Optimum Viewing Distance for a Home Theater Experience

The Near Distance

This distance is calculated to be where you should sit to get the best visual experience from your home theater. The vast majority of film and video is recorded on 35mm film with a 50mm focal length (or its digital equivalent). This produces a perspective that is roughly equivalent to the human eye, and a field of view of 40º. The optimum distance from the TV would be that which puts your head in the apparent position of the camera, and has the TV taking up a 40º area of your view. This distance is easy to calculate if you know the diagonal measurement of your TV. Use the formula ds × 1.2 = d, where ds is the diagonal measurement of your TV screen in inches, and d is how far away you should be, also in inches. Break out your tape measure and enjoy the movie the way the director intended it to be.

The Far Distance

This distance is calculated to be the farthest away you can sit before you can no longer perceive the full detail of the TVs screen resolution. Hawk eyed viewers may be able to sit farther than this, but this makes a pretty good estimate for those of us who weren’t born with perfect eyeballs.

TL;DR

Use the formula ds × r = d, where ds is the diagonal measurement of your TV screen in inches, r is the ratio, and d is how far away you should be, in inches.

Additional Reading

Wikipedia: Angle of View
Wikipedia: Optimum HDTV Viewing Distance
THX: HDTV Setup