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Topic: Short throw solution in church
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Joined: Jan 3, 2017
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In my church I have been tasked with picking a right projector. The goal is to get a screen a minimum of 3,5 metres wide in a 16:9 ratio at 1920x1080. The projector needs to give enough lumen for the stage is pretty well lit with various lamps. It will be used for video and text projection.

The projection distance is a maximum of about 4,5 metres so I was wondering if a short throw beamer (or multiple ones with edge blending) could work for us. Is there anyone with some experience with these beamers?

We are situated in a fixed venue so the beamer will be installed and not moved anywhere.
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Joined: Mar 28, 2005
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If this is front projection, you must keep any additional lighting from falling directly onto the screen. Normal boardroom lighting requires about 80 advertised lumens, MINIMUM, for a usable 10:1 contrast ratio, per square foot of screen space.

1080p is great, but most commercial projectors are actually 1920x1200 resolution. A bit higher than 1080p, but this allows for a 16:9 or a 16:10 screen to be used. I recommend a 16:9 screen.

Your screen size is about 82 square feet, which asks for a 6,500+ lumen projector as a minimum.

Your throw distance really isn't that 'short' overall. It's more than 1.0, and while it is 'shorter', you have many options out there with projectors, that don't require you buying EXTREMELY pricey short throw lenses. Many times the short throw lenses require the projector to be dead center of the screen, which often isn't ideal.

Anyway, here's a starting point list:
http://www.projectorcentral.com/projectors.cfm?g=1&hide=0&st=1&r=16&br=5500&br=16000&c=&w_m=&ar=Wide+%2816%3A9-10%29&db=&zr=&wt=<g=&ll=&mfg=&p=&wr=&dt=&t=&pjl_m=&pjw_m=&pjh_m=&td_m=3.8&is_m=350&i=w&tr=&tr2=&oop=2&sort=%24&sz=15

I have the brightness a bit lower than recommended, so I would look at brighter models on that list.

This model, in particular, jumps out at me:
http://www.projectorcentral.com/Epson-Pro_G7905U.htm

The calculation shows that it can be as close as 3.6m lens to screen for a 3.5m wide screen.

http://www.projectorcentral.com/Epson-Pro_G7905U-projection-calculator-pro.htm?td_=12%2E467191601&id_=162%2E494748606&l_=2132

It also offers a slightly shorter throw lens which may be used which can throw that same 3.5m width from 3m to 3.7m lens to screen.

Since the projector is about 53cm deep, you should be able to use the first lens without issue.

Eiki also has a nice offering here:
http://www.projectorcentral.com/EIKI-EK-610U.htm

Which has a nice shorter throw lens which can do the size from 3.3m to 4.3m and has a depth of 45cm.

There are many good options, but I would likely avoid DLP on this as the color brightness for video is likely to be less than half the rated brightness which will not be good for your setup. UNLESS: You get 3-chip DLP.

LCoS would be acceptable as well, but the Canon REALiS may be too dim for your needs at 6,000 lumens.

I have no idea of your budget, but this request you have made is for a non-standard image size in a limited flexibility installation. It will impact budget due to these requirements and budget needs to be set accordingly.

You will need an acceptable screen to go along with this as well. I would recommend something with minimal gain and perhaps grey to help increase contrast a bit. I don't believe you will find much in the way of ALR screens at that size (ALR: Ambient Light Rejecting).
AV Integrated - Theater, whole house audio, and technology consultation during the build and installation process in the Washington, DC metropolitan area.
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Thank you for your elaborate answer! As it happens the only affordable projector in the Netherlands (where my church is situated) in the list you posted is the Canon XEED WUX6010. We will work around the distance issue and use the standard lens, at the moment it is the only one we can afford.

When you talk about a low gain screen, how low should the gain be. Is 1.0 low enough or should it be more in the range of 0.8?

Once again, thanks for you help!
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Sorry, I would look for a grey screen with 1.1 to 1.3 gain if possible. You don't want a lot of gain as that will impact viewing significantly, and you need both a boost to light output as well as the best contrast you can in the environment you are in.
AV Integrated - Theater, whole house audio, and technology consultation during the build and installation process in the Washington, DC metropolitan area.
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This is cool as I want a a screen of 1.1 to 1.3 wide with grayish color in the church.
https://www.locusassignments.com/