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I have a BG800 with about 6K hours on the tubes which show some minor burn, but not really badly. Normally, I've been running it at a contrast level of 50, but boy do somethings look really great at 60 or even 65. I'm planning on upgrading in probably another year or two, so absolulte max tube life is not important to me, but I want to be sure it'll last at least that long. I have a decent but not fancy Da-Lite screen that is probably at 1.0


So, what's recommended?
 

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A good way to adjust contrast is to take a gray scale 10 IRE steps and display it. Adjust the contrast so that you can see distinct differentiation in the last two patterns at the bright end. If you have to much contrast the last two "white" patterns will look the same and you will be crushing the whites.

If you are using a HTPC, put the patterns up from your desktop and set the contrast on the projector. That gives you a reference and you should not have to touch the projectors controls again. Once complete plop AVIA into your DVD player putting up the gray scale steps and adjust the overlay.

Do the same for your brightness just pay attention to the black first two or three patterns.


Terry
 

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Get your color balance where you want it to be, with each tube giving a nice delineation of contrast range. Then, run your contrast up until the tubes start to 'bloom' ( defocussing, fuzzy image, etc) right at the point where they start to bloom...then back down 10 notches from that point. On my PJ, the way it has been set up.. this occurs at a setting of 50 (contrast scale of 100). So, I run the PJ at 40..for that particular source, which is my HTPC.


The settings are very source specific. The variation from PJ to PJ is very huge. Each PJ has been set up differently, and is used with different signals. Screen size, or placement has nothing to do with anything. It's all in the bloom and smear of the tube. Get to the break point, and back down 10 notches (if it is a 0-100 scale for contrast range).


Do not use internal PJ generated (but you can use them for the initital set-up, of course) test signals for this bloom and smear testing.. use the signal you will be viewing. Your HTPC, Scaler, Satellite box, and DVD player, etc, will all load the CRT projector differently. A setting must be 'understood' (by you..and manually adjusted, unless your PJ does this for you when you switch sources and resolutions...check for this) for each device.


Even a HDTV signal on a sat box is TOTALLY different that a 'regular' signal on the -same- sat box.


This is how you keep your tubes for a long time.
 

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I have a Barco BD801 and I set my contrast using the patterns on the AVIA DVD and ended up with setttings of:

Contrast - 53

Brightness - 61


Dave
 

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Jeez, I have a sony 1270q that I just aquired and I run the contrast at about 81. Looks great, but is this level harmful to the tubes? Can I set it lower and use my Radeon overlay controls to give desired contrast? Don't want to cook my tubes and I am new to the projector scene.
 

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Guys,


While you can't use someone else's numbers for a direct comparison because of the different manufacturers, models, sources, and setups, Barco's in general DO like high contrast settings.


So while Marquee owners may find that the average contrast settings are between 35-55 (guessing here), Barco averages are higher: Probably in the 50-75 range.


I run my BG800 on a 8' wide 1.4 gain screen at 65 contrast (Radeon HTPC source).


Again, don't use someone else's numbers to compare.... just stay away from blooming like Ken mentioned.


Kal
 
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