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post #1 of 8 Old 11-16-2012, 09:26 PM - Thread Starter
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So I am about to mount 2 LG PA70Gs on my ceiling for a dual screen setup. I want to run both in 4:3 (side by side). My wall is 162" wide, so if my math is right, each screen/projector will be 81"W by 60.75"H (since I want to stretch the entire length of the wall). Now I have 3ft tall floor speakers that will be under the screen, so the screen\image should fit PERFECTLY (stretching to the corners/ceiling of the room), although im worried it might be a tad high, hopefully people will be sitting far back enough not to hurt their necks...

Anyway, given the above dimensions, how do I calculate where to install my ceiling mounts? I imagine I could get ok results by just eyeballing it, but I would rather be perfect. Also, will I lose much clarity/resolution the more I 'tilt' the projector? In other words - is it ok if the projector is HIGHER than the center of the screen? I mean it cant hang too low, or people would bang their head on it, but just curious...

Thanks
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post #2 of 8 Old 11-17-2012, 02:59 AM
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Maybe a newbish question but...

PA70G's native ratio is 16:10. If you project 4:3 wouldn't it add black bars left/right that would overlap with the other pj's projection?Or do you use some kind of lenses?
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post #3 of 8 Old 11-17-2012, 05:51 AM
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Many people (including myself) will mount projectors at the top of the screen height and have the lense shift downward.

I don't know the total specifics of every projector, but in my best setups - I've tried to mount the lense directly in the middle of the projected image - so no lense shift (vertical) is required. I try to shy away from horizontal lense shift in any situation, if at all possible. Most people do not have their projectors mounted in the middle of the image, as they would bang into it. You can get it close though (within a 1.5 ft or so). It's probably behind your seating anyway.

You usually don't "tilt" your projector. You mount it completely level, and use manual or electronic circuitry to move the image up and down.

Finally, if you want to give us a reason for using 2 projectors - I'm guessing it's because you want a super large image. You will probably need some edge blending software. I would visit Wide Screen Gaming Forum (WSGF.com) for more information. I frequent there, trying to figure out how to do a 2 or 3 projector installation as well (for super wide/eyefinity gaming).

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post #4 of 8 Old 11-19-2012, 05:26 PM - Thread Starter
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Quote:
Originally Posted by Ritzakis View Post

Maybe a newbish question but...
PA70G's native ratio is 16:10. If you project 4:3 wouldn't it add black bars left/right that would overlap with the other pj's projection?Or do you use some kind of lenses?

Crap I didnt think about that.. am I not going to be able to do two side by side 4:3 images? Couldn't I just put a cover over the lens so I don't get the side bars?

And yeah, I the purpose is to get a super large image. Two 16:9's side by side would be too long/narrow, thats why I was thinking two 4:3 would be better..

I am still concerned about getting the two images to line up... I mean I need to mount these things into studs/rafters in the ceiling, so how am I supposed to get them lined up if theres no rafter where the projector needs to go?
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post #5 of 8 Old 11-20-2012, 05:33 AM
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You will also need edge blending software, you're going to see the line between them.

You could also project in portrait mode (rather than landscape) - I'm not sure if every projector would support that - check into it. Basically that'd give you a taller image, I think the aspect ratio will still be messed up though.

There is a community out there who does do two 16x9s or 3 16x9s side by side, for those wider images - racing simulations and flight simulations.

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post #6 of 8 Old 11-20-2012, 02:14 PM - Thread Starter
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Just found this for edge blending...

http://www.edge-blending.com/index.htm

Looks like it does EXACTLY what I need, but its 800 bucks! Anyone aware of any alternatives?
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post #7 of 8 Old 11-20-2012, 07:17 PM
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I was going to use warpalizer. It's stlil expensive, but I think it's cheaper than 800.

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post #8 of 8 Old 11-20-2012, 09:32 PM - Thread Starter
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Hmm seems like a lot of people are using "warpalizer". Lots of youtube videos, so how much is it? can you post a link I googled but cant find where to buy...
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