Skiopticon image from the Department of Photography at the Royal Institute of Technology. Use by Professor Helmer Bäckström as lecture material. Bäckström was Sweden's first professor in photography at the Royal Institute of Technology in Stockholm of extinction curves for yellow and blueyy more info See: Sjöstedt 1941?

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Size: 2708px × 1846px
Photo credit: © BTEU/TEKNISKA / Alamy / Afripics
License: Licensed
Model Released: No

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