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Pushing E200: Exposure

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To compare the exposure behavior of push processing, two similar frames were scanned. These are wide angle views of the Milky Way taken with a 20mm lens at f/5.6 for twenty minutes. The two films were positioned next to each other on the drum and a single scan was made. The resulting digital image was level-adjusted slightly to allow a visual comparison between the two sections. The result is that neither image is properly presented, each would be improved by individual scans. It does however show the relative levels between the two exposures. The top section is the push-processed film, Taken in March, Orion is obvious at the lower left, and the Milky Way runs horizontally across the frame. The green glow of rural security lights creep into the bottom of the frame. The overdeveloping is evident in comparing the film base. The full black is lost compared to the normally developed frame (but would be restored by proper scanning). The bottom half is processed normally. It was taken in July; the summer Milky Way runs vertically through the frame. The bright stars Altair and Vega are at the center and upper right. The stars are more colorful, a result of their not saturating the emulsion. Far fewer of them are recorded however, and the limited density range of the Milky Way does not fully reveal its subtle variations.   See also a grain comparison of pushing E200.

Copyright 1999-Jul-19

Thor Olson