As part of its heritage preservation project, the Musée de Bretagne is launching a project to preserve its photographic collections, which contain over 500,000 references. These archives are composed of negatives and prints on glass plates or flexible media (cellulose nitrate, cellulose acetate), slides and paper prints. The project began with dusting and reconditioning  the collections before sending them to digitization. We also took care of the delicate storage of cellulose nitrate supports’, which are flammable and present risks of degradation.