A new method for determining the modulation transfer function (MTF) for photographic films is described. The MTF and corresponding line spread function are approximated by carefully chosen models which are uniquely specified by a few parametric constants. By estimating the parameters in space and frequency simultaneously, the interactions between the two domains result in improved estimates over those provided by either domain alone. A computer algorithm has been written to determine the parameter constants that define the best-fit model for the emulsion MTF
