Switch! Monitor! Drift! is a videotape by Steina that was made in 1976 . It is part of her Machine Vision series-a group of tapes and installations which question our assumptions of point of view, "our" visual spectrum, our sense of where we are in terms of what we see . Steina shows the tape rarely, apparently believing it to be too specialized or too long (it is the longest tape she has made : at fifty minutes it is two times as long as any of her other tapes) . As I will indicate, the tape is rich in ideas and visually pleasurable . It deserves to be seen The most imposing works in Steina's Machine vision series are the large, rotating two camera mechanisms that were built for the shooting of the tapes in the series, and then were put on display, as works in their own right, as installation pieces . These machines, particularly the Allvision devices that have been seen at the Kitchen in New York and at the Albright Knox Gallery in Buffalo, are utterly fascinating . Two cameras, aimed at a central reflecting sphere, are on a base which is rotating parikllel to the floor . The signals from the two cameras are fed to monitors which are also in the room, so that spectators can see the machine that is shooting them and see their images on the screen(s) of the monitors . Because the cameras are focused on reflections on a curved surface, the images are distorted, and because the images are reflections , there is a "backward" quality to them . Yet the images are "live," and we can see how they are made, so they are accepted by the spectator as "true ." The technical accomplishment of the machines is also striking, as understated as the images they capture and display . In terms of sheer ideas, though, in terms of discovering what we thought we knew wasn't what we saw . . . and that what we saw was much more interesting that it seemed, Steina's videotapes are the more rewarding, more stimulating accomplishments . Steina's tapes sunder the sense of the "true" in favor of the act of perception, demanding active analytic seeing rather than the passive look . In the title of Switch! Monitor! Drift! we can see the first example of this challenge . Each word has a double aspect : as a noun and as a verb . The exclamation points emphasize the verbal tendency, but also imply, by their profusion, an irony that leads one to question their apparent simplicity . Page 2 Three sections of the tape exemplify the method that infuses the whole work . Early in the tape, following a mysterious series of 3600 pans through the Vasulka's equipment-cluttered work space, Steina appears with a violin in her hands . She proceeds to play it, and as the tone changes with each different position of the bow, so the video image changes-flip-floping (to use Steina's words) back and forth between two cameras . Watching the image "played," we deduce that the bow positions control the image . Yet later in the tape, when the image again is "played," again with the sound-track changing with each flip-flop, one wonders if the sound is controling the image, or the reverse . The sound might be the image, read on a different kind of machine (an approach already performed by colleague Tony Conrad in his Boolian Algebra film) . Equally, the sound may be controlling the image, and might even be from the violin : because the image is so slowed that we can see the scans, and the sound is very base, the sound might be a "slowed down" violin. Flow the tape was "shot" is another example of Steina's method . Not until the second half of the work do we see the machine that has been used to photograph so .much of it . All of the imagery was double-exposed, either two alternating images on a switching device or two images in one frame, with a mat used to obscure one and reveal the other . The relation of the two cameras is not made clear until the moment when we see both, each rotating on its axis, both also atop another rotating platform-and both turning within slotted concave half-mirrors . Accelerating, apparently slowing, then accelerating again, the pictures we see suggest the epicyclic movements of the planets in Ptolemy's classical cosmology . The confusion could be impenetrable were it not for Steina's intervention when she thrusts her hand into the frame to throw switches on the mechansim . She does so from the direction of the spectator, but she also does so only moments after we have seen her image facing us . It is at this point that the existence of the slotted concave mirrors becomes clear, and soon after that we can deduce the nature of the machine . (although we never see it whole!) To so challenge the viewer, to move him from the position of Ptolemy to that of Copernicus, is remarkable . Another remarkable set of images can be found in the brief sequence Page 3 3 . when Steina provides us with the only close-up images of her face in the tape . Multiplied and "rippling" across the screen, as if on the surface of an electric liquid, Steina's face appears seen slightly from below. After a few seconds it becomes recognizable, attentively serious looking out of the screen in our direction . Suddenly from the right edge of the screen a form intrudes, a form that is Steina's silhouette . From the left edge another form appears, a video camera pointed toward the opposite face . The image stands like a kind of signature and then is transformed by the recognition that in silhouette we can see how the image that is facing us was made ; whether the images in silhouette are the source of the background image is not that important-they could be . What is important is the sense one also gets from looking at Nam June Paik's Video Buddha (who contemplates a video camera pointing at himself) . Video is a mirror that permits us to better see ourselves .