A variety of different methods have been developed over the last two centuries photography has been around. In 1824, Nicéphore Niépce developed a machine that would project an image onto a silver plate after a few days of being exposed to light. After years of perfecting his concept, Niépce and his fellow colleague Jacques Mandé Daguerre in 1832 paired their current methods with lavender oil residue to quicken the process in which photographs would develop. Now instead of a few days, they were able to see the developed image in a matter of one day.
“I must now do three things: (1) give more sharpness to the representation of the subject; (2) transpose the colors; and (3) fix them permanently, which will not be the easiest of the three.”
Nicéphore Niépce, 1816 ( http://photoquotations.com/a/512/Joseph+Nicéphore+Niépce)
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