(Phil Lelyveld comment: Roger Ebert takes one letter from Walter Murch describing his personal experience with the vergence-accommodation conflict (the basis of stereoscopic 3D display) and projects his views onto all of humanity to make the logical leap that S3D will never work.  There is much work currently underway in the studios, among production crews and post houses, in the game development community, and elsewhere to understand how to manage this conflict for long-duration viewing experiences and avoid the issues that Walter Murch raises.  There is much academic research underway to understand how to manage the conflict relative to the human visual system.  There is also work underway to educate professionals and the general public about the usefulness of S3D as a diagnostic tool for vision problems that vision therapy may correct.   Identifying children who have vision problems that surface when watching S3D content, for example, is the first step toward helping them potentially become better students and athletes (story here).  Many of the problems Mr. Murch and Mr. Ebert mention will fade with advances in the technology (ex. better editing tools, faster frame rates, brighter lamp houses / projectors) and the art (developing the language) of S3D.  Others are generational.  As Alan Kay said, technology is what was invented after you were born.  Older people will adjust to S3D if they chose to, but kids will just accept it.)

I received a letter that ends, as far as I am concerned, the discussion about 3D. It doesn’t work with our brains and it never will.

The notion that we are asked to pay a premium to witness an inferior and inherently brain-confusing image is outrageous. The case is closed.

This letter is from Walter Murch, seen at left, the most respected film editor and sound designer in the modern cinema. As a editor, he must be intimately expert with how an image interacts with the audience’s eyes. He won an Academy Award in 1979 for his work on “Apocalypse Now,” whose sound was a crucial aspect of its effect.

Now read what Walter Murch says about 3D:

Hello Roger,

I read your review of “Green Hornet” and though I haven’t seen the film, I agree with your comments about 3D.

The 3D image is dark, as you mentioned (about a camera stop darker) and small. Somehow the glasses “gather in” the image — even on a huge Imax screen — and make it seem half the scope of the same image when looked at without the glasses.

I edited one 3D film back in the 1980’s — “Captain Eo” — and also noticed that horizontal movement will strobe much sooner in 3D than it does in 2D. This was true then, and it is still true now. It has something to do with the amount of brain power dedicated to studying the edges of things. The more conscious we are of edges, the earlier strobing kicks in.

We can do this. 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. Nothing will fix it short of producing true “holographic” images.

Consequently, the editing of 3D films cannot be as rapid as for 2D films, because of this shifting of convergence: it takes a number of milliseconds for the brain/eye to “get” what the space of each shot is and adjust.

And lastly, the question of immersion. 3D films remind the audience that they are in a certain “perspective” relationship to the image. It is almost a Brechtian trick. Whereas if the film story has really gripped an audience they are “in” the picture in a kind of dreamlike “spaceless” space. So a good story will give you more dimensionality than you can ever cope with.

So: dark, small, stroby, headache inducing, alienating. And expensive. The question is: how long will it take people to realize and get fed up?

All best wishes,

Walter Murch

Original story posted here: http://blogs.suntimes.com/ebert/2011/01/post_4.html