CurtPalme.com Home Theater Forum

[samcguire]

I had previously set up my NEC 6PGXtra using the internal test patterns. The raster and image is centered on the tube face and phase is dead-on to my screen center. I had noticed in the past that my movies were shifted slightly to the left of center. I downloaded the NEC test pattern generator and the image is shifted about 3 inches to the left ( and obviously off center on the tube face).

Rechecking the measurements on my tube face and using a laser pointer to the screen, raster, image and phase seem correct with the internal test patterns.

Can I get some advice on where to go from here?

Thanks, samcguire

[AnalogRocks]

You need to do your setup with external patterns. Someone with NEC experiance will pipe in an tell you how that's done.

[AnalogRocks]

You need to do your setup with external patterns. Someone with NEC experiance will pipe in an tell you how that's done.

[Tom.W]

Why not just re-adjust the phase using the input signal as a reference ?

[samcguire]

When you enter the phase screen, either through the menu or the button on the remote, it defaults to the internal crosshatch test pattern.

BTW- my signal entry is from a HTPC running PowerStrip.

samcguire

[Tom.W]

Send a PM to Doug .

http://www.curtpalme.com/forum/profile.php?mode=viewprofile&u=71

He should have the answer...

[dbaisey]

The NEC's like others started life as a 4:3 multi-purpose display device for video, data and graphics. These on the most part used vesa standards for the common signal properties. The phase and shift are used for the various corrections that need to be made to work with these standards over a broad range. The test pattern generation is not perfect when using the freq's and formats that we run today or when manipulating lets say powerstrip or phase differences.

When using the projector for mainly HT or single purpose we set up for the specific freq's we do use so it will have some oddities that we work around. Signal timing and how we overcome side ringing and porches of the different signals is mainly done with the active signals you will be using and not the internal test patterns. Its give and take but usually the internal cross-hair will be off when centering for optimum use. You reach a compromise but also depends if you have a point card installed and active where cursor phase needs to align and make corrections at a given spot.

I would suggest using Avia for the test patterns or if you have a processor that will generate real time patterns you can use those like the ones in the Lumagens. Check the source and processor for being at default where no position corrections have been made first. HTPC's and porch settings also needs thought and blanking on the projector backed out of the way with H position set to mid point.

Do the signal entry then phase the signal. Use a cross hatch pattern for this first and looking in the tube face. When you hit phase it will go to the internal phase pattern but hit the test button then the end button and it will go to the active signal pattern but still in the phase function. This might take a few attempts. Make the tilt phase (left and right arrows) adjustment correction. With a point board installed and active align the hump on the vertical line for correct point of correction. Store these settings. Correct linearity at all four sides and store. From there select the cross-hair pattern and see what you have to work with using position and other small corrections in phase. The final phase setting will affect edge focus so this will need some corrections.

When doing other signal entries this will need to be done for each signal line then use position to make corrections for that signal.
H position values will be different in most cases because of freq and each signals porches or properties.

The early PGs dont have the phase control the newer Plus and Extra models have. This should give you a general idea of how things work but once you actually do it a few time you will see more. The electronic astig is global for all signals so correct this once to make optimum then don't change. Doug

[dbaisey]

samcquire,
So.....what did you end up with? Curious what your HTPC output is. Doug

[samcguire]

Doug-

Sorry about not responding earlier, but got tied up in another project (Dang IRS). I am heading into the theater room now to work on it. The PJ is warming up as I write.

Will respond later today or tomorrow. This is my main project for this weekend.


samcguire

[kevin_k]

Doug,
You mentioned global controls. I'm going to redo my set-up. Obviously, I need to work through all the mechanical issues, but what changes with each signal input. ie., What controls are global and what are signal driven.

