Dumb Question of the Day

[removed account4]

When film was very expensive, 35mm cassettes came with paper leader with all of the film stored in the cassette. Sometimes there were instructions on the leader. The leader was tapered for easy insertion of the tongue into the take up spool. When they began using the film as leader, I assume that they kept it tapered for 2 reasons. 1 was that cameras were already built that way and 2 was that it was a tiny economy measure. Remember that the leading taper creates two leading tapers when punched out for 2 rolls of film. So, the cut is 2 tapers at one punch and you have 2 rolls ready to spool.

PE

so the paper was replaced by film .. and they didn't change the way the spools were made ...
kind of sounds similar to the question "why is 4x5 sheet film smaller than 4x5" "

 

[jbbooks]

...kind of sounds similar to the question "why is 4x5 sheet film smaller than 4x5" "

Probably for the same reason 2x4's are not 2 inches by 4 inches.