Digitization of films
The digitization of 35-mm films first required to define requirements to correctly sample the time and frequency resolution together with the intensity dynamics. Afterwards, the OSIC specialized company, based in Marseille (France), has been selected to execute the data digitization.
Transport and processing
Once delivered to OSIC, the rolls have been individually prepared (cleaning, electrostatic discharging etc.), digitized and repacked in adapted storage devices (plastic roll cores, carton storage boxes) before to be restituted to the Observatory of Paris. The full digitization of the 1500 films was executed between Sept. 2018 and August 2019.
Digitization
The employed digitization scanner, a Wicks & Wilson 8850 type, was capable of scanning 35-mm films at high resolution.
The films have been digitized at the uncompressed TIFF format as a series of successive images, with 15744 x 5408 pixels resolution, with a 1 pixel error between two consecutive images. The nominal intensity dynamics of 8 bits (256 values) has been triggered manually and separately for each film, and kept constant for all the digitized images of a given film.