I just read about this great tool, the Graphics Atlas, created by the Image Permanence Institute at Rochester University. The Graphics Atlas allows you to view minute details of photographic prints produced using different techniques. You can not only zoom in on the surface of an image to see the emulsion, you can also see the edge of the photo, view it under different lighting conditions (like UV), and compare views of two different processes.
(discovered via Deep Focus, from the UT Austin School of Architecture Visual Resources Collection.)
