Identifying Common Film Formats

(Source: Academy Museum of Motion Pictures)

Note: All small-gauge film stocks are safe without any flammable nitrate.

Look for soundtrack stripe opposite the perforations (optical - variable area of variable density) or on base side (brown, magnetic)
1 perforation per frame
Most common format for educational films, amateur, and student films from 1923 to the present
May be color or black-and-white; positive print, reversal-positive original, or negative; sound or silent

Undeveloped 8mm film may be found on cartridges that look twice as wide as they need to be for such narrow film. A 25-feet roll of 16mm film was exposed down on both sides, slit during processing, and spliced end to end to make a 50-feet roll of 8mm film.
1 perforation per frame (perforations are the same size as 16mm film, oriented the same way as the image)
Introduced in 1932, produced until the 1990s
May be color or black-and-white; typically reversal and silent

Look for magnetic soundtrack stripes (dull brown) on the base side of the film
1 perforation per frame (smaller perforations than 8mm and 16mm, running perpendicular to the image)
Introduced in 1965, still produced in several different formulations
Mostly color, but may also be black-and-white; usually reversal; may be silent or have sound

https://www.digidat.be/pmain/super8-8mm-film-digitization-belgium-en.htm

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