CurtPalme.com Home Theater Forum

[ccaddaddy]

where do i find one?

[gjaky]

The meaning of the term ACAT changed during the years. the original ACAT was a camera based auto convergence system, probably the least useful, and most problematic amongst of all CRT auto convergence system, don't bother with that. Then with the last series of the XG NEC introduced the interpolated convergence setup tool, sometimes referred as MCAT, but appears as ACAT in the menu, this came with the XG 852 and 1352 projectors only, there is nothing you can do to add this feature to your older XG (...0, ...1)

[CasetheCorvetteman]

You dont need it, the convergence on an XG is so damn easy to get perfect there is no point in complicating it.

If youve got a 1352 or 852 the ACAT is under the POINT menu, and does work reasonably well. Its still quicker and easier to just do it properly.

I connected and set up 6 sources on an 852 a few nights ago in about 2 hours, all from mid point.

At the end of the day, if you dont set PHASE correctly before you do anything else, youll struggle to get it right no matter what you do.

[ccaddaddy]

i dont understand phase.lol

[gjaky]

Before making any adjustments on a new (to you) machine it's worth to take a look at the phase adjustment, Phase sets the convergence reference point to the screen, if it is way off it's like you set something in the center and the edge is moving

[CasetheCorvetteman]

What Gabór said. I can elaborate further later on if you like, but make no mistake, it all starts with PHASE on an NEC.

[ccaddaddy]

yes please elaborate.

[CasetheCorvetteman]

When you start, you connect your source ( i use 240p for the first entry, i recomend you use to lowest you can, preferably progressive scan ), turn everything on, itll display a terrible out of alignment image, and you begin with PHASE, located at the bottom of the CONVERGENCE menu.

By this time, you have allready been to REF ADJUST and centered rasters, pointed tubes, done mechanical astig, done electronic astig, done focus, and everything is pointing dead center.

In the PHASE menu, the crosshatch grid will display, turn off red and blue, you will see a hump in the middle horizontal line of the green. You want that hump as close to dead center as you can. You also want the lines to be as close to straight as you can, or at least have the same curve radius from one side to the other. No bent up ends. You want the vertical center line to line up with the peak of the hump. When all this is done, exit and save.

Next up, crosshatch, set keystone and pin cushion close, turn off test pattern and using your source image, set amplitude and center the image using the image shift settings. Just get it all very close.

Now do blue and red linearity, especially horizontal ( vertical lines ) because after you do this, you will need to re-center your red and blue rasters ( i do this with the source image, which you have allready centered perfectly on the green ), then re-aim red and blue tubes. Use the cross hair for this, same as before. You do this because the center of the red and blue image is NOT the center of the tube face.

Next up, youve aimed the tubes, re-checked lens focus, called out to the wife for another beer, and mechanically aligned tilt/skew. Now you will do electronic tilt/skew, bow and center line distortion, starting with green, then merging red and blue to suit. Once done, you will have 4 same size boxes on your screen, separated by your perfect white cross hair.

Your green can now be aligned to the edges, this means keystone, pincushion, amplitude, key, pin and linear balance, linearity, line distortion, FINE RGB POINT, etc, til the image is right on the edge on the screen all the way around. You can start this off with the cross hatch, but finish it off with the green source image. Itll all be perfect, and its now time to start red and blue. Use of RGB POINT is your last resort, the others should get you pretty close to perfect, play around with each one and see what they all do.

You will have allready got the cross hair aligned for red and blue. It matters not which you do first on an NEC. Use all the settings listed above to get the red and blue ( one at a time, leave the other turned off ) perfectly aligned over the green. It all works nearly the same as the green adjustments, making it so f***en easy and quick to get it perfect it not even funny. Finish off with FINE POINT.

Save all this, then to default area as well.

I never use coarse POINT. Buy a Barco if you want to do this. Medium also rarely touch, its hardly needed in almost any case.


You could use an external text pattern to do the convergence, but in my experience its not required on an NEC, provided you set PHASE correctly at the start.

Gabór may wish to expand on this, but its all pretty simple.

[gjaky]

[jask]

If you want further information read post #8: http://www.avsforum.com/t/98042/yikes-holy-focus-guy-kuo

and then re read it a few times.... it is not as hard as it sounds.

[CasetheCorvetteman]

[jask]

I used the binoculars a few times but found that a vidocam or dslr on a tripod made it a lot easier to visit w while adjusting.

Edit: autocorrupt

[CasetheCorvetteman]

I have read all that one before yes. I use the binoculars in the corner focus as well as centers.

[the big E]

[CasetheCorvetteman]

Your 10PG will vary slightly, but not much.

[the big E]

[gjaky]

[CasetheCorvetteman]

No, its another thread for another day.

This is about XG convergence and how perfect it is.

[the big E]

[the big E]