Professor Stephen J. Sedgwick (active 1860’s-1880’s) was an assistant to Andrew J. Russell when Russell was the photographer for the Union Pacific Railroad during construction of the line across the Rocky Mountains. He later purchased Russell’s negatives from O. C. Smith, paymaster for the Union Pacific, and published them with his own imprint. He was also associated to some degree with C. R. Savage. Sedgwick gave lectures with lantern slides made from stereoview halves during the 1880’s. He published a book of geography and history which was accompanied by one or more boxes of his views. He also sold at least several dozen sets of views. Examples of these are "Scenes From the Union Pacific Railroad," "Across the Continent," "Date Creek and Laramie Series," a New York City Series, "Rocky Mountain Scenery, California," and of course Yellowstone. The total number of views he produced is probably around 600, all of which are pirated copies.
His Yellowstone views all have the imprint "The Rocky Mountains and Pacific Coast" on the Verso. Also, his catalog titles do not seem to match his actual titles exactly. They are all Joshua Crissman or H. B. Calfee pirate views.
Mushroom Falls, Yellowstone Park.
Great Springs, Yellowstone Park.