16 mm

A soundtrack is a recorded audio signal accompanying and synchronised to the images of a book, drama, motion picture, radio program, television program, or video game; colloquially, a commercially released soundtrack album of music as featured in the soundtrack of a film, video, or television presentation; or the physical area of a film that contains the synchronised recorded sound.

In movie industry terminology usage, a sound track is an audio recording created or used in film production or post-production. Initially, the dialogue, sound effects, and music in a film each has its own separate track, and these are mixed together to make what is called the composite track, which is heard in the film. A dubbing track is often later created when films are dubbed into another language. This is also known as an M&E (music and effects) track. M&E tracks contain all sound elements minus dialogue, which is then supplied by the foreign distributor in the native language of its territory.

A lens mount is an interface – mechanical and often also electrical – between a photographic camera body and a lens. It is a feature of camera systems where the body allows interchangeable lenses, most usually the rangefinder camera, single lens reflex type, single lens mirrorless type or any movie camera of 16 mm or higher gauge. Lens mounts are also used to connect optical components in instrumentation that may not involve a camera, such as the modular components used in optical laboratory prototyping which join via C-mount or T-mount elements.