A uniform secondary exposure of low intensity is made to a normal or underexposed primary latent image for approximately 5-15 minutes, to increase the effective speed index. This is first studied from a white light approach similar to that used in single emulsion negative materials.
In addition, the ability to manipulate and align individual layers by selective filtering was also studied. Red, green and blue filters, matched closely to the spectral sensitivity of each layer, were used separately and conjunctively towards achievement of the desired levels of effective speed, contrast, color balance and maximum density.
Latensification by a secondary white light exposure increases the effective A.S.A. speed of specific layers by as much as 2 1/2 f/stops.
Through selective filtering, an ability to increase speed and align two or more layers has been demonstrated.
The effective overall speed of Ektachrome-X film has been increased by a factor of ~ (2) but at the expense of losses in Dmax.; contrast; and color balance.
Library of Congress Subject Headings
Photographic sensitometry; Photography--Films
Tietjen, Thomas A., "Post exposure latensification of a multilayer color film" (1967). Thesis. Rochester Institute of Technology. Accessed from
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