CurtPalme.com Home Theater Forum

jeffslife · Joined: 17 Apr 2010 Posts: 4190 Location: ohio usa

Thanks you guys,
That explains SO much
So what is the angle I am looking for when I
tilt my PJ the other direction?
2 Degrees? more...
thanks

VideoGrabber · Joined: 09 Apr 2006 Posts: 933 Location: Michigan

dturco wrote:
> So yes if your G-70 is firing towards the ceiling {back lower then front} you keystone will be harder to deal with. <

Would you like to reconsider that? Smile

The lenses are already mounted at an angle to the chassis, that the PJ was adjusted for at the factory. If you tilt the back down a full 15-deg, the lenses won't be "firing towards the ceiling", they'll be horizontal to the ground and perpendicular to the screen. Keystone will then be 0, not "harder to deal with".

jeffslife · Joined: 17 Apr 2010 Posts: 4190 Location: ohio usa

OK, Now you guys are losing me again.

dturco · Posted: Fri Nov 05, 2010 1:38 am Post subject:

jeffslife · Joined: 17 Apr 2010 Posts: 4190 Location: ohio usa

I saw the picture in the manual and the pj appeared to be mounted on the ceiling level.
I thought I was just not understanding it.
So is there an optimal angle I should shoot for?

dturco · Posted: Fri Nov 05, 2010 1:40 am Post subject:

jeffslife · Joined: 17 Apr 2010 Posts: 4190 Location: ohio usa

This is gonna change EVERYTHING.
How dumb do I gotta be to miss this.
So is there an OPTIMAL angle?
16x9 54 X 96 inch
throw is 130 inches.

jeffslife · Joined: 17 Apr 2010 Posts: 4190 Location: ohio usa

So, just to be sure zero IS my optimal angle?

dturco · Posted: Fri Nov 05, 2010 2:02 am Post subject:

Yes, but look at the above posts. I was wrong and Videograbber was right in all of his posts. Embarassed

jeffslife · Joined: 17 Apr 2010 Posts: 4190 Location: ohio usa

DTURCO,
thanks for straightening that out for me. 7 degrees is cool,alright.

Thank you too VIDEOGRABBER I appreciate it.

jeffslife · Joined: 17 Apr 2010 Posts: 4190 Location: ohio usa

One last question, Is zero BETTER than 7 degrees or is it not significant?

dturco · Posted: Fri Nov 05, 2010 2:19 am Post subject:

Elaine Benes · Joined: 25 Apr 2006 Posts: 1416

Is this your first experience with the Sony/NEC setup philosophy ?

If it is, relax, run through it a few more times, and take note how each adjustment affects the WHOLE SCREEN.

What you also have to keep in mind is that you won't be able to see the *needed* adjustment until you've completed some adjustments. For instance, you can't see if you need to do BOW adjustment until AFTER you've done Tilt/Skew. Now I'm using NEC terminology, but it applies to Sony fairly closely.

Also, when doing convergence, keystone/pincushion virtually ONLY apply to the outer regions of each of the horizontal and vertical bands. Also, after you do keystone/pincushion, it often points out the need to revisit Amplitude/Linearity...

And personally, I try to stay away from any of the "balance" settings, usually they only exacerbate the lack of ability to tightly converge...

Spend much, much more time on the wave form convergence so you don't have to do virtually any zone convergence.

And don't converge for too long at a time, take breaks and watch video for periods.

jeffslife · Joined: 17 Apr 2010 Posts: 4190 Location: ohio usa

Thanks for the advice. This is my fourth set up of my g70
The PQ gets better every time I REDO it.
I am starting to figure it out (a little)
It amazes me how much one little move changes EVERYTHING
I am going to go through it AGAIN tomorrow
using all the tips I have got this week,I am sure it if not easier
will be less time consuming as I am becoming more familiar with how the controls work
And NOW that I know how MUCH one affects the others.
My main goal tomorrow is to try to use as little ZONE as possible.
Wish me luck, I need it
THANK YOU ALL !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

**AnalogRocks** · Posted: Fri Nov 05, 2010 3:54 am Post subject:

Jeff, my first setup took me around 18 hours, looked terrible and was a blast! Then I got the manual and it all went so much better. Stay with it.

jeffslife · Joined: 17 Apr 2010 Posts: 4190 Location: ohio usa

what is your opinion on using internal test patterns?
I hear it both ways.
I have BD set ups for grayscale and color but not for
convergence or linearity
or any idea how to use an external convergance disc.

VideoGrabber · Joined: 09 Apr 2006 Posts: 933 Location: Michigan

[...got interrupted by a phone call. Wrote this 3 hours ago...]

BTW, having the lenses horizontal, and with keystoning 0 would be the optimal situation, since that gives you the best rez using the minimum bandwidth. Unfortunately, doing so requires placing your PJ lenses right in the middle of the screen, height-wise, which usually is not feasible. The whole reason the lenses are angled down in the first place is because people want to mount the PJ on the ceiling, with the screen lower down on the wall (or flip it, for table-top mounting). And the PJs are designed to handle that perfectly well. But that's why you wind up with trapezoidal wear-patterns on your tubes.

To do what you've described, you must have your screen mounted a bit higher than normal, thus requiring less tilt to compensate. The worst case is when the screen is so low that you have to tilt the front of the PJ down even further to hit it, which increases keystoning, and the amount of adjustment needed to compensate for it. The picture will be harder to dial in, the quality will be degraded, and you may even run out of adjustment range entirely. From what you've said, you don't have to worry about that.

jeffslife · Joined: 17 Apr 2010 Posts: 4190 Location: ohio usa

I see, now my tubes have 1500 hours on them
if I can set the angle to zero(I think I can)
will it change the way the phosphur looks on my screen?
I guess what I am asking is will it put my picture
into unused phosphur and show up on my screen?

VideoGrabber · Joined: 09 Apr 2006 Posts: 933 Location: Michigan

Jeff,
> if I can set the angle to zero(I think I can) will it change the way the phosphor looks on my screen? <

Which angle? The angle of your PJ frame, deviating from horizontal? Or the angle of the lenses shooting onto the screen.

If you meant the former (positioning the screen or PJ so you can level out your PJ), then that will increase the keystoning a bit (relative to what you have right now). That will squeeze the small side of the trapezoid a bit more, the new wear will be within the old, and thus not visible.

If you meant the later, that will expand the trapezoid to a rectangle, with portions outside the previously used region. If you can currently see a wear pattern, those areas will then be brighter, as you suspected.

Elaine Benes · Joined: 25 Apr 2006 Posts: 1416

On an NEC, pretty much never bother with the internal patterns, as the resulting set up will be "off" when you resume with material from your source. However, Marquee internal patterns are very good, usually an exact match with the external source. Sony's are generally very close to the external source, but its still a good idea to use source patterns whenever feasible because then you're setting up what you're ACTUALLY going to be using, it eliminates one more variation when doing a setup.