Hello, everyone, I am in a discussion about film lengths possibly loaded in Eyemo cameras during WWII. As most of us know the civilian hundred-foot daylight spool takes around 120 feet when filled flush to the flanges. If we had larger spools of 3.75" diameter and with a smaller hub (core) of, say, an inch diameter, we could roll on up to 180 feet. Of course, film thickness plays a major role.
Now my question, does anybody know of such enhanced-capacity film spools? ISO 3047 prescribes the max diameter of 3.62" or 92 mm. Measurements at Eyemo and Filmo cameras I have indicate that 3¾ inch spools just fit.