Reading 2

Wilhelm, H. (1993). Chapter 18: Handling and Preservation of Color Slide Collections: Selection of Films, Slide Mounts, Slide Pages, and Individual Slide Sleeves. The Permanence and Care of Color Photographs: Traditional and Digital Color Prints, Color Negatives, Slides, and Motion Pictures (pp.625-654). Grinnell, Iowa: Preservation Publishing Company.
ISBN: 0-911515-00-3

I chose this chapter as my second reading because Brad recommended it and I frequently handle slides in order to scan them as part of my internship. Since this book is written not only for archivists, but also for professional and amateur photographers and people who manage collections of images, the material in this chapter which focused on providing guidance for the selection of film was not very applicable to archivists, who have little control over the types of film that come into their care. However, the chapter's guidance on the proper storage and handling techniques for slide collections and the author's suggested procedures for creating duplicate, working copies of slides were very pertinent to the needs and concerns of archivists.

Wilhelm begins the chapter by comparing and contrasting the various slide films and mounts on the market and making recommendations for which types and brands a photographer should choose to maximize the life of his or her images. In most cases, the author recommends Fujichrome films and cardboard slide mounts. However, archivists are likely to find themselves responsible for slides made with a wide range of films of greatly varying quality and may encounter other types of slide mounts, including open-frame plastic mounts, glass mounts, and glass mounts with tape binding, all of which present their own preservation challenges. Wilhelm briefly touches on some of the issues that may arise with glass mounts, such as steam clouds between the film and the glass, and how these problems can be minimized.

The author also emphasizes at the beginning of the chapter that slides are similar to negatives in that they are usually unique originals and, as such, should be accorded the same careful treatment and handling as negatives. All "fingerprints, scratches, and abrasion" must be avoided. He notes that this is especially important when the slides will be used as a source for images reproduced in a publication, as slides in an archival collection are likely to be used, since small flaws which can be overlooked when the slide is projected will become more apparent when the image is printed.

When he discusses the preservation of slides, Wilhelm emphasizes the detrimental effects of light on all slides, which is a particular hazard when the slide is frequently projected. He recommends that even slides made with Fujichrome film, the type of film he recommends as one of the most stable available, not have a total accumulated projection time of more than five hours. According to Wilhelm, some other types of slides more prone to fading, such as those made with Kodachrome film, will begin to show deterioration after one hour of accumulated projection time. The ideal solution, Wilhelm argues, is to create duplicate, working copies of slides, and he recommends that Fujichrome duplication film be used for this process. While it seems unlikely that many archives have the resources or the need to create duplicate "working" copies of every slide in their collections, this might be an option for some heavily used slides or those made with particularly unstable films.

The author also points out that not only the light from a projector, but also the ambient light in an office can cause slides to rapidly deteriorate. Wilhelm cites a study which found that the fragile Kodachrome slides lost up to 50% of their magenta dye when exposed to eight weeks of normal office light conditions. In addition, the fading produced by leaving slides exposed to office lighting is often irregular, since slides in this situation are often stacked on top of one another, exposing different parts of the image to varying degrees of light.

However, many types of slides will fade over time even in dark storage, and Wilhelm writes that "[f]or museums and archives, where the goal must be indefinite preservation of color photographs in an essentially unchanged condition, refrigerated storage is mandatory for all present and past slide films" (625). It seems that this is unlikely to be a realistic option for all archives, however. Wilhelm also notes that humidity in slide storage environments should not be allowed to rise above 65%-70% and the temperature should not be allowed to rise above 75 degrees, conditions which are well within the abilities of most archives to achieve.

The author also provides guidance on the selection of slide pages and sleeves. Slide pages are clear, flexible holders for slides which assist in storing and protecting the slides. Wilhelm recommends that all PVC slide pages be avoided. The material can degrade, causing the plasticizers in the PVC to stick to the slides. He suggests polypropylene pages as the best option. The author also recommends that slides be further protected by placing them in individual acetate sleeves and suggests Kimac sleeves provide the best balance of quality and price.

Overall, this chapter provides a thorough discussion of the proper care and handling of slides. It includes a useful summary of the chapter's recommendations on pages 629 and 630, and the chapter concludes with lists of suppliers grouped by type of product. For instance, the chapter lists five suppliers under "Plastic Sleeves for Individual Slides." The chapter gives both a good overview of the issues related to the care of slides and also serves as a useful quick reference for the types of supplies needed to provide slide collections with the care they need.