Diameter of Reel Film Length When Full Approx. Runtime When Full
3 inch (7.6 cm) Reel 50 feet 3-4 minutes
4 inch (10.1 cm) Reel 100 feet 7-8 minutes
5 inch (12.7 cm) Reel 200 feet 14-16 minutes
6 inch (15.2 cm) Reel 300 feet 21-24 minutes
7 inch (17.7 cm) Reel 400 feet 28-32 minutes