Harry Ransom Humanities Research Center, University of Texas at Austinr Photographic Conservators: A Part of the Process
 

Conservator Barbara Brown examines a late-19th or early-20th-century cabinet card photograph. Viewing the photo under a microscope permits closer examination of the surface characteristics and layer structure of the image. These observations, combined with those made by the unaided eye, help identify the photographic process used. Photo: Richard Shannon, © Harry Ransom Center Conservation Department.