Image Quality Requirements for the Digitization of Photographic Collections

Managers of photographic collections in libraries and archives are exploring digital image database systems, but they usually have few sources of technical guidance and analysis available. Correctly digitizing photographs puts high demands on the imaging system and the human operators involved in the task. Pictures are very dense with information, requiring high-quality scanning procedures. In order to provide advice to libraries and archives seeking to digitize photographic collections, it is necessary to thoroughly understand the nature of the various originals and the purposes for digitization. Only with this understanding is it possible to choose adequate image quality for the digitization process. The higher the quality, the more expertise, time, and cost is likely to be involved in generating and delivering the image. Despite all the possibilities for endless copying, distributing, and manipulating of digital images, image quality choices made when the files are first created have the same 'finality' that they have in conventional photography. They will have a profound effect on project cost, the value of the final project to researchers, and the usefulness of the images as preservation surrogates. Image quality requirements therefore have to be established carefully before a digitization project starts.