Building my first DIY 120 inch screen

How big of a screen do you want?

Is this to be a Screen /PJ combo for a dedicated Theater or a Family Room Theater?

Do you want exceptional results from a Screen that cost less than any option you mentioned? (...except the painted screen...)'

The Optoma HD25 is an insanely bright PJ. There is no way you should be considering any screen with a 2.0+ gain factor.

I use a 1.0 gain 106" screen with an HD33 projector, it offers around 700lumens. In my controlled light room, it's plenty bright, I have it on standard mode, NOT bright mode, and I even dial the brightness down an extra few points. It even works fine with dim lights on in the rear bar area.

Lets pretend the advertised lumens are bogus and it only does 1400lumens. That will still be very bright in a light controlled room. You will most likely be adjusting the brightness way down.

I strongly suggest you consider using RS-MaxxMudd LL either on a smoothed Drywall surface or on Sintra

At 120" diagonal, you going to have to shoot some funds into a substrate such as Sintra, as that material will be best suited for applying a higher gain, high contrast painted solution.

Where do you live? I can help source you a sheet...but it will cost approx $110.00 in most locals.

Spandex is going to absorb a lot of your Lumen output. Non-3D...no issues. 3-D however might be a bit too dim

BOC will still require painting.

So expect to spend some amount slightly over $160.00 at minimum if you cannot use an existing surface such as your wall..

You can go with whatever you can afford...but can you afford to go with something that is less than ideally suited? Mfg Screen material is not all that easy to work with, and doesn't play nice if you don't treat it like a spoiled child and do everything exactly as it wants you to. You also must accept and deal with whatever texture it has....and if something should go amiss in the build process, or afterward during use...your basically SOL and must start all over.

Your call.... but be advised that there are several Members in the Middle East who have gone this route, so your not taking any chances or breaking any new ground.

Mfg = manufacturing

There might be any one or several of items, but in the least, if it did not serve your desired purpose on a majority (...or all...) counts, it might be deemed as being "less suited".

You might go for "Gain" (HP) and discover that the Screen's texture and tendency to hot spot is bad since you have a preponderance of lumen output...even in Econo/3D
http://www.avsforum.com/t/1462479/building-my-first-diy-120-inch-screen#post_23062670

You might damage Mfg Screen material mounting it. Not much needs to be said about the economic aspect there.

Any Screen material that cost less than $18.00 sq.yd is probably going to present some issue or another. But that is just barely more qualified than a "IMO" there...admittedly...due to my own "small" experiences with that price point.

The fact to face is that at 120" diagonal, yes...you can order up and use a "White" material....and get only the type of results a White can provide. High Contrast Gray material will be too much of a detriment as far as lumen conservation for 3D apps. Besides, anything sold as High Contrast material will be more expensive.

Locating a suitable substrate is your only real challenge...and that is also solvable. The end all is this....almost nothing MFG Screen-wise you can find anywhere and ship in is going to surpass what you can accomplish by using a solid substrate regionally available, and assembling your own paint out of locally sourced items, as far as "Expense out layed per Performance gained" value is concerned..

I was getting to that. mfg (Mfg) = "Manufactured / Manufacturer"

. The latter would be prohibitive....but I'd be seriously surprised if there was not a Plastic Sheet/Panel Importer....if indeed not a actual Mfg to be found in Israel Sintra is a US-Branding of a material described as being: "Rigid Expanded PVC Foam Sheeting (6mm)

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Your welcome.

Whenever possible I try to go an extra mile for overseas AVS'ers and help them get the materials assembled to DIY their screens.
Seldom does anyone run up against an unassailable Brick Wall if one wants something special to happen.

Good luck! ......and keep us well informed. We'll be here if you need us.

yeah, yeah, yeah.

So I'm a slow typer.