Rocky Mountain Express (2011)
Rocky Mountain Express is a 45-minute IMAX film released in the fall of 2011. Directed by Canadian filmmaker Stephen Low, it features the Canadian Pacific Railway’s restored 4-6-4 H1b Hudson steam locomotive 2816. Shooting began in 2006 and continued intermittently over the next five years, primarily on the main line between Calgary and Vancouver, with the cooperation of the CPR. The film was shot in 15 perforation/70 mm film, using a helicopter and gyro-stabilized camera mount as well as a variety of engine and train mounts.
More at Wikipedia.