Daguerreotype
It is said that Daguerre has found the means to collect, on a plate prepared by him, the image produced by the camera obscura, in such a way that a portrait, a landscape, or any view, projected upon this plate by the ordinary camera obscura, leaves an imprint in light and shade there, and thus presents the most perfect of all drawings ... a preparation put over this image preserves it for an indefinite time ... the physical sciences have perhaps never presented a marvel comparable to this one.
A further clue to fixing the date of invention of the process is that when the Paris correspondent of the London periodical "The Athenaeum" reported the public announcement of the daguerreotype in 1839, he mentioned that the daguerreotypes now being produced were of considerably better quality than the ones he had seen "four years earlier".
History of erotic depictions
The daguerreotypes were not without drawbacks, however. The main difficulty was that they could only be reproduced by photographing the original picture since each image was an original and the all-metal process does not use negatives. In addition, the earliest daguerreotypes had exposure times ranging from three to fifteen minutes, making them somewhat impractical for portraiture. Unlike earlier drawings, action could not be shown. The poses that the models struck had to be held very still for a long time. Because of this, the standard pornographic image shifted from one of two or more people engaged in sex acts to a solitary woman exposing her genitals. Since one picture could cost a week's salary, the audience for these nudes mostly consisted of artists and the upper echelon of society. It was cheaper to hire a prostitute and experience the sex acts than it was to own a picture of them in the 1840s. Stereoscopy was invented in 1838 and became extremely popular for daguerreotypes, including the erotic images. This technology produced a type of three dimensional view that suited erotic images quite well. Although thousands of erotic daguerreotypes were created, only around 800 are known to survive; however, their uniqueness and expense meant that they were once the toys of rich men. Due to their rarity, the works can sell for more than 10,000 GBP.