A colour synthesizer patch
The instrumentIn order to realise the colour part of Prometheus according to these artistic principles a totally new light instrument had to be developed. It consists of four essential elements:
- the installation of lighting equipment and projection screens,
- the filtering needed to produce the colours,
- the colour synthesizer that feeds information to the lighting equipment,
- the colour keyboard that puts this information under player control.
The development of this light instrument was done in stages. A brief description of the various elements follows in the order of their elaboration.
Light technician Jan Holsbergen adjusting the lamps
In the back of the hall, behind the orchestra, five giant columns rise up to the ceiling. In fact, these are projection screens of translucent PVC, approximately 2 by 10 meters each. Each screen is divided into 8 vertical and 2 horizontal segments, which gives a matrix of 10X8=80 light points. With three lamps for each point this results in a total of 240 lamps. This amount of light sources ensures that the lamps be kept relatively small, which is important in connection with response time. As commercial spots were found unsuitable, however, special spots had to be developed. Aluminium housings containing a 650W PAR-lamp and a dichroic filter were constructed and mounted in groups of 12 on aluminium frames that house dimmers controlled serially from the colour synthesizer. These frames hang in 5 rows of 4 behind the front screens and are fitted with frost filters to smoothen the transitions between matrix points.
Behind, a second level of projection is provided by means of a horizon screen. Normal 500W halogen lamps are used to illuminate this screen, again equipped with dicroic filters. Six of these on each frame, or a total of 120, are shining backwards.
In addition, a row of spotlights for the choir is installed with blue filters.
Thanks to the modular construction, the equipment is relatively easy to transport and to mount. It is developed in view of mobility permitting performances anywhere in the world.
Requirements for a performance
Music stand lighting and electric power have to be provided by the hall.
Details on the power requirements and minimum mounting facilities can be
given upon request.
Visual presentation of the project can be given either with the scale model in our workshop in Amsterdam or by means of a videotape/CD-ROM presentation.