Check out the Eastman House’s photostream, now on flickr.
My favorites are the autochromes.
Photography’s earliest practitioners
dreamed of finding a method for
reproducing the world around them in
color. Some nineteenth-century
photographers experimented with chemical
formulations aimed at producing color
images by direct exposure, while others
applied paints and powders to the
surfaces of monochrome prints. Vigorous
experimentation led to several early
color processes, some of which were even
patented, but the methods were often
impractical, cumbersome and unreliable.
After decades of wishing for a
practical color process, photographers
were thrilled when Auguste and Louis
Lumière announced the invention of the
autochrome process. The Lumière
brothers, inventors of the motion
picture camera, presented their
invention to the French Academy of
Sciences in 1904. The process used a
screen of tiny potato starch grains dyed
orange-red, green and violet. Dusted
onto a glass plate, the dyed grains were
covered with a layer of sensitive
panchromatic silver bromide emulsion. As
light entered the camera, it was
filtered by the dyed grains before it
reached the emulsion. While the exposure
time was very long, the plate could be
processed easily by a photographer
familiar with standard darkroom
procedures. The result was a unique,
realistic, positive color image on glass
that required no further printing.
George Eastman House has significant
holdings of autochromes, including over
3900 examples by amateur photographer
Charles Zoller of Rochester, New York.
The museum also holds autochromes by
Edward Steichen among others.
I vote for the Sphinx.