I'm looking into the types of camera/film used during WW2 to determine the factors affecting colour 'translation' to B&W.
Ivan, you also mentioned looking into the types of chemicals used when developing the photos - another interesting avenue to explore.
As things stand, I got to know about 2 types of film that were in use during the war: Orthochromatic and Panchromatic. The former is insensitive to red light and hence depict red as black (or very dark grey) in the developed photos. Panchromatic on the other hand is sensitive to the entire spectrum.
I have opened this thread so that if anyone comes across any pertinent information, they have a place to share it (if they would be so kind).
I'm have taken up this project for the benefit of the scale modelling community and would very much like for you guys to be involved in its development to make sure that it's up to SSM's HIGH standards
Thanks for taking an interest!