A Brief History Of Photography

As it turns out, photography was really born out of chemical experimentation in back rooms, completely out of the lab setting. Early photography certainly wasn't known at the time to have been a very daring craft; however photographers were frequently handling toxic and dangerous chemicals without any safety precautions.
In the video, Art Kaplan, a particularly enthusiastic photo conservation scientist at the Getty Conservation institute, shows us some samples of early technical processes like daguerreotypes, ambrotytpes, and tintypes, along with some other more rare and interesting photographic techniques.

YouTube link
(thanks Kirk)