the light-work is located in the train station of the city of Leiden, Holland.

at night the ceiling changes color according to a color changing program, designed by Peter Struycken.

the colored light is generated by dichroid filters and HQI light.

four groups of three colored lamps are used with red, green and blue dichroid filters with a mechanical louvre system for dimming.

train stations are a very harsh environment for electronics. therefore the Siemens 80C592 based local microcontrollers of the four light groups are linked to the central computer thru the very noise resistant CAN-bus.

the ceiling still has to be painted with the right, non reflective, paint