As far as I remember from photography classes, the only colour film available was slide film. Transparency film was expensive to print to paper. All professional photographers used black and white film, even those who were on film sites for publicity purposes.
They shot in B&W and the images were hand-coloured without being able to resort to the finished product (the film) because it wasn't yet a finished product. (Technicolor itself involved the use of a red film, a blue film and a yellow film, which were combined in processing to produce the onscreen images.) In the B&W photography notes were taken as to the colour of the items worn, hair and eye colour of the subjects of the photos...but great artistic license was taken at times.