Around 1905, Prokudin-Gorsky envisioned and formulated a plan to use the emerging technological advances that had been made in colour photography to systematically document the Russian Empire. [...]
Prokudin-Gorsky's own research yielded patents for producing colour film slides and for projecting colour motion pictures. His process used a camera that took a series of three monochrome pictures in sequence, each through a different coloured filter. By projecting all three monochrome pictures using correctly-coloured light, it was possible to reconstruct the original colour scene.
[the process explained]
[more & more pictures]