Agfapan Vario-XL film was faded at various levels of temperature, humidity, light, and fade time to determine the mathematical relationships of these variables and to examine whether interaction occurs between each factor. Light stability of the film was measured, and the Arrhenius relationship was used to predict dark stability at ambient storage conditions. It was found that the amount of fade, as measured as either a change in transmittance or density, could be mathematically modeled with a high degree of correlation. Each independent variable (temperature, humidity, and time) was interactive with the other two variables. Under the specific conditions tested, as a significant interaction existed between light and dark fading reactions. For example, both the light and dark cyan dye reactions inhibit each other. However, in the case of the magenta and yellow dyes, a synergistic, or catalytic, effect occurs when light fading precedes dark fading. Agfapan Vario-XL is extremely light stable when irradiated by a conventional enlarger light source. An intermittency effect was noted. The dark stability compares with some of the least stable chromoegenic print films - - a ten percent loss in printing density is predicted by Arrhenius extrapolation when the Agfapan Vario-XL is stored at room temperature at 45 percent relative humidity for five years,

Library of Congress Subject Headings

Images, Photographic

Publication Date


Document Type


Department, Program, or Center

School of Photographic Arts and Sciences (CIAS)


Pearson, Milton - Chair

Advisor/Committee Member

Reillv, James

Advisor/Committee Member

Francis, Ronald


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: TR222.D37 1982


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