Dr. T: why 3-D's a headache

[P3D Michael Kaplan <mkaplan@xxxxxxxxxxxxxxxxxx>]

Yes, we *have* talked about this on occasion.

Classic 3D photography does things the eyes don't do. Even with 'perfect'
alignment and separation of the images, they might give headaches, though
I've never read scientific evidence to this effect. First, 3D photography
separates convergence and accomodation (focus). That means the eyes
converge on an image that is, say, 6 feet away, yet focus on the screen
which may be, say, 20 feet away.  Or vice-versa.  Likely to cause a
headache? Second, our eyes are asked to converge on that same image at 6
feet, taken by camera lenses that don't converge at all. So there's a
certain 'mistracking' that occurs.

Some viewers may have a certain tolerance to these effects, while others
may develop headaches.
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Michael Kaplan
Professor of Architecture Emeritus
University of Tennessee, Knoxville
mkaplan@xxxxxxx


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