FWIW an A4 sheet of Baader will make filters for 100mm refractor, set of 10x50 binos, 8x50 finderscope and 6x30 finderscope, at least. It costs $45 + delivery (~$6 ) so there really is no excuse. The film also comes with directions for constructing the filter frame out of cardboard, or else there is
Iceman's how to here.