means of expression into the artistic process. This can include architectural structures just as much as light or sound. Usually at issue is extending perception studies into the three dimensions, surpassing the two-dimensional possibilities of image media.

In the 1960s, performance is increasingly used as an apparatus for the sensory perception of space.[38] In the so-called Expanded Cinema,[39] which more or less describes everything that goes beyond usual film production and projection technologies, conventional formal languages are also broken by the extension of film into space. Often, art and technology are here linked to one another as equals; new projection technologies are tested and the audience is integrated into the event. Joachim Paech describes the utopia of this movement as «a new avant-garde with which the cinema would be extended into all areas of information and communication, the performative and knowledge, or to put it briefly, social and cultural life. On the one hand, art becomes a medium of social information; at the same time, the new media similarly carry out their task of information with artistic means, whereby information is generally identified with transformation.»[40]

«Movie Movie»[41] (1967) was such an environmental action with film that staged processes of perception as an event with many flexible components. A spatial body filled with compressed air becomes a mobile transparent projection surface formed by using the bodies of the equally mobile audience. The dynamic relationship of the individual factors like architectonic space, observer and image to one another produce a variable visual experience that stages the image as part of architecture. The extension of the experience of reality here intended corresponds to the mood of the time (in part influenced by drugs) and by integrating the observer anticipates immersive perception spaces, which are usually computer supported.[42]

Peter Weibel, himself an important proponent of the action-referential art of this period, describes the then current notion of media situations as such: «The classical film system with its basic figures and rules—projector, projection surface, sound track, director, camera, camera movement, editing machine, montage, camera position, screen curtain, etc.—was conceived as a convention that could be changed at any time, a system of variables. Instead of the projector a mirror, instead of the stream of light a cord, instead of the