The Techniques and Material Aesthetics of the Daguerreotype

This thesis explains why daguerreotypes look the way they do. It does this by retracing the pathway of discovery and innovation described in historical accounts, and combining this historical research with artisanal, tacit, and causal knowledge gained from synthesizing new daguerreotypes in the laboratory. Admired for its astonishing clarity and holographic tones, each daguerreotype contains a unique material story about the process of its creation. Clues from the historical record that report improvements in the art are tested in practice to explicitly understand the cause for effects described in texts and observed in historic images. This approach raises awareness of the materiality of the daguerreotype as an image, and the materiality of the daguerreotype as a process. The structure of this thesis is determined by the techniques and materials of the daguerreotype in the order of practice related to improvements in speed, tone and spectral sensitivity, which were the prime motivation for advancements. Chapters are devoted to the silver plate, iodine sensitizing, halogen acceleration, and optics and their contribution toward image quality is revealed. The evolution of the lens is explained using some of the oldest cameras extant. Daguerre’s discovery of the latent image is presented as the result of tacit experience rather than fortunate accident. This thesis is the first to rigorously explain by empirical evidence how, why, and in what ways the daguerreotype process evolved. Its trans-disciplinary methodology, combining traditional research, tacit and gestural process knowledge, and laboratory synthesis refutes the speculative views of highly regarded photo historians, thus significantly correcting the historical record. Curators, caretakers and conservators are provided new material information about daguerreotypes to guide them and protect our cultural heritage, and avoid ill-informed conservation mistakes that have led to irreparable losses of the past. Finally, this work provides evidence to revise prior histories concerning Daguerre’s research and the evolution of the daguerreotype process.