Maybe it’s due to my job, maybe it’s fate, or maybe I’m just being punished for something my karma did in a last life—or however that works—but when my friends are in the market for a new TV, I’m always the first one they call. And the conversation invariably plays out the same way every time: “I just want to make sure I’m getting my money’s worth.” OK. “I want the best TV I can afford.” I love to hear it. “I don’t need anything as monstrous as yours, though!” Insert the sound of a phonograph needle being dragged quickly across vinyl right here and you’ll get the gist of how this scene will play when they film my life story.
My 56-in. Samsung DLP TV, I explain, falls right in the middle of THX’s acceptable range for my room size and eight-foot seating distance. In fact, it could actually stand to be a teensy bit bigger or I could benefit from sitting just a smidge closer. “I don’t care,” I hear time and time again. “I don’t like it that big….” Beat, one, two three. “I definitely want 1080p, though.” At this point, I’m thinking that cheesy, deflated “wah-wah-waahhh” musical sound effect of old would sum up the mood perfectly. Close-up on my bewildered face, and… cut. That’s a wrap.
All kidding aside, I seem to spend a lot of time explaining to my TV-shopping friends that they’re using two very contradictory criteria to look for their dream TV. Granted, no one should be forced to live with a screen they find overwhelming, but all the extra pixels in the world aren’t going to make a difference if the flat panel on the wall across the room looks like a postage stamp stuck to a manila envelope.
Both SMPTE (the Society of Motion Picture and Television Engineers, developers of those wonderful color bars we all know and love) and THX (developers of deliciously loud logos, among other things) have developed theatrical standards for screen size that work just as well for home theater. THX standards require the back row of seats to have a 26-degree or greater viewing angle, with a 36-degree viewing angle recommended for the optimal movie-watching experience. SMPTE nearly splits the difference, with a recommended minimum viewing angle of 30 degrees.
Put away the slide rule—we at Electronic House are here to make your life easier; not force you to do algebra. Here’s a quick and dirty guide to calculating optimal screen size for your room when purchasing a widescreen TV:
For example, let’s assume you’ll be sitting 8 feet from your screen, like me. That’s 96 inches. So according to THX, you need a 52.8-inch set (96 x 0.55). You could probably cheat and get a 50-inch if you intend to watch lots of movies that keep you on the edge of your seat. To meet SMPTE specs, you would need 57.6 inches worth of diagonal screen real estate (96 x 0.60), so a 56- or 60-inch should fit the bill. And for the optimum movie-viewing experience, THX would suggest a 72-incher (96 x 0.75).
Remember however, that you may easily get into really annoying and depressive experience when you do not take the PQ (Picture Quality) considerations into account.
The calculations presented are OK under assumption of a PERFECT CONTENT and PEREFECT DISPLAY.
Anything less than perfect and your pleasure of watching will be turned into a nightmare of tracking magnificently displayed artefacts.
Reality is that prefect displays are rare if not existing. The content is even more problematic.
Yes, Blue Ray movies are perfect for most time,
but HD TV has problems and if you still want to
watch standard TV that may be real pain.
Thus, unless you use your display only as home cinema display for watching Blue Ray movies which got highest marks for their PQ, DO NOT move to the bigger size territory. Quite opposite, even consider moving down by one step. If you get 52” as ideal, consider 46”. If you get 65” get down to 58”.
Obviously, you can keep with the prefection but make it a consious well-informed decision meaning
that you will never complain “I see those small nasty artefacts which really scratch my eyes”.
“Thanks for posting this, but I hoped you would go into more detail about why 1080p doesn’t matter(unless you’re sitting 8 feet from a 60 inch plasma). The preponderance of 1080p plasmas in sizes as small as 42 inches makes me laugh. Are people ever going to sit close enough to make use of that? Probably not, and if they did, their mothers would call them and remind them to not sit so close to the TV.”
1080p matters if you view the TV from the right distance and have an eye for quality. I am a hardcore gamer and have a 40in LCD that I sit about 5 feet away from (within the recommendation). 1080p TVs as small as 42 inches are perfectly fine if you do not want a home thearter and need a high quality TV to sit close to. Many gamers, including myself, enjoy a shorter viewing distance to feel more indulged in the experience.
This sounds like an attempt to push consumers to higher end TVs, not an honest assessment. I have a 34” CRT HDTV and can easily see the difference between 720 and 1080 content. By your calculations I need to have a 54” TV to tell the difference. That’s simply not true.
I found this little viewing distance calculator a while back. It would be a great addition to the article.
Viewing distance calculator.
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Nice! And how much is the tab?
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I agree that THX reference size and viewing distance works for BLU-RAY.
If you’ve seen HDTV (even satellite and fios… highly compressed cable is a given) then you’ll get DISTRACTED by the artifacts at that size/distance.
If you do alot of tv watching, then don’t worry about going too big. As a poster said, if you’re using your display as a PC monitor, or watching blu-ray, or even playing HD games, then sure.