The most common methods of colouring early motion pictures were tinting and toning. Tinting was inspired by the translucent lighting gels used in theatre that washed the stage in a single glowing colour. Films were tinted by submerging frames in dye baths that saturated all the areas that weren’t black. Toning, adapted from photographic printing, coloured only the darker areas of a frame. Often, toning and tinting were both used in the one film to create moods, convey emotions and heighten tension. Other times, they were used completely randomly.
The trailer for this restoration of The Cabinet of Dr Caligari shows the tinted film frames in action.