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In the evaluation of conventional photographic imaging systems the non-linearity of the macroscopic curve can easily be dealt with by examining the "effective exposure" rather than expressing the density or transmittance. Dealing with the nonlinearities on a microscopic level, however, is very difficult since they result from development adjacency effects. A tool was made using a "V-shaped" groove design by G.W. Schumann which consists of a series of microscopic linear density wedges. The density wedges were made by filling V-cut grooves in a high quality acrylic plastic with a carbon-epoxy dispersion. The density wedges have been produced at the frequencies of 0.98. cy/mm and 0.57 cy/mm. These wedges have effective diffuse density ranges between 0.21 and 1.18. Their density gradient has been varied from .28 to 2.58 density units per mm. The wedges were then tested for their practicality for use in image evaluation. It was found that the characteristic curve for a small image area with a low surrounding density is higher in contrast and shifted to a higher speed when compared to a conventionally produced curve. When the micro scale density wedges were imaged with a high surrounding density, the results were not significantly different from those obtained with the conventional step wedge. There are several drawbacks attributed to the V-groove design that are discussed. The results from the practical application tests, however, suggest that there is significant merit for the micro scale wedges for use in the study of chemical adjacency effects. The micro-scale continuous density wedges are found to present a new concept to sensitometry where the characteristic curve can be related to some of the adjacency effects encountered in specific applications.

Knowledge of how an image is changed by a given modification of its Fourier transform is important when attempting to find solutions to problems in image processing. Several types of filters were used to modify the Fourier transforms of an edge and a bartarget. The images were reconstructed from the modified transforms to determine the change produced by a given modification. Various regions of the Fourier transform determine specific characteristics of the image. The amplitude of the low frequencies controls the form and average level of the image, while the amplitude of the high frequencies effects sharp transitions and noise.

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.

The problem of this experiment is to determine which of three factors; sulfite level, bromine level, and development time, affect the image spreading during the infectious development of a graphic arts film. Three different levels of each factor will be studied. The method used consists of measuring the distance between two fine edges on a test target. This test target is then contact printed onto the graphic arts film. The distance between the two fine edges on the graphic arts film is then measured. Any difference between the two distances will be the result of image spreading. It is these distance differences that are used as the response in the three level, three factor Yates analysis. The sulfite level has been found to be a significant factor. The conclusion is that the sulfite concentration affects the image spreading during the infectious development of graphic arts film, but not bromine level or development time. The film tested was Kodak Kodalith Ortho, Type 3.

Interimage effects have long been recognized as a factor in the reproduction of color. Reversal materials are no exception and exhibit interimage effects which have previously been revealed through techniques using END analysis. This study presents a method for revealing the presence of interimage effects in a reversal film's Modulation Transfer Function. Utilizing filtering techniques, two dyes of a three color transparency are eliminated from the final image by exposure and development. The remaining single dye image at a specified level is then compared to the corresponding layer and image in a colorimetrically specified neutral. The edge gradient analysis method is used to calculate the Modulation Transfer Functions. MTF results indicate the desirability of using colorimetry for the specification of a visual neutral. MTF values are indicative of a significant effect on the Modulation Transfer Function by interimage effects.

A new procedure for obtaining the Chemical Spread Function of an emulsion-developer combination is discussed. This procedure consists of directly measuring the Optical Modulation Transfer Function (MTFO) by scanning the sinusoidal object irradiance distribution through the non-developed emulsion using a microdensitometer. The Modulation Transfer Function (MTF) of the processed emulsion is determined in the conventional manner. Then the Chemical Modulation Transfer Function (MTFC) is determined from the linear relationship: MTF = MTFC X MTFO. Once the MTFO is determined then the Spread Function is calculated using the Fourier Transform operator. Photographic systems are in general non-linear. However it is well known that for moderate input modulation and relatively small gamma the photographic material acts linearly. Results are obtained for Kodak High Contrast Copy film 5069 processed in Kodak D-76 developer. It is concluded that this method can be used to determine the Chemical Spread Function of more widely used film-developer combinations. Recommendations are made for improvement to the method to obtain more accurate results.

An investigation is developed for determining whether certain factors, which are characteristics of a photographic edge, are of significance in the derivation of the modulation transfer function of a system from the edge. Factors investigated were edge spread, density range (contrast), and background density. The experiment was limited as to levels used but it was determined that the edge spread significant and a minimum allowable edge spread was calculated.