CurtPalme.com Home Theater Forum

JustGreg · Joined: 07 Mar 2006 Posts: 3098 Location: Kenosha, WI

After years of never being quite satisfied that I'd gotten the best physical screen to pj configuration using multiple methods I'm interested in hearing how others have done it/are doing it.

My 8500 just got re-hung after some room and pj work and I'm searching for the 'Ahhhh' factor this time around instead of lingering doubts as with past endeavors. The last time I hung it I used the centers of the lenses to the center and middle edges of the screen. The green tube provided the pj to screen centering. The blue and red to opposing screen middles provided swivel zeroing. It seemed logical at the time as opposed to using walls and the like as baselines. I know there has GOT to be a better, or at least more reliable method.

So, let the world know how you mount a pj. (OK Curt...there's an opening for ya to work with! Laughing

)

whats6x7 · Joined: 04 Oct 2006 Posts: 5924

A -----------Screen--------------B

------------- C--------D
------------- ********
------------- ******** <- Projector
--------------********
--------------E******F

Length A to D should equal B to C and A to F should equal B to E.

dturco · Posted: Sat Sep 12, 2009 2:01 pm Post subject:

Ok Here are 2 ways to do this.

1] Take top covers off use the 2 little screws that hold the big top cover on [which are on the bar that holds the tube pivot bolts] if the measurements are equal to the screen, you are squared to the screen. Smile

2] Use the bolt holes for the feet bolts at the outer edges of the chassis. Measure each one to the screen, if they are equal then you are squared to the screen. Shocked

Or try using the diagonal to each side front and back and tube face to the center of the screen and then reverse all measurements to cross control what you just measured or .... use the K.I.S.S. method above. Thumbs Up

perisoft · Joined: 29 Aug 2007 Posts: 2920 Location: Ithaca, NY

Loosen the mounting bolts and hit it with a hammer until the image is centered.

Wink

dturco · Posted: Sat Sep 12, 2009 2:10 pm Post subject:

ecrabb · Posted: Sat Sep 12, 2009 2:19 pm Post subject:

Hammer... The one tool that does it all. Wink

There are lots of threads on nailing down physical setup. Here are a couple of threads with my favorite method detailed...

https://www.curtpalme.com/forum_archived/viewtopic.php@t=12911.html

http://www.curtpalme.com/forum/viewtopic.php?p=79360

https://www.curtpalme.com/forum_archived/viewtopic.php@t=12056.html

SC

JustGreg · Joined: 07 Mar 2006 Posts: 3098 Location: Kenosha, WI

I knew I was bound to get a couple of good guffaws out of this.

6X7..you get an A for patience because I KNOW you had to play with the placement of each character to make it display correctly.
And...except for measurements to the rear of the pj that's exactly how I've been doing it.

And the hammer...well, I already used that once getting the ^%$*#@! bright spot into the middle of the green blob. Twisted Evil

What a fight that was! Shocked

dturco, I never thought to use those screws as they aren't on the extreme edges of the pj...that and one of them is holding the HV splitter temporarily whilst I dial everything in. Gotta tell ya, either I'll lose more hair on the top of my noggin or grow more what with all the static zaps my chrome dome has taken working under the beast. Laughing

And as always SC, a great source for not just one resolution to a problem but multiples; which ultimately leads the poster to a greater understanding of his initial question. Thumbs Up

Just home from work so off to the dungeon I go to give everyone's recipe a shot.

Thanks all! Thumbs Up

**AnalogRocks** · Posted: Sun Sep 13, 2009 5:12 am Post subject:

don't forget take 2 Aspirin and call us in the morning. Laughing

JustGreg · Joined: 07 Mar 2006 Posts: 3098 Location: Kenosha, WI

OK here's one for you guys...I'm using the image centering/alignment pattern that I picked up here over the years (apologies to the OP for forgetting who you are) except instead of just using it as printed on 8.5x11 paper I cut it out of a manilla folder to make it more robust.

Anyway, I used it to center the crosshatch pattern after a full init and the internal pattern just doesn't 'visually' appear to be dead center. I'm of course centering with the focus coil.

I've measured the centerline of the alignment pattern and it's dead center. I've taken the plate off a spare tube to get up close to the tube face and verified the alignment tool is dead on. BUT....looking at the finished result all three tubes show the internal pattern too far left with a disproportionate margin of unused tube face to the right side. It's not a bow or keystone abberation either.
I want to maximize usage but if I do the patterns run off the left side of the tube face (using the alignment tool). If I reduce size to prevent that, I now have a big chunk of unused tube face on the right.
GAAAAAH!! I'm totally blown away by the illogical nature of this. I shouldn't be seeing what I'm seeing. I know I'm counting the grid lines correctly....hell, we're not even talking double digits here!

Would visually centering (horizontally) the pattern null the benefits of BB's Magnetics 101 guide? (Or should I chuck it all and seek professional medical help). Laughing

**AnalogRocks** · Posted: Sun Sep 13, 2009 5:32 am Post subject:

Have you centered all your electronic settings? ( dumb question? )

JustGreg · Joined: 07 Mar 2006 Posts: 3098 Location: Kenosha, WI

Yup...everything nulled. I 'think' I know what it is. It has to be C and S linearity that's causing what I'm seeing. Short of pulling the lenses and measuring every segment I'm going to go with that for now and see if the parts n' pieces of the internal pattern that are wrapping around the edges pull in after I get a rough geometry set up.
Enough for tonight tho. Tomorrow's (today) my only day off and I don't want to sleep it away.
Thanks for the input guys. More questions to follow (forewarned and all that). Laughing

stefuel · Posted: Sun Sep 13, 2009 10:48 am Post subject:

You say you have a tool to center the crosshatch? If you can center a "center cross" then that's all you need for lens aiming. Whatever is going on with your linearity is a electrical problem and shouldn't be considered or confused with mechanical aiming. Using a piece of 3M easy release tape, mark the center of the screen. Carefully mark on the tape the dead center position by drawing a X on the screen. Now point that perfectly centered green center cross on that mark and lock the projector down. If the projectors mounting position is correct, your green tube is perfectly aimed. You will find that if you use the same method for centering the blue and red center cross that the height will be off when you toe them in to overlap the green. This is normal and it's OK to adjust that out electrically.

dturco · Posted: Sun Sep 13, 2009 1:31 pm Post subject:

I will admit I am not the most accomplished setter-upper here, But if you are following Bill Blue's guide the way it's written and use an internal pattern the whole time, I have found issues like you are describing when I put the 1080p signal to the Marquee after set up.

Use your source to do the set up because you have some idea where you need to be from prior set-ups use that knowledge to your advantage.

I know that GOZER needs to be on short retrace because of a shift issue with the Moome card so I always start with that short retrace 1080p signal applied go straight to 90h 35v [because this is what fills my screen,yours will be different] and then do the setup as Bill Blue's guide instructs.

I have found another way mentioned by TSE to start with

http://curtpalme.com/forum/viewtopic.php?t=17325

I am looking for another post by TSE for super easy way to find where to lock down the tubs/lenses

But basically he said to apply a full white field and match the edges of the colors by using your remote color 1,color 2, color 3, I am skipping a lot because you have done this before so.......