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Topic: Rear Projection with Ulta Short Throw Projector
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Joined: Dec 16, 2013
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Wondering if anyone might have some suggestions or guidance.

What I am trying to achieve is a 14' wide 16:9 screen. The location where I am trying to install this, is in a building that is 50' by 100' used for Religious Programs. There are no windows in the building and the first row of lighting will be turned of. Everything that will be played back using this setup will be videos, no text. I would prefer a larger screen, but the ceiling height is limiting me to a 14' wide screen.

My idea is to use a Rear Projection Screen combined with an Ultra Short Throw Projector. Something like: Epson PowerLite 485W or BenQ MW870UST.
The screen will be a Rear Projection Film possibly from Carl's Place.

The distance I have from the wall, where I can mount the projector, to the screen needs to be less then 6'.

Is it wise to use an Ultra Short Projector to do Rear Projection? Are there any recommendations as to a good Rear Projection Screen or Projector? Anything I need to keep in mind that I am missing? Looking at the attached picture, is there a better approach?

Thanks for the help!!

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You need a high dispersion rear projection material and you need to understand that a typical front projection setup with ambient light looks for about 80 advertised lumens per square foot of screen space.

With a 14' wide screen, you are looking at about 122 square feet of screen space, which will NEVER receive the full 24 lumens per square foot from that projector because no projector can actually deliver the rated max lumens while delivering the best image quality on a lamp that has 500+ hours of use on it.

As it is, I haven't seen measurements for rear projection values which are meaningful.

On top of this, you need a high-diffusion screen material which can deal with the extreme angle of the UST projector. Not sure if Carl's Place has this or not, but I know DaLite has some materials recommended specifically for this type of application.

IMO, I would go with two smaller screens on the sides if possible instead of a single large screen on center. But, I think brightness may play into all of this as a huge impact to your final system.

Oh, and if the area between the projector and the screen is not enclosed and 100% light controlled/black, then your target number must be 80 lumens (advertised) per square foot as a minimum to achieve a usable 10:1 contrast ratio.
AV Integrated - Theater, whole house audio, and technology consultation during the build and installation process in the Washington, DC metropolitan area.