Glossary Of Film Making Terms - I
Incident Light Reading – An incident light reading measures the amount of light hitting the subject. You take an incident reading with a light meter equipped with a white half-sphere which acts as a stand-in for the subject. The sphere is pointed at the camera, so that the same light hitting the subject is hitting the sphere. The other type of light reading is a Reflective Light Reading.
Infinity – The furthest distance on the focusing ring of a lens.
Insert Shot – A close-up of some detail in the scene. (Sort of like a cutaway without the “-away” aspect.)
Interlocked – Two or more devices (most commonly dubbers in a mixing facility) with motors that run in sync are interlocked. It is not quite correct to say that a sync sound camera and tape recorder are interlocked, regardless of whether they use crystal of cable sync, since the tape recorder is recording pilottone and not really running with its motor interlocked with the camera motor.
Internegative – An intermediate copy of a film, made on a very fine-grained stock, and used to make a greater number of prints than it is practical to make from the A&B Rolls.
Interpositive – An intermediate copy of a film, made on a very fine-grained stock, usually required as an intermediate step to making an internegative.
Intervalometer – A device that attaches to the camera for filming single exposures, much like an animation motor, exept that an intervalometer is capable of exposing single frames automatically, as in the technique of Time Lapse photography.
Iris – Like the iris of the eye, a valve within a lens to control the amount of light that passes through. Opening the iris permits more light to pass through the lens and closing the iris less. The degree to which the iris is open or closed is measured in F-Stops, and on some lenses supplemented by T-Stops.
I.S.O. – The equivalent of A.S.A. and I.E., just with another name, it is another way of saying the same thing. This is the least frequently used of the three, but is sometimes found on the light meter. Treat it just as if it was A.S.A. I.S.O. stands for International Standards Organization.