A version of this article appeared in print on February 9, 2012, on page B5 of the New York edition with the headline: The Really Big Picture, From Pixels to Placement.

The most important thing you want to consider is how far away you will be sitting. Larger sets require a longer distance, so you can take in as much of the display as possible. A good rule of thumb is to take the diagonal measurement of the display and multiply it by 1.5. That number will tell you how many inches you should be sitting from the screen.

It should be mentioned that this 1.5 figure is subject to fervent debate in the videophile community. Some groups recommend a multiple of 2.5, while others go down to 1.2. On the one hand, you do not want to be so close to a display that you begin to notice individual pixels. On the other, you do want to be close enough that the experience is sufficiently immersive, like having your own private Imax theater in the den.

The video resolution you most commonly watch will affect this distance calculation. The higher the resolution, the closer you can sit. If your giant TV will mostly display Blu-ray discs, you can probably use a smaller multiplier, as Blu-ray content is shown at 1080p, the highest available resolution. If, however, you are mostly going to watch lower-quality transmissions (no cable network transmits in 1080p, although there is some on-demand content), you do not want to get too close and may want to go for that higher multiplier.

There is also the matter of how far up the wall you should mount a display or, if placed on furniture, how tall that should be. The truth is that most people place their TVs too high.

What you want to do is position the television so that your eyes are level with the bottom of the display, or at least somewhere within the bottom third of the display. THX, the company that creates various home-theater technology standards, recommends that a viewer’s head should not have to look up more than 15 degr