Cell Side: The base (Celluloid) surface of a strip of film.

赛璐珞面(片基面)：一条胶片的片基(赛璐珞)表面。

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For a century, despite the additions of surround-sound audio systems and widescreen formats, the technology was more or less -- pardon the term -- static: a strip of celluloid, a series of sprockets and light.

CNN: Film to digital: Seeing movies in a new light