Daguerreotype - Invention

Invention

Since the late Renaissance, artists and inventors had been looking for a mechanical method of capturing visual scenes. Previously, using the camera obscura, artists would manually trace what they saw, or use the optical image in the camera as a basis for solving the problems of perspective and parallax, and deciding color values. The camera obscura's optical reduction of a real scene in three-dimensional space to a flat rendition in two dimensions influenced western art, so that at one point, it was thought that images based on optical geometry (perspective) belonged to a more advanced civilization. Later, with the advent of Modernism, the absence of perspective in oriental art from China, Japan and in Persian miniatures was revalued.

Previous discoveries of photosensitive methods and substances—including silver nitrate by Albertus Magnus in the 13th century, a silver and chalk mixture by Johann Heinrich Schulze in 1724, and Joseph Niépce's bitumen-based heliography in 1822—contributed to development of the daguerreotype. In 1829 French artist and chemist Louis J.M. Daguerre, contributing a cutting edge camera design, partnered with Niépce, a leader in photochemistry, to further develop their technologies.

After Niépce's 1833 death, Daguerre continued to research the chemistry and mechanics of recording images by coating copper plates with iodized silver. Early experiments required hours of exposure in the camera to produce visible results. In 1835 Daguerre discovered—after accidentally breaking a mercury thermometer, according to traditional accounts—a method of developing the faint or invisible images on plates that had been exposed for only 20 to 30 minutes. Further refinement of his process would allow him to fix the image—preventing further darkening of the silver—using a strong solution of common salt. An 1837 still life of plaster casts, a wicker-covered bottle, a framed drawing and a curtain—titled L'Atelier de l'artiste—has been claimed to be the first daguerreotype to successfully undergo the full process of exposure, development and fixation.

The French Academy of Sciences announced the daguerreotype process on January 9, 1839. Later that year William Fox Talbot announced his silver chloride "sensitive paper" process. Together, these announcements mark 1839 as the year photography was born.

Daguerre did not patent and profit from his invention in the usual way. Instead, it was arranged that the French government would acquire the rights in exchange for a lifetime pension. The government would then present the daguerreotype process "free to the world" as a gift, which it did on August 19, 1839. However, on August 14, 1839, a patent agent acting on Daguerre's behalf filed for a patent in England. Consequently, Britain became the only nation on Earth in which the purchase of a license was legally required to make and sell daguerreotypes.