lack of information contained in the slide photographed through the blue filter is considered serious. An interesting detail is that a minority of people can detect very little or no difference between the two forms of projection.