Part One: Variation in Density a)The picture on each of the five screens is identical, seven second fades from black, through clear, to black again. The same fade is printed onto the optical sound track to synchronise with the picture. b)Then follow fades from light to dark. c)And from dark to light. Part Two: Intermittency Relative patterns of occlusion and exposure occupy 2 screens. Each exposure fires a stroboscopic flash of colour: yellow for one screen; blue for the other, filling the centre of both screens with colour, haloed with after-image complementaries. W.R.