from a post in another thread:
"Paleolithic setting - thus no lens effects. I've been thinking about playing around with the FOV some more, to try to get a more "true-eye" projection going. humans have a stereoscopic field of view of about 90 degrees horizontal, but a peripheral field of view of 120 to 150 degrees horizontal. vertical stereo and peripheral FOVs are both about 90 degrees. the aspect ratio is about 3:1, depending on the shape of the face around the eye. anyone know if directx can do something like this? perhaps with letter boxing to get the desired aspect ratio, once the FOVs are correct?"
how might something like this be achieved?
in the past i've played with FOV's ranging from 30 to 120 or 150 degrees. wide fov's produce a "rolling" or "wrap over" effect at screen edges. its noticeable in skyrim, where people are wider at the left and right sides of the screen than when directly in front of the camera.
another thing i've noticed sometimes is a fisheye lens effect, apparently caused by the fact that a simple divide by z foreshortenting actually reduces the 3d distance of a point to the camera if its lying off-center.
it seems to me that a rotation towards the center line, as opposed to a translation along x or z in camera space (IE divide by z) would be the more correct way to do it. i do realize this probably means some sort of custom projection transform routine to replace the usual projection matrix part of the pipeline.