INVESTIGATION OF A SURFACE TARNISH FOUND ON 19TH-CENTURY DAGUERREOTYPES
LEE ANN DAFFNER, DAN KUSHEL, & JOHN M. MESSINGER
Before beginning the instrumental analysis, selected daguerreotypes were photographed with 4 × 5 black-and-white Kodak Plus-X film at 1x magnification in normal light and under short-wave illumination using a Raytech Model SW-218 UVC illuminator. A no. 8 Wratten gelatin filter was used to filter out reflected ultraviolet radiation and blue light. These photographs were made to aid in documenting the location of the fluorescing material during our analysis and to serve as a permanent record for future monitoring.
In addition, to record the fluorescence color, the plates were photographed with 35 mm Kodak Ektachrome daylight 200 speed reversal film (ED-135) using the same short-wave ultraviolet unit. Kodak 2E and CC40R Wratten gelatin filters were used as standard filtration of reflected ultraviolet radiation and blue light.