Holographic pictures inducing additional standard object - designed to reveal angle between directions of illumination and observation

摘要

The subject of the picture is to include also an object containin a co-ordinate system. This consists of three squares (2, 3, 4) joined to form a trihedral angle, with a set of concentric circles drawn centrally on each square and a small sphere (5) at the centre of the cube of which the squares form three faces. This object is set up in the pictorial composition so that the illumination to be used casts a shadow of the sphere (5) centrally on one face of the cube (11). In the finished picture the sphere will, in eneral, appear elsewhere. The distance (7) from its apparent position to the centre of the square is shown by concentric circles, serving as co-ordinate curves.