[Modeldad]

The filter most likely is in the yellow to orange to red range. Yellow and orange filters were and are used often in B&W photography to deepen a blue sky. Red radically alters the image and was used in B&W cinimatography to create night during the day by blackening the blue sky.

If it is in the yellow to orange range of filters, than White 1 may actually be Yellow 1. Yellow will be very light, near white. In fact, looking at the underside of the cowl and the white theater band, I'd say it is Yellow 1>.