CurtPalme.com Home Theater Forum

[Jaysunvzw]

I've got the basic install very close. Tubes are Horizontally good on the cross bar. Focus is decent. Having problems with final convergence. Film on S-video looks decent but occasionally I notice off color on the edges as I know the convergence is still not perfect. Do I just keep doing it over and over? Also I'm trying to set the output for 16:9 ratio on a 72 wide 40.5 high screen. It looks good during convergence but the movie Kingdom Come widescreen still leaves 4 inches at the top and bottom. The odd part is the FBI warnings at the beginning of the movie fill the whole screen. I'm off to get some BNC adapters for component. Thanks for any help.
Jason

[scotha]

What barco do you have? The bars at the top and bottom of kingdom are normal the aspect ratio of that movie is probably 2.35 to 1 and your screen is 1.78 to 1. HD television broadcast will fill your screen. Look on the back of your dvd's at the aspect ratio, 1.85 to 1 is common and will fill most of your screen 2.35 of 2.40 to 1 will not. Use your RGB inputs if you can.

[ecrabb]

Yep. Kingdom Come is 2.35:1, so will be approximately 72x30.5... leaving 4.5 inches at top and bottom. Accounting for a little overscan, 4 inches is probably about right. Here's a great article all about aspect ratios:

http://www.thedigitalbits.com/articles/anamorphic/aspectratios/widescreenorama.html

As for your setup... there are a few things. First, make sure you read your projector's install manual (with setup procedure) several times. Next, yes... As a newbie, you'll need to do your setup a lot of times. You'll get better and better (and faster) at it each time. The first time is a struggle, it's slow going and you end up with just a watchable picture. After you do it a few times though, it'll get better. After you've done it several times, you can crank through much more methodically and the results will be far superior to the first couple of times you did it.

One thing that really helps is when you understand how the geometry and convergence controls really work together. It thought there was a guide here somewhere on "geometry and convergence theory", but I can't find one. We should write a guide for newbies.

Basically, the geometry controls kind of work in pairs: size and linearity, keystone and skew, bow and pincushion. When you do setup, to get the very best setup, it's very iterative. You adjust one control, then the next, then go back and tweak the previous control if necessary, and keep making it better and better.

Make sure your projector is perfectly level and perfectly centered on and square to the screen. Any physical misalignment will make focus and convergence much more difficult.

A typical geometry/convergence setup might go like this (assuming optical and electronic focus is already done):
A. Tape some string on your screen at V and H center so you have a reference for exactly where screen center is, and what perfect horizontal and vertical in the center of the screen.
B. Turn off blue and red tubes to work on green only.
1. Adjust raster center on screen center.
2. Adjust V and H size until the center of the image matches the screen centers (the top and bottom will be larger/smaller than the screen).
3. Adjust V and H linearity to balance L-R size properly (you may have to tweak size again - see the 'pairing' effect?)
4. Adjust V and H keystone to make the edges of the raster horizontal and vertical
5. Adjust V and H skew to make the overall raster level and plumb (tweak keystone again, then skew, etc.)
6. Adjust V and H bow until the only bow left is pincushion
7. Adjust V and H pin until all lines are straight (go back and tweak bow again, then pin until all lines are perfectly straight)

Once the green is as perfect as you can get it, turn on the red raster, and start the whole process over to make the red match the green. Repeat for blue with red or green raster off (green off will probably be easiest.) Turn contrast down to prevent burn while you work, and to make the set sharper. Turn all three rasters on and tweak if necessary. Once you've nailed geometry down the best you can get it, then you can use zone convergence sparingly to adjust zones individually - usually in the corners (I assume the 701 has zone control - I'm not a Barco guy).

Work in complete darkness if possible, and walk right up the screen or use short-focus binoculars if you want to sit on your arse. Do it all with the highest resolution you'll use selected and tweak lower resolutions separately if you'll use them (probably 1080i for a 701).

Hope that helps!

SC