Greg is currently modding several of my boards on my 1209/2 and I cannot wait to get them back. I want to make sure I set up everything right when I get my boards back and my biggewst question is lens flapping. I have always had focusing issues away from the center of my picture, mostly in the lower corners. I know I need to adjust the lenses but I am uncertain where to start. Here are the specs on my ceiling mounted set up:

Projector is currently tilted downward at a 10 degree angle (adding 10.5 degrees for lens angles makes the total angle 20.5 degrees). The screen is 102" and the distance from the PJ to the screen is about 136" or a little over 11 feet. Any help on where I should start would be very much appreciated.

20,5 deg projection angle is too much for HQ picture IMO. Even lens program didn't even want to calculate anything, before horizontal freq is dropped to 15 KHz. Max angle for 135 KHz is 10.5 deg...

With 20,5 projection angle you need to adjust lenses 1.1 degree angle compared to tube faces. So lens down edges need to be about 4.5 mm further than top edges.

Is that much tilt even possible in 1209/2?

If it have same lens equipment what my BG1200, there is no real sheimpflug adjustment. Adjustment need to be done between C-elements and lenses using washers, thats why I'm sticking with 10.5 angle...

My media room has a cathedral ceiling boxed off at the top. I have about a 4 ft drop from the ceiling to the PJ. I am using a chief mount that allows for adjusting angle as well as tilt, etc... I never thought the whole angle thing through when I ceiling mounted this monster. I will try the adjustment when I get everything back. Thanks for the input.

how can I set an avatar on this message board? hehe

Is there somewhere I can find the program that calculates lens flapping for the older Barcos?

http://www.cineversum.com/homecinema/en/do...ds/software.htm

Needed Sheimpflug can be seen in text section...

Thanks. I found the download over the weekend and played around a little. It makes since that the vertical adjustment I need would occur lifting the lens from the bottom (nearest the floor) but I am unsure of the horizontal adjustment; however, the adjustment is so small that I think I could probably ignore it.

Hi,

The washers work well. But you have to adjust the center as you are using the washers.

I have sometimes used small rubber grommets and but them in-between the lens and C-elements.

So you can adjust the screw then I get it totally right and measure with a gauge like the ones you use adjusting the values on an engine.

You then find the correct washer with the same thickness or add two tougher.

Like I said it’s kind of a pain however, the positive is that once it’s set its set and you won’t have any drift. You will find the 1209s and 1208s units with the Schemflug springs will drift from heat/cold expand from time to time so the fixed units can have less drift and are more solid.

Also put a some silicone sealer on the yoke to keep it fixed and rigid.
At times I have noticed when the yoke ages it will pull back and the plastic will not be fixed anymore in relation to the tube glass. To test wiggle your deflection yoke if you get any play you can bet you will have nice convergence drift. I loosen the yoke and push up snug being careful not to rotate it. Then put a dab of silicone sealer to keep it rigid. I stolid this idea from when I retube Marquees and CRT monitors I have taken apart and they put so much glue on the yokes its crazy! Not sure why Barco never secured there yokes. If you look at a early 1100 model I noticed barco bolted the yoaks down! Why they stopped this I don’t know.

In the factory Barco set the angle of the tubes in the 1209 and 1209/2 units with a spacer. I have this spacer however when you get rebuilt tubes they are usually set in flat and this causes a lot of focus issues. The angle they used works well for 90% of install applications and typically no washers are required.

GREG

I have made this washer placement picture for ac coupled lenses.
http://www.dvdplaza.fi/forums/attachment.p...01&d=1095853469
It works very well for ac lenses.

But I remember that with my RD801s LC-lenses it was needed to make corrections to opposite direction. I thought it's because now you make corrections after one lens (C-element) and picture is already turned round (?) horizontally and vertically...

NICE wow you guys really do good work!


GREG