Film and Video

The word analog or analogue recording comes from the Greek, ana “according to” and logo “relationship”.

An analog or analogue signal is a continuous signal for which the time varying feature of the signal is a representation of some other time varying quantity. For example in an analogue audio signal, the instantaneous voltage of the waves. 

Digital signal differs, in which continuous quantity is a representation of a sequence of discrete values (ones and zeros). The term analogue signal usually refers to electrical signals. 

Analogue is continuous whereas digital is broken down.

Analogue recording is a technique used for the recording of analogue signals which, among many possibilities, allows analogue audio and analogue video for later playback.

Analogue recording methods store signals as a continuous signal in or on the media. The signal may be stored as a physical texture on a phonograph record. This is different from digital recording which digital signals are represented as discrete numbers.

Film can be a chemical or digital process.

When it is a chemical process a light sensitive silver halide emulsion coated on a film base is exposed to light in a camera. This creates a latended image which is made visible by emerging the film into a chemical solution which we refer to as a ‘developer’.

A movie projector is an opto-mechanical device for displaying motion picture film by projecting it onto a screen.

Digital doesn’t require chemicals. Digital images are captured using photo sensors and these images are then processed by specialised software. Prints can be made through a traditional projection or film can remain digital form for digital projection.

Analogue is referred to chemical photography to contrast with the digital process. Analogue is referring a signal whose output is proportional to the input.