James Greene


This report documents a study conducted to examine the correlation between identification thresholds and difference spectra of some resolving power target characters. The experiment included the USAF Tri-bar target, the RIT Alpha-numeric Resolving Power Target, and a set of targets called the Granger Modified Tri-bar targets. Assuming that target identification is a filtering process and primarily a function of its frequency spectrum, this study began with a prediction of targets that would have equal identification thresholds from difference spectra considerations. Target images were viewed at various sizes to confirm/refute the original hypothesis. The USAF targets demonstrated adequate control of experimental variables. The RIT and Granger characters both revealed the existence of one or more factors in addition to difference spectra which significantly contribute to target identification. It is conjectured that boundary effects may be that important contributor to image identification.

Library of Congress Subject Headings

Resolution (Optics); Photographic optics; Fourier analysis

Publication Date


Document Type


Department, Program, or Center

School of Photographic Arts and Sciences (CIAS)


Francis, Ronald

Advisor/Committee Member

Granger, Edward

Advisor/Committee Member

Schott, John


Note: imported from RIT’s Digital Media Library running on DSpace to RIT Scholar Works. Physical copy available through RIT's The Wallace Library at: TR220.G69 1983


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