THE CLEANING OF DAGUERREOTYPES: COMPARISON OF CLEANING METHODS
M. Susan Barger, S.V. Krishnaswamy, & R. Messier
ABSTRACT—In order to compare and quantify the effects of various cleaning methods for daguerreotypes, two daguerreotypes were made using 19th century methods on daguerreotype plates manufactured in this laboratory. These daguerreotypes were imaged with a seven-step step tablet so that relatively large areas of like exposure and apparent density could be compared. One daguerreotype was gilded; the other was left ungilded. Each daguerreotype was cut into five pieces, and one piece of each was treated in a potassium cyanide solution; one, in a thiourea-phosphoric acid solution; two, by physical sputter cleaning, a new technique; and the fifth piece was left untreated to be used as a standard for comparison. The effects of the various cleaners were determined by comparing changes in the image particle size and distribution, and the average particle number per given area, against the standard. This comparison was done using Computer Evaluated Scanning Electron Microscope Images (CESEMI), a computer interfaced scanning electron microscope system that allows for the recognition and counting of particles of specified chemistry using an energy dispersive x-ray analysis system.
2. EXPERIMENTAL METHODS