ON AUGUST 19th 1839, the government of France released the patent on the Daguerrotype to the world, which made photography commonplace.
The promise of photography had been around for decades: Joseph Nicéphore Niépce had been working on his heliograph process since 1793. His problem was that his photographs quickly faded, and his oldest surviving images date from about 1825 or 1826. Starting in 1829, Niépce partnered with the prominent painter Louis-Jacques-Mandé Daguerre to further develop the heliograph process.
Daguerre and Niépce worked on the physautotype, a process where lavender oil dissolved in alcohol was applied to a silver plate to produce an image. This process required that the plate be exposed in a camera obscura for many hours. After Niépce's death in 1833, Daguerre discovered that exposing a silver plate to iodine vapors before exposure, and then mercury vapor afterwards, could produce a plate far more sensitive to light. Daguerre patented his process in 1839, and then gave his patent to the French government in exchange for a pension for himself and Niépce's heirs.
There was a boom in professional photography. By the 1850s, photography studios could be found in nearly every major city.