Daguerreotype
This was the predecessor to the modern photograph. It dated from the 1840s and 1950s, when it was super-ceded by better methods.
Daguerreotypes are the classic “old style” of photograph, which appear to be shot through a sepia or silver filter.
Why I Looked It Up
From Uncle Tom's Cabin:
It was a daguerreotype, clear and soft as an engraving, representing Eva and her father sitting hand in hand.
Postscript
In a Buzzfeed article (item #4), a picture was captioned with this:
This picture, taken in 1838 by Louis Daguerre, is the first-ever photo to have a person in it.
So, that explains the name, which makes me wonder why I didn’t look that up before.
From Wikipedia:
Louis-Jacques-Mandé Daguerre was a French artist and photographer, recognized for his invention of the eponymous daguerreotype process of photography.