you should find some red celophane and put it over the window so you don't have to tape it up. Alternately, the black backing paper on film is actually pretty light tight, if you find a deep shadowy place where you can lift the tape in relative darkness and only have it up enough to see the numbers go by as you wind, it will work.
but red clear celophane is your best bet. local hobby shop will have yards of the stuff.
Last edited by summicron1; 01-03-2013 at 12:42 AM. Click to view previous post history.