35-mm rolls
The NDA team inventoried the 35-mm films in 2016. The collection forms a total of 1492 individual rolls, 30.5 m-long in average, which represents approximately 45km of film. Each roll included several observing sequences spread across different days, typically between 3 and 5 8h-long observing sequences each.
These films are divided as follows :
Decameter Array : 878 rolls
– 682 rolls obtained with the ’S’ or ’Spectrograph’ receiver between 1978 and 1980 ;
– 154 rolls obtained with the ’R’ or ’Routine’ receiver between 1979 and 1989 ;
– 40 rolls obtained with the ’RN’ or ’Routine-New’ receiver between 1990 and 1991 ;
– 2 rolls obtained with the ’SAO’ or ’Spectro Acousto-Optique’ receiver in 1983.
Decameter Interferometer : 601 rolls
– 436 rolls obtained with the ’S’ or ’Spectrograph’ receiver ;
– 149 rolls obtained with the ’MCX’ or ’Multi-Channel’ receiver ;
– 16 test rolls (duplicated rolls, tests of instrumental modes using the above mentioned receivers etc.).
Arecibo campaign : 13 rolls
– 13 rolls obtained with different receivers.
The films were stored in metallic boxes, some of which have been affected by rust. The RDN rolls were stored in three metal cabinets. The NDI and Arecibo rolls were stored in carton packaging or wood boxes.