CurtPalme.com Home Theater Forum

[Elaine Benes]

Ok, look at this picture. The circled area NEVER MOVES when you adjust Key/Pin. I've put arrows on the picture showing how Key adjusts the ends of the grid, when you get an even amount of red at both ends, but only on one side(parallel to the grid line), then you just adjust it, usually down, to the green with the PinCushion adjustment...



Simply start with the top, complete it, then move around the outside in a clockwise pattern doing the same sequence in the four zones which ring the grid. Focus again ONLY where the adjustment is effected...this time basically only corners...

When this is ALL DONE, you *may* see a need to slightly re-visit Amplitude/Linearity, but that is not always the case...

[Satanier]

Wow!!! I'm finally understanding it all now!!! You have been so much help I can't thank you enough, here's my convergence as of right now::




One thing I notice is the left middle the red is shifted slightly down, and the top middle slightly left.....


*****************************

It should be noted that the left side of my image wont come into proper focus, via electronic or physical adjustments, but thats a whole different issue.


I dont notice it in movies, only windows desktop.


This is incredible, I think the red is fully converged!!!


Should I have blue focus tracking on or off when I move onto the blue?


And after all this should I turn AKB on?



Thank you so much for all the help!!!

[Elaine Benes]

You just need a tiny bit more tweaking on horizontal axis of Tilt/Skew/Bow to get that dialed in I'd bet...

Notice you're not using ANY point convergence ??

You can turn AKB on for a while, then shut it off, you don't need to run it all the time,just run it for a few minutes every time you turn it on and your color balance will track pretty accurately over time.

Focus, yes, that is a whole other issue, and as I mentioned earlier, you really should do ALL your focus before convergence as your convergence will change when you do your focus.

But I wanted you to get through one convergence so you could see that it really isn't all that bad when done in the correct order, and the result is always good when done like this. So you're now equipped to own any NEC, and set it up repeatedly for any number of inputs and all kinds of tweaking...

Let me know when you're ready to do focus, we'll go through that too...

[Satanier]

I went ahead and did the blue, here'es my final result, its off a bit in some places, but man I had lost all hope and you explained it so well no I understand how to do it!!!!


I can't believe it worked!!! It's sooo easy now that I understand where to look and what each control does



Heres my final result, maybe theres a couple tips for nudging the areas that are slightly off into perfect convergence


Wow!!! thank you!!!! I owe you one










PS:: I did the focus roughly before the converge, the left and right of the green and the blue to a lesser degree just WONT focus at any range, so I think something is wrong or theres a pot that needs adjusting.

[Elaine Benes]

Now that you've got the tools, figuring out what to do to correct the misconvergence is a simple deductive process...

Your blue just looks like you rushed through it a bit, go through it from the start again, you can use some Tilt/Skew/Bow on the blue in the veritcal plane, easily seen, same with red, which will affect your Key/Pin to a slight degree. Blue looks like it can use some Amp/Lin attention too, as there's too much on the right, not enough on the left...

Just some more tweaking. Enjoy it for a while, run some video through it for a while, then come back and run through the convergence IN ORDER again. The amounts of adjustment will be much smaller this time through, of course, you'll end up getting it closer and closer, just remember to do it in the same order so you don't end up fighting one adjustment with another, they should complement one another, not fight against one another...

Just as a start on focus. It begins with a tape measure. You check, and double check that your projector is EXACTLY perpendicular and centered to your screen, then you double check the manual to be SURE you have the scheimpfluge tabs set properly for your screen size AND SHAPE....
If that all checks out, and your projector is set perfectly(within 1/16") in relation to your screen, then you can go about doing the electronic focus.

That starts on green.

First I'd null all green electronic ASTIG, just use the Cancel/Yes method. When you've nulled the electronic astig, do the same for electronic focus.

Go back to electronic ASTIG, get the center perfectly round, or as round as possible, do this at high contrast so you can see the blobs easily, go through every zone for electronic astig, get them all round, exit and SAVE it.

Go to Focus, start in the middle with green use the Focus pattern in the internal menu, OR a good "Focus" pattern from your source. Personally, I prefer an external sourced "H" pattern, adjust the focus in all zones optimally.

