"Interface (1972) was Peter Campus’s second closed-circuit installation. It was presented for the first time in Europe at the Cologne Kunstverein in 1979.
The main element of Interface is a pane of glass in the form of a screen, which is placed towards the back of a dimly-lit room. The video camera is set up behind the glass and directed towards it. Facing it on the other side of the glass is a video projector connected to the camera (creating a closed circuit which instantly transmits what the camera records). The camera and projector are placed on a diagonal. The visitors, who make up an essential component of the work, are invited to walk through the space in front of the glass, which thus serves a double function: it reflects the viewers’ image like a mirror but also serves as a screen, permitting them to watch the image recorded by the camera. By means of the glass, the visitors entering the environment of Interface are thus simultaneously confronted by two images of themselves, one of which is ‘positive’—the video image—and the other ‘negative’—their reflection in the glass. While the glass reflects an image in colour with well-defined contours, the indirect, ‘ghostly’ recorded image in black and white seems more fragile, as if it were floating in space. As they move back and forth in front of the glass, visitors are led to determine the exact position where the two images overlap and it is from this point that they can actually see the splitting of their image."