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Discussion Starter · #1 ·
Hi,


I've just received my "almost" new NEC XG-75. I'm on my 4th upgrade, I've set up a Pulsar, Zenith and Electrohome 3501. The later is the one I'm removing from service.


My question is about the distance the projector is to be set from the ceiling and the screen. I have the installation manual and it gives a few confusing figures.


My screen is a HDTV size 110" Diag. or 54" H x 96" W. I've been using it in a 4:3 format at 96" Diag. or 54"H x 80 W ( since I have not yet gone to HDTV) of coarse there is a 8" wide unused screen on each side. I don't mind that.


The problem I have is figuring the correct distances. The charts in the manual have a "Screen size H-Width" and (4:3 Diagonal) The screen width listed is 80", but the 4:3 Diagonal listed is 100". My question is should I follow that column of figures or not?


Also my ceiling to center of screen is 48", any body out there have a similar set up with a 96" diag. screen. If so what diminsions are you using? How far is the projector from the ceiling and the screen?


One more question, will the XG-75 display the HDTV format (or switch to it) and the 4:3 or will I have to move the projector when I finally go to HDTV?


I would like to thank anyone who takes to time to help me out,




Chris
 

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Hi there,


What a lot of guys do, including myself, is table mount the projector and use the moving table method.


You set the horizontal raster size so that is uses as much of the tube face as possible without extending beyond the tube edges. I like to leave at least 1/8" (Others may recommend 1/4") between the edge of the raster and the tube edge.


After setting the raster size, you then move the table to fill your screen in the horizontal direction and then set your vertical amplitude for whatever aspect ratio you are using either 4:3 or 16:9 Anamorphic. By doing this, you maximize the amount of phophor usage and therefore increase the brightness and resolution available.


Hope this helps,


Brad
 

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Discussion Starter · #3 ·
I have no choice but, to ceiling mount the projector.


If I 'm reading you right are you saying I might not have to follow the table in the manual?



Thanks


Chris
 

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Right, if you follow what is in the manual you most likely will not be maximizing the phosphor usage. Maybe someone else can chime in here, but I recall reading somewhere to mount 5% closer than what is recommended to gain the extra tube usage.


I also meant to say to table mount temporarily to determine what your throw distance will be, then go ahead and mount on the ceiling at that distance.


Brad
 

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Discussion Starter · #5 ·
I guess I'm reading to much in to what the manual calls for. I thought that the throw distance has to be set as the manual said or you might not be able to get get the best focus. I do how ever understand why you need to use all of the CRT you can. The manual even says you can go + or - 3%.


What do you recommend the distance from the ceiling for the projector and the center of screen be? Again the manual calls for angel of 12.4 deg. is that a figure that can be different and still get a good image? I'd like to have the projector as high as possible and keep my screen center at 48".


Following the manuals guide lines I'd have to mount the projector over 25" down from the ceiling. I wonder if I raised it 5" or so if I'd still get a good in focused image all around, or would the increase in angle cause part of the screen to be out.


I know the best thing to do is what the book says, but that wouldn't be near as much fun, now would it?


Thanks


Chris
 

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