The autochrome process is the first successful method for producing color photographs.
In 1907 Auguste and Louis Lumiere patented the first commercially successful color process, which they called Autochrome Lumiere. It involved glass plates, a backlight, snoot and, mysteriously, potato starch.
John B. Trevor, Emily Winthrop, 1910
John B. Trevor, Mrs. Lucius K. Wilmerding, ca. 1916
J. B Trevor, Mrs. John B. Trevor, ca. 1914
Today autochromes are more fragile and few in number, almost impossible to exhibit, and largely forgotten in the history of photography.