paint over the first coat. Red may be accented by placing green beside it. In fact, each of these two colors can accent the other by contrast.
Similarly when two motions occur together the contrast between them may be double-acting. When you are setting your watch, for example, the minute-hand seems to run faster, and the hour-hand more slowly, than is actually true, because of the contrast in their rates of speed. This simple law might well be applied in the movies when emphasis of motion is required. We would thus get the effect of speed upon the mind without the annoyance of speed for the eye.
One does not have to be a critic to realize that there is entirely too much speed on the screen. Some of this dizzy swiftness is due to imperfect projection or to the worn-out condition of the film; witness the flicker and the "rain" of specks and lines. Much of it is due also to the fact that the projection is "speeded up" to a faster rate than that of the actual performance before the camera. But there is also a lamentable straining for effect by many directors who believe that an unnaturally fast tempo gives life and sparkle to the action. Perhaps some of these directors have not been able to forget a lesson learned during their stage experience. In the spoken drama it has long been a tradition that actors must speak more rapidly, and must pick up their cues more promptly, than people do in real life, in order that the play may not seem to drag. But we know that the motion picture is in danger of racing rather than dragging. And racing, as we have said, hurts the eyes.
The principle of contrast can relieve the eye of a part of its work without imposing any additional task
