Technologies used by Archilumen


Example of a 4 colors gobo


Result at Christmas 2019, on the bell tower of
the church of Andrest (65).


The projectors used develop a power of 40,000 lumens each, with a cinema-style light rendering, giving a warmer, much more natural image than a video image. The projected image is fixed, and can be changed up to seven times at regular intervals, continuously with a black closing diaphragm between images .

It can also be replaced by a dynamic visual effect: moving stars, water, snowflakes, etc. Finally, the two types of projection can be combined by superimposing the image of the projectors.

The technology used to create the images is both simple and high-tech, since the image to be projected is laser-etched on a glass plate that is resistant to more than 500 degrees Celsius. Each four-colour image is therefore composed of four laser-adjusted plates (one plate per colour, plus one for grey levels). This composition is called a gobo.


  • These floodlights are perfectly waterproof (IP55) and specially designed for long-term outdoor use, with proven reliability (9 months of continuous use in Lourdes in very harsh climatic conditions, from snow to heatwave, without defects).
  • The projectors use 2,500 W discharge lamps. Their lifetime is given for 700 hours by the manufacturer. They must therefore be replaced annually if they are used for two hours per evening, and more frequently if the range of use is wider.
  • The projectors are controlled by a DMX system for perfect synchronisation of image changes.
  • The control cabinet has a lightning protection, the clock and an automatic reset device in case of a power failure. Starting is done by simple tripping, stopping by simple electrical cut, controlled by the programmable clock. The absence of a computer system guarantees the durability of the operation of the installation. A monitoring device is provided to remotely control the operation of the main components of the floodlights.