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After reading the XG85 documentation I came up with a throw distance of 114" for an 84" wide 16:9 screen. The formula in the documentation doesn't differentiate between 4:3 and 16:9 so do I still use the width of the 16:9 screen in the formula? Also, I have read in some other posts that it is recommended to place the projector a little closer than specified by the manufacturer. Is this correct? If so how much closer should I mount the projector? Thanks.


Gary
 

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That sounds about right, I have my XG110lc mounted at 114", being as it's liquid coupled it needs to be a little farther back.

My last XG135 was air coupled (as yours is) and I had it at 110".


Put the projector on a movable table, open the rasters nice and wide (about +80) feed it the highest resolution your going to use, and move it back and forth until you get about a 1" overscan. Measure that distance and use that as a guide for the ceiling mount distance.
 

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Kenny's right on if you have the ability to put it on a movable table. Since I practically never get involved with physical installations (that's the hard part!), I'm not usually involved with setting the throw distance, but I've been telliing people to use the figure in the book, then knock off 5% (closer).


Chuck
 

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For a 16x9 screen 84" wide you must also mount the screen 7 7/8" higher than a for a 4x3 screen, or mount projector top of green lens 7 7/8" higher then for a 4x3 screen.


Edited 11/20/[email protected]:41PST


I tried to repost yesterday, but couldn't as the forum was backing up it's databases. I meant to type lower for the screen. I then got busy and forgot to repost. Sorry!
 

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Discussion Starter #5
Quote:
Originally posted by HighTechGuru
For a 16x9 screen 84" wide you must also mount the screen 7 7/8" higher than a for a 4x3 screen, or mount projector top of green lens 7 7/8" higher then for a 4x3 screen.


The only problem with that is that it would put the top of the screen only 5" fom the ceiling. I thought that the projector would center the 16:9 portion on what would normally be the 4:3 area. Is this not correct? If the screen is only going to be 5" from the ceiling then I may have to reinvestigate a LCD/DLP projector.
 

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Gary,


I mounted my 16:9 screen using the suggested screen centerline height for a 4:3 screen (note were talking about the screen center here and not how far down the top of the screen is from the ceiling). Divide the 4:3 screen height by two and add the ceiling to top of 4:3 screen offset and this will be your screen centerline height, mount the vertical center line of your 16:9 screen at this height and your set. By keeping the vertical center of the screen where it should be you wont have to vertically offset the picture up or down from the default zero centering position later on during picture adjustments.


Once installed you can vertically compress/squeeze the 4:3 raster down to a 16:9 height. I setup my Dish6000 receiver for 16:9 display and set my HTPC to display in anamorphic mode and both display properly at this screen elevation without having to adjust the picture vertically off of the default zero vertical setting.


Make sure your back far enough to use most of the horizontal raster on the CRTs . When properly running in full time 16:9 mode you obviously wont use the full 4:3 height of the CRTs, however you will be using the full horizotal width of the CRTs.


Bottom line is that the vertical screen center height would be the same height from the ceiling regardless of whether it is a 4:3 or 16:9 screen. When you initially fire up a projector whose default settings are for a 4:3 image, that image will overshoot the top and bottom of your 16:9 screen by the same amount top and bottom, just squeeze the image down until it hits the top and bottom edges of your 16:9 screen, put your display sources into 16:9 mode and your set.


Hope this helps.


John
 

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I did a quick review of the documentation (I can send you a PDF if you drop me an email to [email protected] ) says that you are correct in you distance from screen to green lens. I also calculated the distance from the bottom of the projector to the center of the screen (The "B" measurement) and that looks to be 39", which would be about a 5-7" drop from the bottom of the projector. It is not that hard to install the unit lower if needed, as we do not want you to get a stiff neck from looking up at that image!


Send me an email, and we can discuss more.


Jeff in Detroit
 
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