How to Tell the Difference Between (regular) 8mm and Super-8mm

Super 8 has noticeably smaller sprocket holes to allow for larger images on the film.  By-the-way, the film is literally 8mm from side-to-side.

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There is a difference in the reels for the two.  The Center Hub diameter is larger on the Super 8.  Most dual 8 projectors (projectors that can play both versions) had separate or integral hub adapters.

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