Distance/Screen SIze Formula?


My husband and I are debating between a 50" and a 60" flat panel television for our living room. Although the room is very long , it is not very wide and we would be veiwing the televsion from aprox.12 feet from the screen. Does 60" seem like too large a screen for that distance or can we go for it?We hate the feeling of sitting in the first few rows of a movie theatre.........hence our concern. Can anyone help?
lel
As a generall rule for standard screen(4x3aspect ratio) take the viewing distance divide by 3.5 then multiply by 12.For HD take the viewing distance divide by 1.5 then multiply by 12.These are only guidelines and you could always go slightly larger.
Ellery911, good catch. Thanks for keeping us up to date. It does get frustrating when individuals ask for help and don't even bother to follow up.
I must be the etc. part of Don's reply being that I found Chadnliz' answer humorous. But...I really don't have much sympathy for the original poster being that 2 months ago they posted an extremely vague question and then after being prompted for further details, they never once responded to their own thread.

Sure...the poster may not be a housewife...but if she's asking about screensize TWO months after the last thread she started and then ignored then she should just be asking the guy at Magnolia who gets paid to have his time wasted by people like Lel.
Donbellphd, is right on. I suspect that long time exposure to previous technological limitations has perverted our perceptions on correct screen size for the home.
It is pretty obvious I cant argue with your big brain so you win, I do feel that my "conclusion" is probably more correct then you might assume PHD or not.
Chad etc,

I think your reply is a bit demeaning to lel and to me. lel wrote that they did not like the first few rows of a movie theater, and seemed to be asking about video size to achieve an image they might find satisfactory in their living room. From what you can be deduce from her query how did you conclude whether she is a housewife, a neurosurgeon, or what?

db
gee Don I dunno, maybe it has a thing to do with the fact it is a non-member housewife who admits confusion and probably googled a question that found its way to Agon.
Chadnliz (I assume there are two of you, Chad & Liz),

If not for movies and good HDTV programming, why would someone post a query about video on AudiogoN? A query about casual viewing would be like me asking you which tube amp I should buy for listening to the news on my AM tuner. 60" at 12' is inadequate for movies or great HDTV like CSI:Miami -- I watch the program for its HD video and 5.1 audio, definitely not its content.

db
I'd look at something in the 110" diagonal size. It'll be about the same size screen you get sitting in the last row of a decent THX certified commercial theater.

Also note that on anything smaller than about 90", you'll be unable to visutlally resolve 1920x1080 HD.

Personally I've used 100" @ 11' and 50" at about 5' with good results on DVD sources.
Chadnliz, I wasn't suggesting that 107" is the "right" number, just a number that someone comes up with. OTOH, I don't think 60" at 12 feet is overkill. I have a 50" FPD at about the same distance and while it is larger than the previous 36" 4:3 TV, it is not acres bigger and I could easily live with a 60".

Best thing to do is go visit a shop with both and sit yourself 12ft away. Or put a poster or two on some cardboard and see what it looks like in your room.
I know the calculators and understand the explanations, again I say that unless it is only for a movie experience then yea 107in at 12ft away is great, but in the real world where people watch movies, and everything else on one monitor in one room those numbers dont make sense, they are overkill and thats where I think alot of folks who are not getting a unit for a dedicated theater are being misled, sometimes bigger isnt better, its just big.
I think 60" at 12' will be like sitting in a bar watching casual TV. IIRC, the SMPTE and THX numbers (88.5" and 107.4" 16 X 9 diagonal for a 12' vieiwng distance) provide the viewing angle from near the rear of a theater. I think you want the diagonal size to be at least half the viewing distance, preferably a bit larger. At 12', I think the only practical solution is front projection, and that's not practical for casual viewing given the ambient light constraints. A more practical solution is to decrease viewing distance.

It's not obvious what THX has to do with marketing monitors, except in so far as THX certification of certain components might add value. And SMPTE? It would seem in the best interest of both organizations to keep you coming to a theater.

Visit myhometheater.homestead.com/viewdistancecalculator.html for viewing distance calculators and explanations.

db
60" will be fine. SMPTE recommends 88" - this, IMHO, is WAY too big. Stick with the 60" screen and you'll be quite happy..

-RW-
I feel that some of the new distance calculations especially THX is more marketing then common sense, sure you dont have to be far from the monitor to not see the pixels as in old technology, but some of the ratios would seem a bit too much screen for alot of veiwers, in the end I think they could be doing alot of folks a dis-service by aiming them at super huge displays and sitting pretty close to the picture.....they just want to sell the biggest display possible, not the RIGHT one. Going all out for a dedicated theater and enjoying its larger then life experience is one thing, but a housewife doesnt need or really want to be 6ft away from a 65in screen with Rosie O'donnell at 10am in the morning (not that there is anything wrong with that) :)
most of the people on AVS forum seem to recommend the seating distance to be 1.5x the screen width (not diagonal I believe)..however I have read that people have elected distances as short as 1.1-1.2x sw.

maybe you should head to an AV store...move a chair front to back while viewing a large screen display and see what distance you feel most comfortable with.
I have seen several guidelines. The SMPTE (Society of Motion Picture and Television Engineers) suggests HT installations should have a 30-degree viewing angle, but that is based on horizontal width. THX recommends 36 degrees. At 12' viewing distance, 30 degrees suggests a screen size of 88" on the diagonal. At THX recommended levels, your only choice on flat panel displays would be the new Panasonic 103" (which requires "permission" from Panasonic - they send a team of people to your site to check whether you can order it; if they say yes, you can special order one (for $50k+)). I saw one about a week ago. It's beautiful, but I decided to pass :^).

Based on those suggestions, a 60" would not be "too big." This matches my experience. The viewing angle is probably "fine", and keep in mind that if you have normal (20/20) vision, newer full-HD screens will naturally mean that you can be "closer" to your screen than non-HD screens because of the fineness of the pixels.
I sit about 10' from my 61" plasma. Works for me, doesn't seem too large, and I'm not one of those types that sits in the front row of movie theatres either...

TVs typically don't come close to the field of view that you get in a movie theatre, which can be like 30-45 degrees or so. My 61" plasma has a viewing angle of about 25 degrees at 10 feet, if I do my math right...
lel_11932@yahoo.com,

I have seen formulas for screen size referenced in postings at www.avsforum.com. I take these as guidelines rather than gospel.

In my own case, I want an immersive, theater experience in my HT. I sit about 11' away from my TV and am in the process of replacing a 61" TV with a 71" set. The 61" set looked really big when I first got it, but over time it shrank! Figuratively speaking of course, but I found that I got used to the 61" screen size and eventually wanted a larger TV.

I haven't set up the 71" set yet (it just arrived yesterday), but in no way did I feel the 61" set viewed at 11' was anything like the first 2 rows of a theater. For one thing, I look directly at the screen, I don't look up like in a theater.

As an aside, I have a 50" HDTV in the bedroom. When we're lying in bed and watching the set, we're about 12' - 13' away. I find the 50" screen size more than adequate in that situation, because in the bedroom we're watching TV versus immersing ourselves in a HT audio / video environment.

Bruce
Post removed 
I know there is a formula for this, which I disregard. I sit about 12 ft. from my 65 incher. I also have a projector . The screen comes down in front of this tv. This screen is a 92 diag.---After watching HD_DVDs or a great football game in HD---going back to my 65set----IT seems small. Hey, we're all different. Step off the distance at home--then step it off at the tv showroom---using different sizes of displays and see what is to-close---for you---not somebody's opinion.