Abstract
The digital reproduction of a historical motion picture should resemble as much as possible the analog film projection at the time of the movie release. Nowadays, practices of capturing digital images of films do not properly consider the fundamental elements and conditions of the original film projection. The typical rigid three-band (RGB) capture cannot adapt to the multitude of historical color film stocks to be digitized, and the diffuse illumination on the film generally used by standard digital scanning devices is unable to guarantee the proper visual rendition of the original analog projection of film prints. In order to overcome these problems, we designed and built a novel multispectral imaging system that illuminates the film with a condensed light beam. The new imaging system and the computational pipeline were tested on an assorted set of photographic colors. The accuracy of the multispectral captures was tested by comparison with corresponding spectrally resolved point-based radiometric measurements of the light reflected by a screen during analog projection. The presented optical design represents an excellent solution for the creation of a new multispectral motion picture scanner prototype. The LED-based illumination system coupled with a film transport mechanism can be the core concept of a promising new generation of motion picture film scanners.
Trumpy, Giorgio