Modeling with light

Abstract The problem of making solid objects appear as they are—three-dimensional—is largely a matter of lighting. The subject occurs in the education of children, in the illumination of statuary, in photography, and in television; and the treatment has been almost entirely qualitative and empirical. This paper attempts to raise the problem to the quantitative level by introducing a numerical modeling ratio and by showing how the lighting can be predetermined by calculation to give any desired modeling, without recourse to the cut-and-try methods prevalent in the past.