[plaiming]

I just mounted my 1031q on a custom celiing mount very similiar to Krynos DIY ceiling mount:

http://www.avsforum.com/avs-vb/showt...=ceiling+mount


Heres my problem. I measured my projection wall and marked dead center. I also marked dead center on the ceiling where the PJ is hanging. After hanging the PJ we adjusted it so that its centered with the ceilling mark. After leveling, I projected a DVD through my HTPC. However the screen is off-center on the projection wall a couple inches.


My question is how can i tell if the front of my PJ is dead on straight and parallel with the projection wall?


Im pretty certain my mount is straight ( i measured several times, and again after i put up the mount) however, the ubolts could cause some angling one way or the other of the PJ. If i get up there and angle the projector by hand, just a slight movement really moves the picture.


One thing i didnt do is try the internal crosshath or grid pattern. it could be that my extron box is shifting the image out of my HTPC. Ill check that tonight. However, if that is still off then i know its either my PJ or the convergence is wacked so that i need to horizontally move all 3 over to center the picture.


-paul

 

[DaGamePimp]

Paul ,

-- measure from the sides of the outer lenses to the outer corresponding corner of the image for each side [ this distance has to be equal ] .

--- Jason Berg

 

[ErikS]

Take a measuring tape and measure from the upper right corner of the screen to the front right corner of your proj, then do the same on the left side. If they are the same make those measurments again but measure to the back of the proj instead of the front. Hope this helps.

 

[plaiming]

hmmm....with the HTPC, measuring from upper right corner of image to upper right of PJ there is a 1" difference between the upper left->upper left PJ. when i flip on the grid pattern, the difference is about .25" the other way???? whats up with that?


Another Oddity:

the image width of my HTPC desktop is ~82". The grid pattern is measuring about 88" width???


Ahhhh!!! Whats going on?


-paul

 

[Vic C]

You CANNOT use the internal pattern when your using the RGB inputs.


Also note, the RGB input and SHIFT control under the rear flap to see if your image is not shifted to one side or the other.


The internal pattern will be larger then the actual projected screen size from the external source through the RGB inputs. Dont ask me why. I am running an external linedoubler through the DB25 and use THX optimode disc to do convergence. If I use the internal hatch it blowes past my screen and onto the wall. The internal pattern is good for center converging but thats about it.

 

[KennyG]

Several things to consider here.

First pj centered on screen...measure from the front chassis edge, center point of the pj, to the center of both, the right and left edge of the screen, they should be within about 1/8 inch.

Second measure from the Right front corner of pj's chassis (NOT the lense) to Left center edge of screen...then do the opposite Left front corner to pj, to Right center edge of screen (use tape on screen frame to mark the spots you measure to)

Item one will tell you if the pj is centered on screen, item two will tell you if pj is square to screen.


Third, is the image centered in your Rasters? I have yet to own a pj that has the image centered in the Rasters at the default settings. You will probably have to shift the image one way or the other.

 

[Gatherer]

Quote:

Originally posted by plaiming I just mounted my 1031q on a custom celiing mount very similiar to Krynos DIY ceiling mount: http://www.avsforum.com/avs-vb/showt...=ceiling+mount Heres my problem. I measured my projection wall and marked dead center. I also marked dead center on the ceiling where the PJ is hanging. After hanging the PJ we adjusted it so that its centered with the ceilling mark. After leveling, I projected a DVD through my HTPC. However the screen is off-center on the projection wall a couple inches. My question is how can i tell if the front of my PJ is dead on straight and parallel with the projection wall? Im pretty certain my mount is straight ( i measured several times, and again after i put up the mount) however, the ubolts could cause some angling one way or the other of the PJ. If i get up there and angle the projector by hand, just a slight movement really moves the picture. One thing i didnt do is try the internal crosshath or grid pattern. it could be that my extron box is shifting the image out of my HTPC. Ill check that tonight. However, if that is still off then i know its either my PJ or the convergence is wacked so that i need to horizontally move all 3 over to center the picture. -paul

Never seen a sony 1031


Not sure what your saying but when you installed the pj and all measurements correct did you project the cross hair pattern with no input to the Pj and did it line up

Next hopefully you did a full converge

Now if you done all this

you connect to an input source now project the cross hairs again if they are dead centre the problem is


my assumption is that the picture needs to do a RGB shift to align the picture to the screen

then you may need to resize your image if it is over scaned


If the cross hairs do not match after input source I would check all measurements again also chech to see if the cross hairs are centred on the rasters

 

[plaiming]

ok guys, thanks. what you are saying makes sense. unfortunately, im out of town until wednesday, but as soon as i get back, i'll check the RGB shift. Yes, I believe if i projected the INTERNAL crosshatch, it would be very close to dead center and i could make some small adjustments to the PJ to fix . its just that the internal patterns seem to be way off from the RGB input image.