If you STILL can't get proper focus after attempting this in this order, THEN its time to investigate further. There are "Focus Balance" controls and "Focus Tracking" adjustments in the menu's that might be mis-adjusted...

[Satanier]

Thank you SO much for helping me through that convergence nightmare, I now understand how all of those settings work, and where to look when adjusting and how to use them in pairs. My convergence is now decent enough and I can tweak it from here with the info you have given me.

As for the focus:
Yes I've adjusted the astig as close as I could get it, using the high contrast method, then I did the focus, but its way off on the left and right for the green and for the blue to a lesser extent. The red looks totally fine. I think something else is wrong.

I also have a geometry issue that I have no idea how I would fix:
You can see in the below image what it looks like, I do notice this in movies when I see round objects, and other times when things are positioned in the most distorted zones...

[Elaine Benes]

That picture illustrates why I use an image from the actual source to do my Alignment after convergence...

Just leave that up and go to your Alignment menu, choose Linearity to start, adjust it a bit in the vertical plane with all three colors on, see if you can get the circles closer to round. Amplitude in Alignment will have to be adjusted somewhat as well, and perhaps Linear-Bal too, but leave that till the end. Red and Blue will track fairly well with Green when you do your Alignment adjustments, but you'll also likely have to run through Convergence again to touch it up...

As for focus, I assume you know there are two focus rings on each lens and I assume you've used them to focus the green all across the screen evenly(optical focus...) ?? Also, I assume you've seen there are "Edge Separate" as well as "Edge All" and you're in "Edge Separate" mode for edge focus adjustment ?

[Satanier]

[Elaine Benes]

The circles may appear to be squashed in different ways, but that doesn't mean that correcting your geometry won't straighten them out, or mostly straighten them out...

Remember, all controls have an effect not ONLY on the area they DIRECTLY affect, but on other parts of the screen INDIRECTLY. As well, adjustments have to come in the correct ORDER to have the desired effect....
The rule of thumb is to apply corrections in the order they appear on the list, starting from 1. If you don't need to apply a certain correction, then don't, the less correction used the better...
You didn't null your entire Alignment before starting, I didn't want to scare you any more than you were, but nulling Alignment would have been a good idea. You are likely working against the old setup somewhat now which would be a convenient explanation for the squashed circles. You have both lots of RANGE in your controls and lots of CONTROLS available to you to adjust the geometric anomalies you see...
Try what I suggested, keep that image on the screen, keep all three colors turned on, but go to the Alignment menu and try working with Linearity an Linear-Bal to see if you can get the circles all round all over the screen. I suspect you'll need to reduce overall Amplitude somewhat too in the vertical plane to achieve proper shaped circles, but work the various Linearity controls first to see if you can get them all even at least in relation to your vertical center so when/if you need to adjust Amplitude, you can do so and maintain the proper shaped circles...

[Satanier]

[Elaine Benes]

Is your focus equally poor when you look into the lens directly at the pattern on the tubeface ? This is how to tell if its electronic or optical in nature... If you vary your center focus electronically, do the edges get better/worse or do they stay the same ??

It's possible someone adjusted the baseline electronic focus pot without first nulling all the electronic focus controls...Possible, but no way to tell without a few simple tests...

When you want to give your projector a break, just run some video through it, this XG75 I put on the coffee table has been running constantly since about 11am this morning with no ill effects whatsoever, running video doesn't do them any harm whatsoever...You don't want to be doing hours and hours of setup work straight without taking some breaks to run video...

You asked earlier about the green having an "after" image on it, that is normal. The "persistence" or the amount of time the phosphor continues to react when the electron stimulus has been removed is longer on green than red and blue. One can get a "fast phosphor" tube, but they are not ideally suited for video display, they are more intended for computer graphics where the green persistence is somewhat more likely to be visible. With normal video use, we expect the green persistence....

