24-09-2019, 08:30 AM
First of all, I'm not convinced this was a 'Factory service van'; I cannot envisage a situation where the Austin Motor Company would have used such a vehicle, and the original print was not an Austin production. It could just as easily have been an enterprising local dealer or service organisation. As for colour, there's virtually no way of knowing due to the characteristics of the pre-panchromatic film. I think I can safely say it was not blue, or a shade of a colour containing blue (green or purple) as blue was the only colour in the spectrum to react on the film and create a light tone on the print. It could be a red shade, but it could just as easily be, for instance, bright yellow with dark blue lettering!