For over ten years, Photograph Conservator Paul Messier has been researching the physical properties of historic photographic papers—fibers, thickness, optical brighteners, and manufacturer markings. Most recently, Messier and co-authors* have been working to objectively characterize the surface texture of papers as a means to classify individual photographs as well as collections.
Using his personal collection of over 5,000 historic paper samples along with photographs from the Thomas Walther collection at the Museum of Modern Art, New York, photomicrographs of each surface were captured using a “texture-scope” available only at the Library of Congress and the National Gallery of Art. The images were then processed to abstract the features of the paper and allow for easier measurement of the distance between each vector height (i.e. texture peak). The data were sent out to various engineering teams with the goal of creating affinity diagrams that reveal patterns of paper matches. Although each team came up with a different methodology for matching samples, they all achieved results very similar to human detection showing a spectrum of matches from the same sheet of paper, same package, or same manufacturer.
With these successful results, Messier hopes to continue collecting images to be stored on an open-access database. Eventually, institutions and collectors should be able to upload their own photomicrographs and search within the system to discover affinities across a collection. This information about the paper’s manufacture can then be applied to connoisseurship and conservation purposes.
*This project was a collaboration between Paul Messier, Richard Johnson, James Coddington, Patrice Abry, Philip Klausmeyer, Andrew G. Klein, Eric Postma, William A. Sethares, Sally L. Wood, and Lee Ann Daffner. To read more, please see the studies listed on the Paul Messier website.