Fuji IT-N is a C-41 internegative film for making negs from slides with 3200 kelvin tungsten lights. Does anyone know approximately what ISO might work in a camera for mis0using it? I have a datasheet and it gives a typical exposure (10 seconds) with an enlarger, but I didn't see an f-number. Apparently some Kodak printing lenses were similar to point-source lenses wide open, like f/4-ish. Does any of this add up to an ISO?