Don't worry about how much of your tubeface you're using.... you'd need to run it for AT LEAST hundreds of hours at really high contrast to have it negatively impact your tubefaces.... Personally, I think one should use close to the factory mount position, which results in a fairly small raster, but feel free to expand your image to within about 10mm of the tube sides. The point where you judge this is the point of the image that is nearest the tube side. It will be a point because of the trapezoid shape of the image area caused by the mounting angle. If you want to eliminate this, you have to mount your projector at a zero projection angle, ie. with the rear part raised so you shoot directly to the center of the screen. If you mount like this, the whole side of the image will be parallel with the tube sides and you can use considerably more tube area even if you don't have it any closer to the tube sides...

[Satanier]

Well here is the geometry after tweaking the alignment, its the best I could get it and a couple of the controls are near 100, I hope that's ok?

I still have an issue with the upper left, its the blurriest of all and the image distorts there. 2.35:1 movie really shows it, the whole frame tapers on the left side and is shorter on that side than the right, I put a window on my desktop in that corner as well as in a normal place on my screen to try to show the effect that corner is having....

The convergence looks off in these pictures but it doesn't look nearly that bad in person, anyway:

The geometry after tweaking:::





The corner problem:::(faint vertical white lines on left /// far right problem is also visible slightly)

The yellow band is from the camera on 2nd pic

Window in upper left corner:



Window near center:

[Elaine Benes]

It's never good to have any controls nearing 100%...that being said, there are a few controls which are typically fairly high in the Alignment menu. KeyStone for instance is usually around 70, in one plane, and 30 in the other. Its like this on all make and model of projector too because they all have similar projection angles...

Did you try to adjust the controls in the order they appeared in the menu ?? Did you keep in mind WHERE on the grid the controls had the greatest effect ? Just like convergence controls pretty much ONLY affect certain areas, so too do Alignment controls only affect certain areas...

Some controls have a more global effect in Alignment than they do in Convergence though. Like KeyStone and PinCushion. In Alignment, they affect the outermost edges as a whole instead of just each "zone" like in convergence...

This is where someone who is pickier about Alignment will hopefully jump in, I don't care all that much about getting perfect geometry, "good enough" is pretty much all I strive for. There's sometimes a lot of back and forth between the various "balance" controls to get things just so don't be afraid to keep tweaking away at it.

[Satanier]

[Elaine Benes]

Amplitude is fine being a high number, that's just image size, but Linearity is troubling. Are you sure its not more of a Linear-Bal issue ?

[Satanier]

[Satanier]

I did more tweaking of my convergence as it had changed when I adjusted alignment.


Here is where I'm at:




And here is a high resolution image, it looks quite good in person, but notice the tapering to the left side...
(Bottom right and bottom left aren't the lines im describing, those are physical wrinkles in my screen.)






Unresolved issues:

1. Slight tapering on left side ( I can live with it)

2. Bad focus on right and left side with green and blue tubes, certain corners for these tubes have focus issues as well.

3. Something funky relating to both the focus and the tapering in the upper left corner.

4. When all white is displayed, its not really even all the way from left to right in shade of white, plus there is these vertical bands near the left and right sides


Overall though, I think I'm doing pretty well!!!


One question too, is there anything wrong with shutting off the front power switch on the unit when I'm not using it? This is after shutting it down using the off button on the remote, of course.

[Elaine Benes]

It's very difficult to judge geometry issues from photographs because of barrel distortion caused by the camera....

Of course its ok to shut the projector down using the front switch, many users do that, some feel it affords them a measure of protection from power surges and such.

If the left side is narrower than the right in the horizontal plane, can you even it out with horizontal KeyStone Alignment adjustment ??

For your green focus...null ALL electronic focus controls, take the top of the projector off, you'll see three white pots marked FOCUS. Carefully adjust the FOCUS G potentiometer until the middle of the focus pattern on the green is perfectly focused. Now go back into your electronic controls and see if you can better focus all of the zones you have access to through software...

IF that works, do the same for blue, make sure B-Focus Tracking is set to OFF in the Setting Mode menu found under Option before you do that though, as B-Focus Tracking is the control which evenly defocuses blue when set to "ON" for better color temperature tracking.

[Satanier]

[dropzone7]

Holy crap! You guys pulled an all-nighter with this I see.