VR - I understand that the internal grid doesn't help me much for doing convergence when using the RGB input, but cant i use it to tell if the projector is aligned properly with the wall?


KennyG - Ill check on the measurements you suggested.


Thanks for the great responses everyone!!!


-paul

 

[plaiming]

well, im still having trouble centering the RGB image. I got my PJ ceiling

mount more stable and secure. When i pull up the internal cross or grid, the

pattern is centered nicely with the center line of the projection wall

and the projector. BUT...when i switch to the RGB2 input from the HTPC, the image (16:9 aspect) is shifted off center quite a bit. Now i used the RGB Shift to center it in the rasters and push it best i could, but it wasnt enough. At certain point, it stops and you start to lose part of the image. However, I did do the measurements KennyG suggested and they came out pretty much right on. I tried shifting the image using the Horizontal adjustment in my Extron box which feeds the HTPC signal into the RGB2 input, but this has the exact same affect as the RGB Shift. So the best I can do is get the picture about 4" off center.


My best guess is that maybe there is an RGB horizontal pot somewhere that's off and widening the image. Im at a 131" throw and my internal grid image is about 87" wide and the RGB2 feed is about 84". PJ Calc and the manual say i should be at about 81" wide. ( i dont know if this means the internal grid pattern or the RGB input) If i can use the pot to shrink the horizontal size to what it should be, then maybe i can shift the image a bit more to center it.


Does anyone know of such a pot?


-paul

 

[Leszek]

Paul,


I'm new to the CRT projectors, just got mine, not even installed it yet. But I've been using my HTPC with a RPTV for some time now.


You have mentioned that your image is off, when you display it from your HTPC. Do you use Powerstrip 3 on your HTPC? Do you use custom resolutions? When I set my HTPC to display on the RPTV, the positioning of the image on the screen needed some adjustments, which can be done easily through the Powerstrip.


When you connect any other source, like a regular DVD player, does the image display correctly or is it shifted the same way as from HTPC? Maybe all you need is an adjustment of the display through the HTPC?


Regards,

Leszek.

 

[plaiming]

Leszek,

thanks for the reply. what PJ did you get? Yes I have powerstrip installed but im not really using it. Im just sending a 640x480 res from windows xp to my projector. I havent tried using powerstip to move the image but i think it will have the same affect as using the rgb shift. it will just shift the image within the rasters, but that doesnt seem to be enough. unfortunately, i dont have any way to hook up a regular DVD. All ive got is my HTPC or the internal grid patterns. The internal grid patterns are dead on. The RGB2 input seem way off.


-paul

 

[Leszek]

Paul,


I've got Ampro 4000G from Curt. Unfortunately, it's still not installed. I'm having a major construction going on in my apartment now (yes, I live a second floor apartment, with an 8 foot window in my living room, and still hope to set a nice home theater there), replacement of the entire washroom, including all plumbing, fixtures, walls and even bathroom floor. Hopefully next week I'm going to regain the use of washroom facilities .


I know it may be different with your projector, but I played quite a bit with the Powerstrip to have my HTPC display properly on my Toshiba TW40x81. Even the standard windows resolutions, like 640x480 can be tweaked to your heart's (or projector's) desire through the Powerstrip. You can play with scanning rates, porches and synch widths to match the HTPC output to whatever your display needs.


If you click on the PS icon and go to: Display Properties> Configure> Advanced Timing Options, you will see all the values of scanning frequencies, mumbers of active lines, front and back porches and synch widths. Moving the entire picture sideways or up/down is as easy as clicking on the arrows. You can also change the picture size (shrink or expand, horizontally and/or vertically), but this process changes the scanning frequencies, so if you want to keep the frequencies at any certain values, you have to compensate the adjustments by changing the individual values for scan rates and/or porches and synchs. It's more difficult to explain than to actually do this, so when you start playing with this you should get the idea pretty fast. Just pay close attention to which values change how much when you click on any particular button.


You can also set your custom resolutions (provided you have a suitable display card and a driver which allows that), by choosing one of the pre-programmed resolutions (plenty of these available) or making your own (I'm currently running 896x504 on the Toshiba, but with the Ampro I'm planning to go for 1440x960). You can set exact numbers of lines, porches etc., effectively making your HTPC better than any line multiplier.


Try it, and good luck.


Leszek.