Light Path Details

Here are details about the light path and things to watch out for. Please add new features or correct previous entries if they could be phrased better.

Faults

• Jumping picture (vertical) - Dirty Runners - In most cases unless the gate tension is obviously loose then this is caused by dirty gate runners. The best way to cure this is the next time it is possible to stop the projector, remove the gate and the back plate and clean throughly using a cleaning solvent if necessary.

• Jumping picture (vertical) - Gate tension too loose - Occasionally in normal day to day handling of the gate, or after resetting, or training sessions, the gate tension may me too low and the picture may start jumping vertically in the gate. In extreme cases you will hear a large nasty noise coming from the gate area. The reason for this is that the gate springs are not allowing the runners on the gate to put enough pressure against the film as it travels through the gate. This means as each frame is being shown the film is not stationary, but is still actually moving. Correct this by gently turning the thumbscrew located midway down the gate clockwise until the film becomes more steady. At the next opportunity remove the gate, check it is properly clean and manually reset the gate tension.