Although some archivists debate the necessity for item-level access, it is often more challenging to describe images in the aggregate. Collection-level description can be useful for images of the same subject, but problematic for collections with a variety of subjects, as it neither improves retrieval nor limits the handling of the originals. Group arrangement and description are necessary for large collections or when resources are limited.
The Sum is Greater Than its Parts
Collections can be accessed as a single unit or organized intellectually under a sole classification while being physically stored or electronically displayed in separate groupings. Archival collections tend to be characterized by a coherence that binds the contents together and, as a result, a totality enhances the research value of each item beyond what it would have in isolation.
Archivists can evaluate the appropriate description treatment for a given group of materials: whether the items should be cataloged at the item or collection level. They can create catalog records and finding aids, frequently using a combination of description levels to facilitate access. This blended approach allows control over the holdings at the collection level, as well as specific control over individual assets at the item level. This method is especially important for high-demand items, items used in exhibits, or items with high intrinsic or market value. Evaluative methods should be used to determine the level of description required.
The literature about subject indexing of images, especially, emphasizes the need for greater access at the primary subject level of description. Description generally concerns an image’s secondary subject matter. This means that a user must have a certain amount of specialized knowledge to find an image. Anyone searching a collection of images accessible only by secondary subject matter is at the mercy of the indexer’s interpretation. Additionally, one cannot search across a collection for basic attributes.
Given the interdisciplinary nature of research, it is desirable that a collection of images be searchable by anyone and for a variety of purposes. In many institutions, however, retrieving an image requires knowledge of its creator or its title, supplied by either the image creator or the cataloger. Often, only collection-level descriptions are available. This means that image construct queries are simply not possible, and the user must either have specialized knowledge or rely on the memories of the individual collection managers. Describing images by their primary subject matter preserves information that both specialists and non-specialists can use to gain access to the collection.
Access to analog image collections is usually provided through finding aids, which only include subject indexing for large collections, if at all. In my experience, the most frequent approach to image retrieval is by subject. With historical photograph collections, subject descriptors were by far the most commonly used term, while words indicating place, time, and proper names were next in importance. Regardless of the resources involved, without subject access, many requests for images could not be answered. The overwhelming majority of the users who seek images by their subject indicates the importance of these terms for retrieval. Any amount of subject indexing, even of only the main subjects of photographs, can only improve access.
Whatever the depth of subject description chosen for images, the indexing of images should accomplish two things. First, the indexing of images should provide access to images based on the attributes of those images. Second, the indexing of images should provide access to useful groupings of images, not simply access to individual images.
The Depth of Description
When devising indexing schemes or indexing images, it is necessary to decide which attributes need to be indexed, which can be simply noted in conjunction with images, and which may be left for the searcher for the images to perceive. That is, it is necessary to determine which attributes are needed to provide useful groupings of images, which attributes provide information that is useful once the images are found, and which attributes may be left to the researcher to identify. However, practices vary considerably, depending on the repository, the resources available, the size and requirements of the collection, and user needs.
Ultimately, the needs of each institution must be addressed in determining the depth of description required for their holdings. As with all collections, seasoned archivists will evaluate the best level of description needed to make their collections accessible to users.