We still tend to assume that the camera somehow mimics the eye and brain, while a projector is basically a camera in reverse, which was indeed sometimes the case in early cinema and for amateur film-makers who could adapt their cameras to project their film after processing. However, for Digital Cinema the Digital Light Projector ticks along at 144fps, whatever the official frame rate of the movie, with individual frames described as being 'flashed' more than once to fill the available time (though the very concept of 'frame rate' and 'flashing' shouldn't really be applied to 3-chip DLP's, whose 'micro-mirrors' oscillate 50,000 times a second with information up-dated in a modulated form to change each mirrors' pitch). This remarkable technical achievement is quite different to the traditional 'maltese cross' light/dark approach to match the stop/start motion of a print as it moves through the projector, or the scanned lines of a monitor. The notion of 'persistence of vision' building a perceptual bridge between one frame, or half-frame and the next need no longer apply.

Tags: Film, Digital, VIdeo, Technology