Photographs: Negatives

PROCESSING AND PRESERVATION NOTE

The dates of production for the categories below are general use dates, not collection dates. All but the film negatives in good condition are restricted from handling by patrons. Most of the glass plate negatives have corresponding prints in the general photographs collection, although it is difficult to pinpoint exactly which ones without extensive research.

Wet Plate Collodion Glass Negatives (1851-ca. 1885)

These are the earliest negatives in the collection, and few in number. The process required on the spot coating of the glass, exposure and development by the photographer within about 15 minutes, requiring exceptional expertise. The wet and dry plate negatives are intermixed in the same subgroup and within series.

Gelatin Dry Plate Negatives (ca. 1878-ca. 1925)

The glass negatives collection is primarily made up of dry plate negatives, which could be purchased pre-coated and stored until needed. There is overlap between the use of gelatin dry plates and sheet film negatives between the 1900s and the 1920s here at Oberlin College.

Cellulose Nitrate Film Negatives (ca. 1889-ca. 1950)

In the early 1990s, Archives identified nitrate negatives in the collections and sought to reduce the hazards of storing them (off-gassing, decomposition, flammability). The staff embarked on a strategy for copying and printing nitrate negatives, after which they were destroyed. A list of high-priority negatives was made that justified the cost of interpositive generation. The Western Reserve Historical Society in Cleveland, which had a wet darkroom and a professional photographer, were already doing this work for their own negatives. Archives contracted with WRHS to make contact prints from their nitrate negatives, and to make contact interpositives, listed in this finding guide in Subgroup II, Series 3 and 4. The corresponding nitrate negatives were destroyed.

Lower priority nitrate negatives, primarily portraits of graduating classes, remain in the collection. These were scanned during the late 2000s and early 2010s by student assistants, although this project was not completed. Repositories today typically place their nitrate and other highly vulnerable negatives in cold storage rather than destroying them. However, cold storage space must be used for high priority materials, particularly moving picture film.

Cellulose Acetate Sheet Film Negatives (ca. 1925-2000s and possibly later)

While early acetate negatives are not flammable, they release harmful gases and acetic acid, and the film base contracts until the images are unreadable. As with nitrate negatives, cold temperatures will slow the process of deterioration. Archives staff identified a small number of seriously deteriorated Safety negatives, probably in the early 1990s, and saved them in a box in room 420A. These were “discovered” in 2017. Negatives from this box that retained some image integrity were scanned, printed, and then discarded in May 2018. The remaining acetate negatives will need to be tested for acidity and condition, and kept in cold storage. Nearly all of the remaining Princehorn sheet film negatives are acetate film base. Other collections besides RG 32/6 also contain acetate negatives, and possibly nitrate.

Polyester Sheet and Roll Film Negatives (1955-present)

Polyester film was developed for sheet and roll films in 1955 and is still in production, although less commonly used since the ascendance of digital photography.

In 1996, the Office of Communications transferred seventeen linear feet of photographic materials and related ephemera. The negatives in this accession, 1996/022, included glass plates, color slides, 35mm film negative strips, contact sheets and negative logs. The bulk of these were 35mm film negative strips dating from 1958 to 1970. These were sleeved and arranged in date order in the 1990s, but no index was prepared. In 2018 the negative sleeves were removed from hang folders and boxed.

In 2009, the Office of Communications moved to their present offices. Two accessions from that office in 2009 included a substantial amount of photographic material, including 35mm negative strips. These were sleeved and arranged into the categories set up for the print collection, in folders and boxes in 32/6. Additional smaller lots of negatives continue to be received from offices on campus and from private donors.

Of the negatives in this record group, the polyester film negatives are the most stable and can be handled by patrons with gloves, with care. Most of these have been sleeved and can be placed on the light table for viewing in the reading room.

Source Consulted

Maria Fernanda Valverde, Photographic Negatives, Nature and Evolution of Processes, 2^nd edition (PDF booklet), © 2005. Advanced Residency Program in Photograph Conservation sponsored by the Andrew W. Mellon Foundation, The George Eastman House, and the Image Permanence Institute. Accessed from https://www.imagepermanenceinstitute.org/webfm_send/302, 7/10/2018.

By Anne Cuyler Salsich, Associate Archivist, 7/10/2018.