It should be noted that polyester is also widely used today as a support for negative materials. Approximately 85% of albumen prints, however, show some stain formation in the white and highlight areas. The proper, safe, and economical storage of glass plate negatives is a problem which continues to plague photographic archives. This froth covering the emulsion side of the film appears iridescent and obscures the photographic image. Image by Wikimedia Commons user Mjmphotos, available under a Creative Commons Attribution ShareAlike license. Since buffered paper has been shown over time to drop in pH, this is only an issue for the first 10 years or so of the package's lifetime, after which the enclosure is neutral pH or slightly acidic.
Glass plate negatives are generally stored in sturdy P. Suppliers for Photographic Storage Enclosures Conservation Resources International 111 North Royal Street Alexandria, Virginia 22314 703 549-6610 The Hollinger Corporation P. Note, however, that the gloves provide less grip and special care must be exercised in manipulating the glass. Recent research has shown that the only hazard to alkaline-sensitive photographs is in the event of prolonged exposure to water. A negative which is not edge printed safety should be assumed to be on nitrate base unless positive identification to the contrary is established. Make sure that strong contact has been established between the polyester sheet, the double-sided tape, and the acid-free folder.
Mold is a serious problem that I would take major precautions to avoid. While a glass plate negative can be fairly durable and resistant to changes in temperature and humidity, it is important to follow certain guidelines for storage and handling to ensure their preservation. This is often caused by poor storage enclosures like old cardboard boxes. Polyester tape of a sufficient width should be used to entirely wrap around the edges of the package and adhere to the reverse. Labeling If your item has any kind of labeling on the container, the item itself, or any related material, we highly recommend that you return to the Basic Info section and enter this information in the appropriate field s. If using a flatbed setup, we recommend placing the glass plates onto the scanner with the emulsion matte side face-down to obtain the clearest image when using a scanner with a variable focus scanning head. The photographs should be stored vertically inside lidded boxes on the metal shelving Fig.
Selections should also be made regarding appropriate load-bearing boxes and heavy-load capacity shelving U. Quality was eventually improved, manufacturing costs came down, and most amateurs gladly abandoned plates for films. Both of these formats consist of a light sensitive emulsion that is fixed to the glass plate base with a binder. They were the first economically successful durable photographic medium. The spacers, generally small squares, rectangles or punched circles, are usually constructed of acid-free corrugated board or acid-free mat board U. The ambrotype process was popular in America from 1850 to 1870.
Two examples of vintage glass plate negatives from our collection. Early miniature cased objects including daguerreotypes, ambrotypes, and tintypes; mounted and unmounted historic and contemporary photographic prints in a variety of sizes and techniques; glass plate and film base negatives; and color transparencies may all be housed in a single collection. Melinex 516 are suitable materials for such enclosures. These protective packages were then fitted into standard-sized decorative miniature cases. The housing is constructed of pH neutral, rag or corrugated board. Gelatin chloride prints are usually warm-toned and have a reddish cast. Digitising old, fragile glass plate negatives and lantern slides is no problem for our accredited technicians, who hold years of experience scanning glass plates and understand the unique challenges they present.
After establishing the parameters for each type of image, these standards can then be applied to the entire collection. Mold will typically damage the edges of photographic material first. Enclosures for broken glass plate negatives. This documentation — in the form of field notebooks, plans, drawings, maps, photographs and slides, to name but a few — is extremely important as it provides valuable information about specimens in the collections. For example, in the 1910s, discovered as it left traces on stacks of photographic plates, which he left for that purpose on high mountains or sent into the even higher atmosphere using. The big picture: rehousing the library's glass negative collection.
Other negatives are loose or stacked on top of each other in drawers or boxes, as seen here, and the emulsions have become dirty, scratched and damaged. Retrieved May 17, 2005, from. . Warning signs: when photographs need conservation. If the intent is simply to preserve the content of the glass plate collection and allow access to it digitally, then greyscale will likely provide the clearest and most useful images.
The glass plate was then placed into a bath of silver nitrate which turned the collodion into a photosensitive silver iodide Vail, 2002, p. Many archivists believe it is better to use a larger quantity of smaller boxes than a fewer number of larger sized boxes in order to prevent strain on the boxes and any staff involved in the handling of the negatives. Many of the glues and adhesives used to manufacture plywood have a tendency to off-gas volatile organic compounds such as formaldehyde and acetic acid. This alters the appearance of the plate and presents an important question when digitising… To scan the plate in full colour, capturing yellowing and all, in order to preserve the truest representation of the archival object at that point in time. Individual plates should be placed in loosely-fitting buffered paper sleeves or four flap envelopes. Unlike the silver processes platinum metal forms an image immune to oxidation and degradation. The proper and safe storage of mounted and unmounted photographic materials incorporates several basic concepts.
Enclosures for glass and film negatives and lantern slides. Glass plate negatives present unique preservation challenges due to their fragile physical format and highly varied chemical structures. A work surface should be a clean, flat, dry table that is free of any debris. Do not treat wet collodion glass plate negatives with organic solvents, such as alcohol. Stack the protected plates inside a shallow print storage box up to 5 high. This eliminates the need for labeling the case directly and cuts down on the handling of photographs when looking for a specific one. The emulsions can be easily scratched or slip from the glass.
Gelatin bromide prints, in comparison, are often cool toned and appear black and white. The tremendous weight of a stack of glass plates places unnecessary stress on the bottom plates. Paper enclosures are available in several forms including envelopes, seamless enclosures, and folders. It is important to choose temperature and humidity levels that allow you to bring the plates from cool into room temperature without crossing dew point. Simple heavy weight acid-free folders constructed inhouse may also be used to house mounted photographic prints. Leave two additional inches at the top and bottom.