On Super 8 cameras, what is the Daylight/Indoor switch for?
The Super 8 colour films are all Tungsten balanced. That is to say that the film is designed to be used under artificial lighting (not fluorescent). When using the film outside in daylight, with the switch in the sunny position, the 85B conversion filter built into the lens is in position, changing the light entering the lens to artificial light. This effectively makes the film speed about 1 stop slower, Ektachrome-64T becomes 40 ASA, whilst Ektachrome 125 becomes 80.
