Originally Posted by d3coy3d
Do you guys think a 166" HP (2.35 2.4 gain version) screen would be to much for this PJ at medium throw? Light controlled room PJ at center/eye level
Depends on how bright you want the image, whether or not you'll be using an anamorphic lens, and if you want to run on the lower lamp setting.
My screen is very similar in size to what you're looking at (mine is 155" x 65" 2.40:1 versus your 153" x 65" 2.35:1). The old HP material offers me a bit more gain in my prime seats. In cinemascope mode with calibrated settings, I'm getting about 16 Ft-Lamberts on the normal (lower) lamp mode with the iris wide open, which is a brightness level many viewers like. I'm only able to get to this level because I have a fairly fresh and good performing lamp, because I'm near the shortest throw, and because of the level of gain my old HP fabric offers (about 2.6-ish from my viewing position).
I find great satisfaction above 12 Ft-Lamberts with the large image size and my close viewing distance. I turn it up to 14-ish Ft-Lamberts for darker features (i.e. the dim Harry Potter films), but don't often go brighter. But that's my preference. Some like it substantially brighter.
At 153" wide, if you're not using an anamorphic lens you'll require the projector to be illuminating about 92 square feet when throwing a full-width image (works out to about 86 x 153). If you can figure out what sort of gain you'll see from your main seating, you can do a little math to figure out what sort of lumens from your projector will work for your desired brightness.
If I'm doing the math right, this is what I see:
Assuming you want 16 Ft-Lambers
Assuming 2.2 gain from your prime seats
Assuming 92 square feet illuminated for full-width projection
16 / 2.2 = 7.27
7.27 * 92 = 669 Lumens
That would most likely be unachievable in "Normal" bulb mode, but should be easily achievable in "High" bulb mode.
If you use a high quality anamorphic lens, you'll gain some brightness, and the equation changes again. The right lens may provide enough brightness to run your setup in "Normal" bulb mode.