[Update: We're all buying 4K TVs now and the rules have changed. Check out our Which size 4K TV should I buy? feature]
When you’re in a retail store looking at the giant lattice of televisions, it’s inevitable that the bigger screens will be the ones that catch your attention. When put side by side, who would want to look at a 42in television when there’s a 65in towering above it? But in your living room, you won’t have a wall of televisions (unless you’re really lucky) — you'll have one. And if it’s not the right size for your living room — not too small, and not too big — you won’t get the perfect viewing experience. Here are a few tips to ensure you choose the right TV for your home.
The rule of thirds
At the very most, the distance you sit from your television should be three times the TV’s diagonal screen size. So, for example, if you’ve got a 32in (~82cm) television, don’t sit more than 96in (~244cm) away to maintain that immersive feeling.
This isn’t a hard and fast rule — some people maintain that you shouldn’t sit more than twice the diagonal screen size away. For optimum viewing, THX recommends sitting only 1.2 times the diagonal screen size away.
Sitting in your favourite spot with the television in front of you, you should be able to look from one horizontal edge of the screen to the other in under forty degrees. If you sit too close, you’ll have to move your head to watch action in separate corners of the screen, causing eye and neck fatigue.
For a demonstration of this effect, head down to your local cinema and pay $10 for a ticket to the latest action movie. Make sure it’s not a very good film — because you’ll be shuffling around during the screening. Sit in one of the front rows and you’ll have to crane your neck from left to right to see the characters on-screen. Sit right up the back and you’ll lose that immersion. Find a comfortable middle ground and you’ll enjoy the film more — it’s the same with a television in your living room.
If you’re between 1.5 and 3 times the diagonal screen size away from the television, you’re probably OK.
Check your angles
For optimum viewing, the television screen should be positioned in your living room to directly face the position from which you'll most frequently be watching it. If you sit half the time on your couch and half the time at the dinner table, pick one location and point the screen towards it; compromising between the two will degrade picture quality in both locations.
Screen height is also important. Most entertainment units and coffee tables are low to the ground, but you should have the centre of the television screen aligned with your line of vision when you’re in your favourite spot. You can do this by buying a larger screen, getting an after-market stand or, if you’re short on cash (why are you buying a TV again?), using a couple of phone books. This way, you’ll save yourself fatigue from constantly looking slightly up or slightly down at the screen.
Taking a television back to the store is a hassle. They’re heavy, bulky and fragile, and the store might charge you a restocking fee for your trouble. That’s why you should ensure you’ve got the right measurements to save yourself money and distress.
Try folding a bed-sheet to your desired screen size and sticking it to your wall for a few days. This is only a rough approximation — it doesn’t have moving images on it, for one thing — but it allows you to gain some idea of what the television will look like on your wall.
Once you’ve figured out a reasonable size for a television, go into the store and choose an appropriate model. If several different sized fall within an acceptable range — say, 47in, 50in and 52in — remember that a bigger screen will be more immersive (to a point) while smaller screens are often significantly cheaper.
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