Digital photographs and metadata standards

          An interesting perspective on metadata can be gained by doing a little reading about it outside the library science literature. One article on data collected by climate stations states, ‘Metadata should reflect how, where, when and by whom information was collected. Ideally, complete metadata should register all the changes a station has undergone during its lifetime, composing what is called the station history’ (Aguilar, 2003, 1). This reads to me like a slant description of provenance. The article goes on to make a point about metadata that is too often overlooked in the focus on optimizing search results. ‘Good metadata are needed to ensure that the final data user has no doubt about the conditions in which data have been recorded, gathered and transmitted, in order to extract accurate conclusions from their analysis’ (Aguilar, 2003, 2). Transferring this sentiment to an archives context, good metadata can not only help a user find the materials they need but also assure them that what they are looking at is indeed what it claims to be.
          It is often said that there are three categories of metadata: descriptive, administrative, and structural. Descriptive metadata refers to metadata that ‘enables searching for images and provides identifying information… Descriptive metadata helps users find the digitized photographs’ (Ritzenthaler & Vogt-O’Connor, 2006, 399).  The quotes above would apply to descriptive metadata, and in class we often discussed metadata solely in its descriptive function. The descriptive function is obviously extremely important, but as the digital transition continues, the administrative and structural functions of metadata are going to grow in importance and utility. And as this happens, it is becoming increasingly apparent that a greater level of standardization of metadata across institutions will be needed to ensure that archives are able to continue to preserve and provide access to the images in their collections.
          The lack of a common standard for archival metadata may have been less of a problem before the Internet and digitization began turning all archives into one big archive. As Dooley pointed out, ‘Archives, libraries, museums, and other specialized institutions all have different traditions and standards (or a lack thereof) for dealing with photographic collections’ (Dooley, 1995, 85). Indeed, the fact that ‘nonspecialized standards… may not be able to account for all the pertinent metadata that should be included in an archival record’ (Skinner, 2014, 56) has long served as an argument against establishing a common standard in archives.
          If the main function of a metadata standard is held to be enhancing discoverability, the specialized functions of individual institutions may trump any arguments about the need for standardization. After all, who would know the needs of an institution’s users better than the institution itself? When it comes to archiving digital objects, however, the technical functions of metadata become more important, and the standardization of technical metadata across institutions may prove to be essential to the very survival of these digital objects. This is due to the very nature of the digital objects. The inherent qualities of digital photographs, from both access and preservation perspectives, require that good technical metadata be maintained and easily shared between institutions.
          From an access perspective, the technical metadata contains the information needed to ensure that ‘image data will be rendered accurately on output (to screen, print, or film)’ (National Information Standards Organization, 2011, ix). If two institutions sharing digital photographs are using different metadata standards, a breakdown in the translation of the technical metadata could lead to an inaccurate representation or display of an image. The use of common standards would prevent this from occurring.
          From a preservation perspective, there are two issues to consider. First, the current state of digital storage technology requires that data be migrated to new storage media every few years, which poses a risk of data loss during migration, and as digital technologies continue to change at a rapid pace, there is the risk that the technology needed to view a digital photograph will become obsolete and disappear. Both of these pose a threat to long-term preservation of digital photographs. Good structural metadata, however, can protect against both of these by ensuring the integrity of the data during migration and preserving the technical specifications necessary to view a digital photograph (Ritzenthaler & Vogt-O’Connor, 2006, 398).
          Second, good administrative metadata will be necessary to keep track of the data files containing digital photographs. A physical photograph in a single institution can be misplaced and discovered again just by looking around. A digital file that does not have adequate metadata can be misplaced and in a very literal sense never found again.
          The use of shared standards will become even more important as the use of embedded metadata becomes more common. An interesting aspect of the digital object is that its metadata can be ‘embedded’ directly in the object. This means that no matter how many copies of a digital object are made and no matter how widely it is distributed, all the key metadata for the object will go with it. The utility of embedded metadata will be diminished if the standards used to embed metadata into a digital object are not standardized (Schmitz Fuhrig, 2012).
          In many cases, standardization of metadata will simply not be useful for institutions, especially when it comes to describing photographs in ways that are most useful to their users. But, as we have seen, the rise of the digital photograph will likely require the widespread adoption of technical metadata standards if the digital photographs are to be correctly preserved and displayed. Hopefully, the fact that this metadata is connected to the inherent structure of the object and not the description of it will overcome any institutional objects to such a standard.

References

Aguilar, E.,  Auer, I., Burnet, M., Peterson, T.C., & Wieringa, J. (2003). Guidance on Metadata and Homogenization. Retrieved from https://www.researchgate.net/profile/Enric_Aguilar/publication/266866445_GUIDANCE_ON_METADATA_AND_HOMOGENIZATION/links/544127320cf2e6f0c0f60119.pdf

Dooley, J.M. (1995). Processing and cataloging of archival photograph collections. Visual Resources, 11, pp. 85-101.

National Information Standards Organization. (2011). Data dictionary - Technical metadata for digital still images. Retrieved from http://www.niso.org/apps/group_public/download.php/14698/z39_87_2006_r2011.pdf

Ritzenthaler, M.L., & Vogt-O’Connor, Diane. (2006). Photographs: Archival care and management. Chicago, IL: Society of American Archivists.

Schmitz Fuhrig, L. (2012). Three cheers for embedded metadata. Retrieved from http://siarchives.si.edu/blog/three-cheers-embedded-metadata

Skinner, J. (2014). Metadata in Archival and Cultural Heritage Settings: A Review of the Literature. Journal of Library Metadata, 14, pp. 52-68.