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Raster and Image centering

 
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Dgeorge



Joined: 17 Aug 2007
Posts: 30


Posted: Wed Oct 03, 2007 3:26 pm    Post subject: Raster and Image centering

Hello all,

After being out of service for the summer (pj memory got corrupted and lost all its settings), I am in the process of setting my XG75 up again. Last time, a friend of mine set it up for me but I am going to try and do it myself this time.

After having problems with powering it up, the problem seems to have been fixed by reseating the system board.

First question I have is about centering the image. Once the raster is centered and maximized, how close to the margins of the raster should the image be? Should the image go right to the edge of the raster or should there be a margin between the raster and the image? If yes, how much margin?

Thanks,

David
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dbaisey



Joined: 09 Mar 2006
Posts: 821
Location: Southern Cal LA / Seattle WA

Posted: Wed Oct 03, 2007 10:49 pm    Post subject:

Have you read the XG sticky in this section? Doug
https://www.curtpalme.com/forum_archived/viewtopic.php@t=4722.html
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Mark_A_W



Joined: 15 Mar 2006
Posts: 3068
Location: Sunny Melbourne Australia

Posted: Thu Oct 04, 2007 12:38 am    Post subject:

IMO the image should be 3-4mm from the edge of the raster. This is probably closer than Doug would go Smile

This is totally source dependant. You cannot adjust this in the projector. You adjust this by playing with the porch pixels in the source. Unless you have a decent scaler or a HTPC, you cannot adjust this.
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Dgeorge



Joined: 17 Aug 2007
Posts: 30


Posted: Thu Oct 04, 2007 3:01 pm    Post subject:

Doug: Yes I did but it only mentions the rasters relation to the tube face. I dont think it says anything about how close the image should be to the edge of the raster.

Mark: I am using a laptop as a source. Right now, the image fills the raster vertically but not horizontally. Since the raster has at least 1/2" at the top/bottom, is there any danger running the image to the top/bottom of the raster?

Thanks guys
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Mark_A_W



Joined: 15 Mar 2006
Posts: 3068
Location: Sunny Melbourne Australia

Posted: Thu Oct 04, 2007 9:13 pm    Post subject:

Top/Bottom or Left/Right...I'm lost..
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whats6x7



Joined: 04 Oct 2006
Posts: 5924


Posted: Thu Oct 04, 2007 9:23 pm    Post subject:

You can make the image larger or smaller with the remote. I believe what he is asking is how large to make the actual video image inside the raster. We all know you can't have the raster off the tube face but he wants to know how close you can have the projected image inside the raster.

As far as I know, it doesn't matter. Play with it enough and you'll end up with half the image on one side and the other half rolled onto the other side (same goes for top/bottom). You can't watch it like that but I don't believe it will hurt the tube at all. I set it up like Mark said just to have a little wiggle room.

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Dgeorge



Joined: 17 Aug 2007
Posts: 30


Posted: Fri Oct 05, 2007 1:46 am    Post subject:

whats6x7: Thats exactly what I was asking. Sorry if I wasnt clear. I thought it doesnt matter but wanted to make sure.


David
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Mark_A_W



Joined: 15 Mar 2006
Posts: 3068
Location: Sunny Melbourne Australia

Posted: Fri Oct 05, 2007 2:13 am    Post subject:

I already answered - about 3-4mm for image edge to raster edge. Do it using the porches. You need to use Powerstrip (ATI video) or Nvidia Custom res controls.

You may find you need to keep the LH edge further away to avoid the kink in the raster due to beam settling.
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Dgeorge



Joined: 17 Aug 2007
Posts: 30


Posted: Sun Oct 07, 2007 1:48 am    Post subject:

OK, I left a bit of a margin at the top/bottom just to be safe.

Mark: Whats that about the kink in the raster? I am setting up my geometry and everything is lined up except for the upper right of the screen where the cross hatch dips on the red (green is straight), Is that due to the kink you mentioned?

David
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KennyG



Joined: 10 Feb 2007
Posts: 254


Posted: Sun Oct 07, 2007 2:04 am    Post subject:

No, if you were having retrace problems it would show up in all colors, not just red.
The red dip you have in one corner is not abnormal...I don't think your XG75 has the line distortion adjustments to remove problems in the corners...however if both corners have this problem, then your pincushion might help here...if not, it's going to take point work...which should only be done as the last resort.
I usually find that one red corner, and one blue corner need point work.
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Mark_A_W



Joined: 15 Mar 2006
Posts: 3068
Location: Sunny Melbourne Australia

Posted: Sun Oct 07, 2007 12:19 pm    Post subject:

Typically it's the Left Side that shows beam settling kinks, so yours sounds like the wrong side.

But in my experience the red will kink the most on a NEC, must be something that gets amplified by keystone. At least with ceiling mount anyway.
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Dgeorge



Joined: 17 Aug 2007
Posts: 30


Posted: Sun Oct 07, 2007 3:36 pm    Post subject:

Mine is front floor mounted (for now) Wink

Yeah, looks like it was just a geometry issue as I was pretty much able to get the convergence bang on without any point convergence.

I do have a question about static convergence. Following Guy Kuo's guide, I centered the raster on each tube and centered the image in the raster. Then I aimed the guns by projecting a field and centering the edges of the field (rather than centering a cross-hair). This leaves the center of the red and blue images slightly off center from green.

I was then able to get the geometry of each gun pretty bang on but I had to use some static convergence to get the cross hatch's overlapping.

I know you want to do little or no point convergence but what about static convergence? Does using static convergence move the rasters or image?

David
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Mark_A_W



Joined: 15 Mar 2006
Posts: 3068
Location: Sunny Melbourne Australia

Posted: Sun Oct 07, 2007 9:47 pm    Post subject:

You need to use Raster Centering instead of Static. Static should be below about 10.

To get into full blown Raster Centering, you need to enter Service mode. To enter service mode you need to have a User Passcode set, but then you use the service passcode of 3151. You MUST have a user passcode set, or it won't work, it's a safety lockout.


Then press CRTL + Position to get Raster Centering or use the service menu.
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Dgeorge



Joined: 17 Aug 2007
Posts: 30


Posted: Tue Oct 09, 2007 2:31 am    Post subject:

Mark,

I did center the rasters with those controls, per Guy Kuos guide. In Guys guide, he actually says that by centering using the edges of the image instead of the center of a cross hair, you will get better use of the phosphor but that the red and blue guns will end up being slightly left/right of center. Unfortunatly, his guide doesnt cover convergence so he doesnt mention how to converge the red and blue with them off center.
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Mark_A_W



Joined: 15 Mar 2006
Posts: 3068
Location: Sunny Melbourne Australia

Posted: Tue Oct 09, 2007 3:05 am    Post subject:

Use Raster Centering to line up the centres now that the Toe in is done.
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