[canavan]

The Lens program tells me to mount my BG808 at 327cm (129") from the screen (52x92). However, with the current rough setup, and an imho sufficient border of unused phosphor around the raster, I can move the projector about 18cm (7") closer and still fill the screen without problems. Should I do as the program says, and probably get better corner focus and less brightness falloff at the borders, or move it closer, and use more of the phosphor resulting in more brightness and better resolution? At about 5% difference, does it matter at all?


The brightness falloff could easily be countered with the contrast modulation option, does anyone here know which part number is needed for the barco graphics 808 (non S)? Does the installation require any soldering or have other surprises except losing input 3?

 

[EC]

I used the Barco Lens program and its recommendations when I had my BG808s floor mounted. When I moved to ceiling mount, I moved the PJ about 5 - 6" closer to the screen (96 * 54) and tilted it slightly. Do I get more brightness? Probably do but I can't tell the difference. I will admit that it was harder to focus, I had to use those shcmplug (sp) bolts much more but this was from the tilt more than the closeness IMO.

 

[kal]

Move it closer. I have my Barco moved closer so that there's only about 1/8" of unused phosphor between the image and the closest point to the edge of the phosphor.


This is not only true of Barcos - most setup programs will have you installing too far back. It's safer I suppose, but far from optimal. NEC's are probably the worst for this.


Corner focus? Sure, it may be harder to get perfect, but really, who cares if the corner focus is just slightly off for movies - it'll never be noticeable.


Kal

 

[DPB]

I'd agree with kal (as usual), I use just about all (1/8-1/4" from the edge) of my tube and there IS a SLIGHT defocus at the edges but I NEVER notice it. It's REALLY hard to get a perfect (maybe impossible) focus at all the corners. The only time you'll notice it is while the desktop is up. Movies are VERY forgiving as far as focus (and conversion) goes. I've seen my cursor like like crap but a movie looked good. Don't get TOO hung up on small details, you won't notice them.

 

[Nich]

I'm with KAL.


The corners will be in the black bars, anyways.


Nich

 

[tiger_piggy_lee]

Move at lease 8% closer as suggested by the program . They did it to allow room for imperfect installation and image shaft for various frequencies. The best way is to watch raster as you move the projector .


Don't worry about the electron hitting outside the phos.


During initial setup , Barco use the internal service program to run the CRTs at full raster for 48 hours. I saw their tech doing this when re-tube a 1209s. :