Intelligent Fittings

Control of conventiomal luminiares is limited to the intensity: the attributes of the beam, such as colour, shape and direction, are all set when the luminaire is rigged. With moving lights, all these attributes become controllable; allowing the operator to change the direction, beam size, colour, projected gobo, beam quality & movement. This type of luminaire gives extreme flexibilty to a lighting rig, although a significant amount of time often has to be invested in programming the changes. However, the end result can be visually very exciting and make a performance highly dynamic.

Moving lights can be considered as Moving Mirror or Moving Head units; each of which does the same job, but achieves it in a different way. The former uses a mirror to deflect the light beam produced by the unit, moving it ith two motors to provide both pan (left-right) and tilt (up-down) control. Moving head devices physically point the whole light in different directions by using a motorised yoke.

Moving mirror type units have migrated to the theatre from nightclubs, and are best suited for prolonged, fast moving lighting effects. The effect can be enhanced by uing a smoke machine to define the moving light beams in the air. Moving head devices are better used as a replacment for theatrical luminaires, allowing the position to be moved accurately during scenes or scene changes.

Use of a colour scroller system within a theatrical lighting rig can greatly increase its potential. Instead of fitting one colour filter per luminaire, the scroller allows a row of colours to be stored and wound to the chosen colour. In this way, the number of luminaires required for a particular show can be reduced, by re-colouring the light for different scenes.

The colour filters are taped together using a special heat-proof tape, with colour selection made from the lighting control desk. The type of scroller used will dictate the maximum number of colours that can be used: Rainbow Scrollers allow 16 colours, whilst the ADB Gelbus/2 Scroller allows up to 36 colour filters.

One word of warning though: scrollers can be quite noisy, especially when a large number are used. Apart from the noise of the scroll being wound backwards and forwards, some scrollers incorporate a fan to keep the colour scroll cool. When several scrollers are used, the background noise generated can become fairly significant. The Gelbus/2, however, is virtually silent in operation, making it the ideal choice when noise is an issue.

As the name implies, this type of intelligent fitting can be used to create the effects seen in nightclubs and at parties. There is a wide range of equipment available, from simple strobes to multi-colour, multi-beam units.

Each can be controlled by DMX512, although some can be operated in sound-to-light mode. In this case, several units can be connected togther with one designated as the 'master' and the rest as 'slaves'. The master will respond to audio signals from a built-in microphone, and also trigger the slave units into action. Fairly complicated-looking light shows can be achieved in this way, with no programming by the user.

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