[Jay Wilson]

New thread. Mike I know you're gonna answer this one, so...


First let me say that my ECP has never looked as good as it does now. Funny how having the convergence and deflection yoke aligned would do that If it weren't for Cary and I bouncing ideas around and Mike seemingly always coming to our rescue, I think I'd have gone nuts (I know...short trip) by now. Thank you Mike and Cary!


SO...the last thing I would like better is the keystone. I have it 90% there and want to know if I can do better. I'd like to get ot better WITHOUT using green convergence. To this point, everything else is dead on with no green conv. Alternating between pincusion and keystone...The bottom corners of the pix are about 1" wider than the top. My pin and key adjustments are maxed. I'd like to think that there would be mechanical adjsutments that would allow me to have ot this close and have my electronics controls more at a mid point. In other words, the goemetry I have now, with pin and key at 5.


Mike, I am about to peruse the service manual, but so far you have always had a better answer. Any thoughts on this? Any tips or tricks? Or even another way to do it that you've learned is better?


Thanks!

 

[M NEWMAN]

MAXED??!! What the hell are you doing, Jay? Shooting that image from the moon?! Seriously, the point of the chassis of the PJ where the plastic, lower cover meets the metal front panel is where the top of a 4:3 screen should hit if you draw a line straight back to the PJ. You won't get near max if you do this. Remember that this PJ was designed with conference rm, drop tile ceilings in mind, with a screen at or near the top of the wall. Therefore, if you have the PJ too high, you'll really have to get into those adjustments. Swing it a little lower and you won't. An example: if you're using an 80" wide 16:9 screen, you must calculate for a phantom 60" tall screen (equal to the 4:3 aspect ratio),subtract the difference of your screen height, then divide by 2, and add the result to the top of your screen to get to where that PJ point I mentioned earlier should intersect. That make sense? If not, too bad, 'cause even I'm confused now...

 

[stefuel]

To give you an idea about what Mike is trying to say, that point that Mike mentioned on My ECP is about 6 inches lower than he suggests and my keystone is at 6.5. If your maxed out and your ceiling mounted than your to high. If your desk mounted than your to low. You only have 15 degrees to play with.


Chip S.

 

[M NEWMAN]

That's right Chip...you actually went with an optimum mounting position (top of PJ at top of screen) which minimizes keystone useage, whereas I told Jay the max that he will want to raise his PJ while still maintaining a reasonable key range. When you get above the point I mentioned, you are now really pushing it.

 

[Jay Wilson]

OK, My pj is lower than the top of my screen...just for that reason. There is no way it is too high. I didn't want to use keystone if possible. The top of my green lens is about 6 inches below the top of my screen. I've got a cathedral ceiiling, where the pj is mounted in the center at the high point which is 9'. The screen wall is shorter, about 7'. Therefore I made sure that my pj hung close ( a little lower) than the top edge. Just the "thickness" of the pj makes it hang this low. I've got the Ehome ceiling mount, a 3" pipe, then the pj and this is where is falls.


If I understand you right, I've got a 92" wide screen. Which means I would have to "imagine" I have a 69" high screen. My screen height is 52", meaning I am mounted 14.5" too low? (69(4:3 height)-52(16:9 height)/2+6(current drop) =14.5). I didn't think you could get too low (within reason). I thought (at least with today's pjs) that center screen would be best. I can't raise it more than 3 inches, and because of the cathedral ceiling, I'm not even sure I can do that.


I did however get out the manual and read about zeroing out the mechanical adjustments (yes Mike, the ones you told me don't worry about) and I was able to zero it in a bit better and now keystone is at 6. See Mike, I wasn't shooting from the moon...you crystal ball was slow again You lost that instantaneous diagnosis ability again


Thanks for your help guys! I'll bring the digital camera home tomorrow and take a pix and you can see what I mean.

 

[M NEWMAN]

Wow, it looks like my Crystal ball is seriously out of alignment. I think its making me see zig-zag lines at the moment....What was so out of whack that you were at max on keystone when positioned that low?!!! I can't imagine you having to even "breathe" on the keystone when your PJ is practically "dragging" on the ground, like that....

 

[Jay Wilson]

Well Mike, even your crystal ball is allowed to be out of alignment every now and then. Even though I give you a hard time, that crystal ball has got my pj where it is now, so, it's just a ribbing.


Anyway, I got into the manual, and adjusted for keystone offset and keystone amplitude:


Offset:

scope at row B, pin 14...Press KEY...press up or down until 0 (center of display bar).


Adjust R61 until 0 volts on scope.


Amplitude:

Connect source, set h Rate at 15.7kHz and V at 45 Hz.


Press KEY, press up for max keystone.


Adjust R61 until a)distortion or jitter appears, or b) image sides appear straight when the pj angle is 15 degrees.


After doing this I had to back off on keystone with my standard signal (1280 x 720 @ 72Hz). It worked!