Thanks again for your help Kevin

[Elaine Benes]

[dbaisey]

Unlike the XGs raster centering the PGs are mostly mechanical so not alot in electronic global that you will run into. Electronic astig is global when telling the projector where the screen is. Also if you move the alignment magnets it will change mechanical astig at the center of the screen, it will also change where the alignment magnets were just set at so you need to go back and forth. Once you get it perfect you can store it to default so the projector knows its not a 100" diag 4:3 screen.

One thing you want to check when doing set up to see if your close. Use a 16:9 DVD first for set up then load a 2:35 movie and check to see if it is centered top to bottom. If not find out why, usually its linearity, linearity balance or position isn't right in the source or projector. If using a SDI source some of these can be a bit off and some may have a SDI offset in the player or processor.

Learning set up and the little things that make it better will take time. Upgrading hardware is always ongoing and not exact on signal properties. You will learn the personality of the projector as you go along. Doug

[KrisRoberts]

I had always used the internal patterns with my Sony projectors, but was frustrated that when I switched back to the input signal it was slightly different.

To fix this I made some that are similar to the internal cross and grid. You can copy them to a memory stick and put them in a PS3, or use the Xbox360/PS3 view pictures (if networked with a PC) or run them from a HTPC. For me, it made doing the adjustments straight forward to have either the cross or grid and the end results are great.

Just in case it helps other people, here are jpegs of the patterns I made:

http://www.vidya.com/G90/test_patterns/1080_Cross_01.jpg
http://www.vidya.com/G90/test_patterns/1080_Grid_01.jpg
(right click and save)

If you view them in your browser or on the pc make sure to change it to 1:1 or else it drops parts of the pattern since the lines are just one pixel thick.

Kris

[samcguire]

Doug-

I attempted using the pattern from my HTPC without success. Following your advice (test-end) I backed out to the external pattern and remained in the phase function, but hitting any of the cursor buttons returned the internal phase pattern. I was never able to phase with the external pattern.

My HTPC is running WinXP with an Nvidia GeForce 7600GS through PowerStrip. I have used the Avia Disk patterns. My goal is the best setup possible with the least use of the electronics for geometry. I had mentioned previously that my raster is centered and the image and phase centering on the screen is almost perfect with the internal signals. I can move the external image to the center of the screen with the Position-H slider (at about 25), but was looking for a way to align the internal and external signals.

Guy Kuo (Holy Focus) stated that "If you have a machine which allows adjustment of internal test pattern timing, it is possible to center the internal test patterns to coincide with the center of actual video signals." Earlier he had said that internally generated test patterns"tend to be off center and not exactly scan locked to match a real signal." Am I correct that if I have to use much H-Position to center the external image after phasing the internal signal to the center of the screen, that the internal pattern is not centered with the actual video (external) signal?

I also tried centering the image with the Nvidia software and PowerStrip instead of Position, but they had insufficient range to move the image to screen center.

Should I just live with using the H-Positioning and move on, or do you have another suggestion?

Also, this NEC 6PGXtra does not have the point board, although I understand that was an option. Would this board allow me to center the two signals? Are they available and could I expect to be able to add the board myself (I build my own computers)? It's a long way to send the PJ back to Curt.

Thanks for your help.

samcguire

[dbaisey]

1) If you hit phase did it ask for a passcode? If yes and you entered 2580 then it should work and does on all the others. Just did it on the test chassis. Correction: This will only work in tilt phase, left right arrows. Top and bottom arrow will take you back to internal. Sorry about that.

2) You use the external.

3) Set H position to 0 to start with.

"Am I correct that if I have to use much H-Position to center the external image after phasing the internal signal to the center of the screen, that the internal pattern is not centered with the actual video (external) signal?"

After tilt phasing yes it may or may not be aligned with the internal. The internal usually is off to the left. What H position value is needed to center the cross hair?

4) Try after doing the above but source should be mid ranged or what ever is with no corrections

5) Dont know. Im not sure what you doing in 2-3-4

6) No, yes, yes dont really need it but its a drop in turn on. If you bought from Curt make sure he knows what your doing if it is under warranty. He may want it done a different way.