IFLA Core Programme on Preservation and Conservation (PAC)Roosa, MarkRobb, Andrew2021-09-062004-07-052021-09-062004-0729127430361562-305 Xhttps://repository.ifla.org/handle/20.500.14598/1311Photographic materials have complex physical and chemical structures that present special preservation challenges to the librarian and archivist. Since the birth of photography in the late 1830s, many different photographic processes and materials have been utilized, each subject to deterioration through time and with use. Although deterioration is an ongoing natural process, nevertheless much can be done to slow the rate at which it takes place in photographs. Deteriorated photographs may require specialized conservation treatment by a professional photograph conservator, often a costly, skill-demanding, and time-consuming procedure. For the majority of photographs in research collections, single-item conservation of deteriorated photographs is probably not a feasible or a cost-effective preservation solution. Instead, preventive conservation actions such as maintenance of a good environment, promoting proper care and handling through staff and user education, and the use of good quality storage housings, will have a more lasting, positive impact on the preservation of a collection. This publication is intended to provide a basic understanding of how and why photographs deteriorate and what can be done to slow this process. The information below focuses on the photographic formats most commonly found in research libraries and archives, namely black-and-white silver prints, glass plate and film base negatives, color chromogenic dye photographs (including negatives, prints, and transparencies), and digital output or hard-copy: ink jet prints, dye sublimation prints, and electrostatic prints.enSubject::PreservationSubject::Preservation and conservationSubject::Care, handling and storage of library materialsSubject::Photographic materialsSubject::Cultural heritageStandardsInternational Federation of Library Associations and Institutions (IFLA)