Originally Posted by Yukichon
We then put in the 3/4" OSB flooring. It feels pretty solid, so do I really need to double it up?
Also, another question.....I'm probably going for the JVC RS4910U and was wondering how far back my PJ placement should be. I'm thinking of 140" 2.35:1 screen. And whilst the ceiling is open i want to make sure I have dome good securing points between the rafters.
Somewhere I read that the 2 layers of 3/4" OSB has a lot more to do with Sound & Reverberations, than it does with Structural integrity.
In terms of PJ Placement... Mike at AV Science gave me the following information:
130" Wide 2:35:1 Screen is largest he would recommend for the 'best' picture if using an Acoustically Transparent Screen (which limits Screen Gain some and causes some light loss). Screen Lens to Screen 15' back, Screen Post Center 15'9" from Screen. On high lamp this is 17 foot lamberts, in a totally light controlled room - target is 12-16 foot lamberts.
144" Wide 2.35:1 Screen - larger than recommended.... but 16'6" from Lens to Screen, and 17'3" for Post center to Screen. This would be 14.1 foot lamberts for a brand new bulb. As Doublewing states though, this will cause more frequent bulb replacement or degraded quality with reduced light output.
I didn't ask for 140" wide, but IF (and I don't know this) the above relationships are linear, then the projector lens would be at 16'1" for that size screen. If you are thinking non acoustically transparent, that gives you more latitude on the screen size. I might call Mike Garrett at AV Science and talk with him about it, and they of course sell the projectors as well.