White or Gray for this install location

[collinong]

I'd appreciate some input on what color of screen would work best in the locations outlined in red on the picture:


(click for big version)

I'm thinking fixed-frame screens mounted on the walls where I drew the red boxes. The size is about 96 inches wide by 75 inches tall for a 4:3 diagonal of ~120 inches. The first set of hanging lights will be removed and the second set either removed or raised up to about half their current drop. The projectors will be mounted a bit in front of where the second set of lights is mounted to the ceiling. The projectors will likely be Epson PowerLite 4300, manufacturer specified as 5200 lumen.

The biggest problem is the triangular skylight. I know that light from that is going to hit the front of the screen somewhat and wash out the image. There is a shade for it but it doesn't block 100% of the light.

So I'm thinking of going with a gray screen to increase contrast to mitigate the skylight. Is this the right direction to go?

I've found this screen that will fit and we can afford. It claims a 0.9 screen gain, but will the 5200 lumens be bright enough to push through the gray?

Any thoughts on this setup?

Thanks in advance.

[collinong]

so, any experience using gray screens in an environment like this? wondering if it really helps mitigate the overspill of light from the skylight.

[collinong]

i put up some white blackout cloth at the proposed screen location and set the epson 4300 (5200 lumen) projector on a ladder to test out the image in various configurations with the lights on/off and skylight shade open/closed.

the black levels were definitely a bit gray when the lights were on and the skylight shade was open, but the image was clearly visible and easy to read. when you closed the skylight shade and turned off the front lights, it was much more contrasty and vibrant. but there wouldn't be a real problem even with all the ambient light, just a image pickiness problem.

i probably will go with gray screens to help the contrast during ambient light since i am picky about such things.

also, due to the Epson not having DVI or HDMI inputs until you add $2000 for the pro-line, i switched to a Benq SP920 6000 lumen DLP with dual bulbs. This should help with brightness as well.

[Les]

Sorry, I never saw the original post.

Generally speaking front projection screens are "white" and rear projection are "Gray".

I've personally never seen it the other way around but it wouldn't surprise me if it was.

So for front projection use the "white" screen.

[collinong]

gray screens are also used for front projection to improve contrast when there is ambient light.

the way i think of it, it moves all levels down a few notches. since the black level is defined by the ambient light, when using a white screen in ambient light, the light makes black's gray on a white screen. in the same environment, a gray screen would made the black level darker and shift everything from the projector down a few notches and improve perceived contrast. if your projector is bright enough, your white levels will still be ok but the blacks will be more crisp.

that's how i understand it. my question was to get more opinions from people that may have tried out gray screens in this type of environment.

[collinong]

here is a picture of the end result of the installation:



I'd say it worked out pretty well and is a vast improvement over our previous setup and for an expenditure of only ~$8300 with about $530 of that being lift rental. Took about two weeks of long days using volunteer labor from the congregation.

The 0.9 gain gray screens turn out not very gray at all. Most probably don't even notice they aren't white. Readability is still very clear with all lights on, skylight and window blinds open, although pure image contrast is compromised when the ambient light is full-on.

[[Admin] osborn4]

Looks real good. Glad it's working out so well for you.