And Another Thing: Oldest photo of a human

And Another Thing: Oldest photo of a human

And Another Thing is where we take a break from serious political stuff to stuff that is just - or at least I think is just - cool. Usually it's science stuff, but this time it's more about history.

Below is what is believed to be the oldest existing photograph in which a human can be seen. It was taken in Paris in 1838 by Louis Daguerre, best known today as the inventor of the Daguerreotype. If you look carefully, you can make out in the lower-left corner a figure of a man appearing to be having his boots cleaned. (Which means there really are two figures, but that of the person doing the cleaning is harder to make out.)

It's not the oldest known photograph, that being one of rooftops outside a window done by Joseph Nicéphorein Niépce (pronounced Neep-sea) in 1826 or 1827. That one was done with a photographic plate coated with a solution of bitumen as the light-reactive material and the exposure took so long - about eight hours - that the sun moved far enough in the sky so that the shadows point in opposite directions.

The Daguerreotype, using a mercury-vapor development process, shortened exposure times to minutes (the picture below had an exposure time of about seven minutes), making photographic portraiture possible, if still rather impractical. If you don't see why, try staying quite still for five minutes or so. This is one reason why Daguerreotypes essentially never show people smiling: That's just too hard a pose to maintain for the exposure times involved. In fact, the people in Daguerreotypes are often posed with a supporting bar hidden behind their heads to help them keep their heads still so their faces will be unblurred in the finished product. That's also why,  incidentally, the street seems to deserted: It wasn't. It's just that the other people, carriages, and the like didn't stay still long enough for the emulsion to register their presence.

Daguerreotypes help spawn professional (and, ultimately, amateur) photography but fell out of favor relatively quickly. Despite their still-unsurpassed detail, the facts that they were done on metal (making them heavy and thereby limiting their size), were rather delicate and prone to scratching, and, most importantly, were each one-of-a-kind originals with no way to create multiple copies, were drawbacks that could not be overcome in the face of the two-step negative-positive process developed by William Henry Fox Talbot in the late 1830s.

To the left is the original photograph; to the right is an enlargement of the area with the people.

Enlargement of lower-left area

Original Daguerreotype

Sources cited in links:
http://mashable.com/2014/11/05/first-photograph-of-a-human
http://www.daguerre.org/resource/history/history.html
http://www.hrc.utexas.edu/exhibitions/permanent/firstphotograph
http://akvis.com/en/articles/photo-history/niepce.php
http://www.metmuseum.org/toah/hd/tlbt/hd_tlbt.htm
http://www.dptips-central.com/william-fox-talbot.html