Subjects were required to sit perfectly still for minutes at a time while their images were exposed onto silver-plated copper which had been polished to a mirror-like sheen before being coated with a light-sensitive silver halide. The subject’s image would be projected onto this photo-ready surface via a lens, and then mercury vapor would be introduced to develop the image on the plate. Once that was accomplished, the plate would be dipped in a fixer, which would wash away the unexposed halides.
Leaving aside the hazard to the photographer’s health of working around mercury vapor, the resulting print was extremely fragile. The solution to this problem was generally to seal the daguerreotype in a glass case, preferably one whose air had been replaced with pure nitrogen. That’s why the antique daguerreotypes that appear on the market today are always sold enclosed in a glass case, most of which are ornately framed.
Because daguerreotypes required a subject to remain immobile while their image was captured, most were shot in studios where conditions could be controlled. In 1850, Mathew Brady published a famous series of portraits called the Gallery of Illustrious Americans, one of whom was politician and newspaper publisher Horace Greeley. Another photographer, Nicholas Shepherd, got a young congressman named Abraham Lincoln to still long enough for his portrait to be captured.
Other interesting categories of antique daguerreotypes include the occupational photographs. Stonecutters, watch makers, and seamstresses are all represented. Then there was the series of daguerreotypes taken of members of the American Colonization Society, the organization that helped relocate freeborn and emancipated slaves in Africa—in 1847, the group helped establish Liberia for this purpose. More rare are exterior scenes, which ranged from pictures taken in the gold-mining camps of California to views of Niagara Falls.
In 1851, daguerreotypes were the toast of an exhibition at London’s Crystal Palace. But the labor-intensive—and dangerous—daguerreotype would fall out of favor by the end of the 1850s, eventually being replaced by the ambrotype and tintype.


My Favorite Image
Daguerreotype of woman with cross











