Works of art, 1936-1969, bulk: 1936-1947

Primarily the work of David Rosen, this series illustrates the technical methods and documentation that he and Henri Marceau embraced for conservation and technical study purposes. Rosen made an extensive visual record of art objects using panchromatic film, as well as raking light, infrared, ultraviolet and X-ray photography. The resulting documentation consists of numerous prints, lantern slides, and negatives, which, along with a set of index cards, make up this series' four subseries. For each painting examined, Rosen noted on an index card the types of photography employed, the section of the painting documented, and when appropriate, the stage of restoration or cleaning it was in when photographed. Because most cards do not include notations about cleaning or restoration work, it appears that Rosen photographed the paintings primarily to record their then current condition and to support his own and Marceau's connoisseurship studies.

While some of the paintings documented are associated with the Philadelphia Museum of Art, particularly the John G. Johnson Collection of European paintings, many came from other institutions, dealers or private collectors as loans to the museum for special exhibitions. Such is the case for the extensive set of images of paintings by Daumier and Corot, both of which were the subject of major exhibitions in 1936 and 1946, respectively. Both artists also served as ideal candidates in the use of technical research since Marceau and Rosen often examined their works in their various articles and lectures. Rosen's index cards offer other explanations as to why objects not belonging to the museum are part of these records. According to certain notations, at least one object temporarily came to the museum to be assessed by Marceau, and another was photographed for Rosen's private work. It is also possible that some of the objects photographed were those offered to the museum for purchase. According to Marceau, these technical examinations were useful to the curator when considering a purchase of a work of art and determining authenticity and condition.