Kinetic Light Art: Continuous 3-Dimensional Luminous Images Produced on Rapidly Rotating Strings

Leonardo, Vol. 14, No. 3, pp. 208-209, 1981. Printed in Great Britain. 0024-094>(/8 I /030208-02%02.O0/0 Pergarnon Press Ltd. KINETIC LIGHT ART: CONTINUOUS 3DIMENSIONAL LUMINOUS IMAGES PRODUCED ON RAPIDLY ROTATING STRINGS Andy Pepper* The projection system detailed below has been developed from a previous one using geometric images on 35 mm slides projected through volumes of theatrical smoke to produce 3-dimensional light images viewed in a darkened room [13 and from work using rotating string and nylon net constructions to intercept similar images projected over distances of three to six metres. In Ref. 1, other pertinent articles concerned with work of this genre are cited. The installation for the displays consists of three major parts (Fig. 1): (1) an automatic slide projector (Kodak Carousel SAV-2000) with a small oscillating mirror: (2) Fig. 1. Two diagrams, elevation (top) and plan (bottom). showing the arrangement of equipment in the installation. The Rectangle (dashed line) indicates the zone within which the 3-dimensional images are contained. *Artist,338 GreenwoodRd.,Carlton,Nottingharn NG4 IAR. England. (Received 3 March 1980) two white strings extending under tension between a swiveling mount on the ceiling and the floor, the mount on the floor being rotated by a robust electric motor; (3) a matt black painted screen on the wall behind the rotating strings. (The screen may be omitted if the walls of the room are painted black). Twenty-seven identical sets of slides, where each set consists of three slides, are in a repeating sequence. The projection of the series is uninterrupted, because the 81 slides fill the circular slide tray of the projector. Each set of slides projected onto a flat white screen produces the three images shown in Fig.2.These images represent three Fig. 2. Three 35 mm slides used.forprojectinx planes o f light. 208 Kinetic Light Art 209 different line projections of a cube. Figure 2, top, represents the familiar Necker cube; the bottom projection can also be seen as a hexagon and the middle projection represents an intermediate stage. The three different slides are high-contrast film negative (Kodalith ortho film) made by photographing black-line drawings. The light from the projector is reflected at an angle of 45' toward the black screen by a small mirror that is oscillated from right to left and back during the projection of one slide, a span of 5 minutes, by a cam connected to an electric motor turning at one revolution in five minutes. After each return movement of the mirror, to the right, a microswitchisoperated by the cam, causing the slide to be replaced by the next one in the sequence, allowing the installation to run unattended. The distance between the projector and the black screenis 5 m. In a larger display room, where an unacceptably large image is produced, a smaller imagecan be produced by using a 70-120 mm zoom lens mounted on the projector. The two vertically stretched strings are attached 15cm apart to ceilingand floor swivelmounts. They arerotated by the floor mount fixed to an asynchronous motor rotating at 300 rpm (supplied by Crouzet Ltd., Farnborough , Hants, England). This speed of rotation is sufficiently rapid to give the illusion of a transparent continuous 3-dimensional surface, the surface of the volume defined by the rotating strings, which bow outwards slightly under centrifugal force. If the room is darkened such that the transparent 3dimensionalsurface is not visible, when the projector is turned on each of the line projections of the slideswill intercept the transparent 3-dimensional surface to produce 3dimensional curvedline images that change continuously as the direction of the projected light, controlled by the oscillating mirror, changes. The black screen is provided to receive the projected light that passesby and through thetransparent 3-dimensional surface to produce a 2-dimensional image with reduced brightness in order not to detract from the otherwise slightly dimmer 3-dimensional image. The rotating strings intercept the light from the projector 10 times per second, a sufficient frequency to cause retinal image retention and to produce what appears to be a slightly flickering cylindrical line image between the projector and the screen. The flicker can...