Roger Ebert has never been a friend of the recent resurgence of 3D movies. But now he's got proof that the technique is just plain broken, and certainly not worth the extra dollars charged at theaters, he writes for the Chicago Sun-Times. After trashing the 3D aspect of Green Hornet, Ebert received a letter from Walter Murch, a three-time Academy Award-winning editor who cut Apocalypse Now and The English Patient, among many others. Murch agreed with Ebert's comments on 3D, and went further—the technique fundamentally confuses the viewer's brain in a way that is anything but entertaining.
The flaw lies in the very nature of 3D: that though we focus our eyes on the screen say, 80 feet away, our visual convergence—the "depth perceiver" is fooled to believe that the film's images are varying distances away. "We can do this," Murch writes. "3D films would not work if we couldn't. But it is like tapping your head and rubbing your stomach at the same time, difficult. So the 'CPU' of our perceptual brain has to work extra hard, which is why after 20 minutes or so many people get headaches. They are doing something that 600 million years of evolution never prepared them for. This is a deep problem, which no amount of technical tweaking can fix."