# 16:9 90" theater screen measurements?



## nickg555 (Apr 29, 2008)

I plan to make my own 90" diagonal 16:9 aspect ratio screen using super-white seamless paper. the roll comes as 53" by 8 yards. the projector im buying says it works from 50-110" at around a 2-5 meter throw distance so i figured a 90" diagonal would fit best and probably be the clearest picture. The problem is im not sure what the measurement would be for a 16:9 ratio 90" diagonal screen.


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## yustr (Sep 27, 2004)

Nick, you mean you don't remember high school trig? 

Me neither...:grin:

Using brute force, I get a screen size of just under 79" x 44"


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## ebackhus (Apr 21, 2005)

a^2xb^2=c^2. C is the diagonal measurement.


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## yustr (Sep 27, 2004)

Yes, the Pythagorean Theorem is how I got those dimentions. 

(It's a^2 *+* b^2=c^2 not: a^2 *X* b^2 = c^2 LINK )


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## ebackhus (Apr 21, 2005)

How dare you correct my horrible memory!? I coulda sworn is was multiplication...


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## nickg555 (Apr 29, 2008)

i am a math wiz just far to busy and bombarded with college work to figure this all out on my own. im putting this screen in my room. I figured i can spend $400 for a semi-large flat screen tv. or just $300 for 3 times the size and mount a projector on the ceiling and project it on a homemade screen. i still have to figure out the exact size of the wall.. a 90" screen will fit however i also have to figure in the surround sound speakers so im going to have to take some measurements of availablle wall space.


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## GZ (Jan 31, 2010)

You don't need to build a screen if you have an even wall that you can keep clear.

Just a little surface prep work and a good paint job with special paint and viola! 

Screen wall, and you can adjust the size to suit your needs.

How to Paint the Wall for an LCD Projector | eHow.com


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## nickg555 (Apr 29, 2008)

My goal is also to make it look pretty. So im going to use white seamless paper and some 1x4 poplar to make a screen i want to frame it in and cover the frame with a silvery grey fabric. im going to take those measurements of how much room i have for the screen right now.


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## nickg555 (Apr 29, 2008)

Alright so 100" of width minus speakers and and some extra room between for look. The screen can be 78" Wide.

So i just did some calculations and a 90 inch diagonal would be just right then. It would be 78.47 wide and a height of 44.08. 

The seamless paper i plan to purchase is 53" tall and something like 5 meters long. So i can always trim off the excess height. Now i just need to calculate the amount of poplar wood im going to need for the frame i suppose.


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## gcavan (Aug 13, 2009)

edit: I guess nick is quicker with the number pad. I get 45 x 78

Actually no need to trim it if you are framing it in. Attach the sheet to the wall and let your frame cover the edges


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## nickg555 (Apr 29, 2008)

According to online sources the optimum veiwing distance for a 90 inch screen is around 20 feet... well i have 12 feet max so im thinking i might have to downsize and considering a 74" diagonal. I think that would make the screen 68x44 i came up with that measurement in under a minute so iim not sure if its right but i still have a month before i finish this project so no rushes i suppose.


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## GZ (Jan 31, 2010)

If you already have the projector, why not set it up and see what is a comfortable viewing size for you.


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## nickg555 (Apr 29, 2008)

unfortunately i dont have the projector yet. I just like to be prepared beforehand. This way i have an understanding of what i need to do so when i do get it i can have it all set up within a day or two. I will have everything by the end of next month if all goes well.


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## GZ (Jan 31, 2010)

Well, there is one other thing you can do to find a comfortable viewing size.

Go to a TV retailer and find a big TV that is on. Find a comfortable veiwing distance and measure it from the TV... Then, you can get an idea of what would be a comfortable size screen at the distance you will be watching it from.

Just an idea, to save you headache in the future... literally.


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## nickg555 (Apr 29, 2008)

I dont plan to construct the screen until the projector is here this way i can mount it to the ceiling and confirm a good screen size which the image is the best at. its only a $200 projector so i got to make it as clear as possible. i also have to make sure thhe projector is going to work right as a 16:9.. The listing states it is 4:3 native and supports 16:9 and im hoping it wont change all the time show as 4:3 with the black bars or something. I will fid the link to the projector in case your knowledgable in them this way i can hopefully make sure im not going to have to modify a screen all the time.


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## nickg555 (Apr 29, 2008)

this is the projector.

DG-737 HDMI 1080i home theater game TV LCD projector - eBay (item 270647871453 end time Feb-07-11 23:34:27 PST)


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## GZ (Jan 31, 2010)

Okay, you may have issues with that screen size... Check the documentation of the projector to find out how far away from the surface you will need to mount the projector to get the size you want... The size controls on inexpensive projectors don't adjust very far... Also, with an inexpensive projector, you may have a problem with the bulb. Projector bulbs cost hundreds of dollars by themselves.


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## nickg555 (Apr 29, 2008)

This projector the bulbss are very cheap at only around $20-30

Technical Specifications
................................................................................................................................................................................

Projection System RGB LCD Projection System 
Projection Schemes Front/Suspension 
LCD Panel 5" TFT LCD Panel 
Resolution Support 1080i/720i/576P/576i/480i，640*480（support 1024*768) 
Brightness(PeakValue) 2000Lumens 
Contrast ratio 600 : 1 
Lamp 150W 
Colors 1.67 million 
Aspect Ratio 4:3 or 16:9 
Optical Lens Manual focus 
Projection Distance 1.76 – 5.51 meters 
Image Size 50 – 150 inches (in Diagonal) 
Interface Video, Y/PB/PR, S-video, VGA, TV, HDMI 
Video System PAL /NTSC 
Audio Output 2 built-in speakers, RCA ×2 
TV Signal Input 75Ω Radio Frequency Signal Input (RF Input) 
TV Signal System PAL /NTSC/SECAM 
Mechanical: Dimension(excluding lens and feet) 
320mm(Length) ×249mm(Width) ×95mm(Height) 
Weight 4.3 kg 
projector color black (normally is Black, if you like Silver, please inform me) 
Operating Temperature 5 – 35 ℃ 
Power Supply AC 100V-140V or 200V - 240V at 50 /60HZ （ All kinds of power cords for all over the world.） 
Power Consumption
220W


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## GZ (Jan 31, 2010)

Wow... 600:1 Contrast ratio! That is a little low... Those numbers should be in the 1000's...

Here, read this article...

Video Projectors: What You Need To Know


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## nickg555 (Apr 29, 2008)

hmm i didnt consider that. Im having a hard time finding a projector with 16:9 HD ready with good contrast and resolution. Im not looking to spend over $300 im one of those who likes to get the most for the least when possible. I like these brand of projectors due to the cheap bulbs and there is also 61 reviews on ebay which is the link i provided. and there really is not many complaints. So im not sure what to do at this point.


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