I found the opening sequence from the movie La Bete Humaine to be pretty fascinating, as a record of what it was really like to be in a cab of a French steam locomotive in the 1930’s.
While it was of course staged for the film, we see some fascinating procedures as the steam train pulls into Le Havre.
I have yet to watch the whole film, but it is also of interest to me since it was one of the films that influenced the Film Noir style in the 1940s and 1950s.
La Bete Humaine was directed by Jean Renoir, son of the famous French painter. In any case, it is well worth a look for fans of steam locomotives, and especially fans of French trains and the SNCF!