**4. Chromaticity**

We often forget that all our image displays have limited color ranges. Colors in paintings, photography, cinema, videos and computer screens have a smaller gamu<sup>t</sup> than what is in nature's visible light spectrum. This is also the case in synthetic holography since the source images are computer generated; hence, the colors of a synthetic hologram derive from the standard RGB model used in these electronic displays. Still, the holographic *dispositif* will allow the artist to produce several chromatic effects synchronized with the viewer's movement. However, here analog holography seems advantageous when comparing the two processes. Red, green and blue lasers have a wider gamu<sup>t</sup> than electronic displays and other color mediums. By using diffraction in the reconstruction of the

interference pattern, the holographic *dispositif* enters a chromatic field distinct from the traditional reflective or transmissive mediums. In many holographic artworks, these interactive light and color compositions are not achievable with any other medium.

Sometimes, these chromatic compositions are on the frontier between abstraction and figuration, as seen in the works of Rudie Berkhout or August Muth. They are true chromatic manipulations of the light spectrum. The holographic space tends to objectify content and allow for intentional ambiguity; color fields become volumes that display ethereal, optical and geometrical characteristics. Again, holography becomes a distinct medium that opens on a new form of "light painting", where chromaticity is manipulated in its very foundation.
