Test objects that vary sinusoidally in transmittance have been made by photographing variable-width sinusoidal test objects with cylindrical optics and printing the negative in such a way that the over-all gamma of the negative-positive combination is approximately unity. A gray scale is included with the test-object array and serves to calibrate the various levels carried through the systems that are tested. Methods of use are described and a practical example is given.
Robert L. Lamberts, "The Production and Use of Variable-Transmittance Sinusoidal Test Objects," Appl. Opt. 2, 273-276 (1963)