I got the Epson Powerlite 720 a week ago. I'm very new to projectors and such and have spend almost a full day looking this stuff up, but would still like some help from your experiences/knowledge.
The projector is now firing at a white (very smooth) drywalled wall which is indented in and surrounded by some moulding to make it look pretty (my father-in-law's idea...). When I set the projector to Theater Black 2 (I assume this to be the best setting without blowing things out of wack), I see that in the projectcentral review, it states the projector then works at 331 ANSI lumens (1600 lumens for this thing is only in killer Dynamic mode).
So, here are my dimensions and thoughts, and some of the questions I have are listed below all this.
Room: 19'3" L x 12' W (so fairly narrow and long)
Screen indent: 91"W x 61" H (about 2'6" off ground before it starts)
Projector distance: 15'3" away and about 7'6" above ground.
I would like to fill up that screen-indent area with the most I can, so I'm guessing that would be a 106" (52" x 92") without being much too tight. That translates to a screen with 33.22 square feet. Also, to get that sized screen from the distance I have the projector would mean the projector is operating at 1.56x zoom, which I'm assuming translates to a loss of 22% ANSI-lumens, as " At the maximum telephoto setting, the projector loses approximately 45% of its total light output." (from projectorcentral). So that brings the ANSI lumens down to 258 (I assumed the drop in light output is linear, and though that may not be the case exactly, I don't think it will through the numbers off too much).
So, with the formula I see everywhere:
ANSI-lumens of your projector / Square footage of Screen * Screen-Gain
= Image brightness in foot-Lamberts
To get an screen between 12-22 Ft-L, I'd need a screen-gain between 1.55 and 2.83 - maybe the Da-Lite High Power 2.8 gain surface. This is in a completely dark room. The projected image now looks dim and definitely lacks punch.
1. What is the typical gain of a smooth white wall?
2. Is the lack of punch the fact that it's dim, or not against a screen of some kind, or just the projector; though I doubt the latter based on the reviews I've read for it.
3. How come many people seem to be projecting their Epson with Theater Black 2 (or similar projector) with a similar size, yet don't seem to mind that they don't have a screen with a decently high gain? Are my numbers wrong (and the wall is very low in gain)?
4. Recommend making my own screen from some of the DIY guids out there? Can I get such a high gain with it?
5. Do you recommend I seek for 2.8, or do you have suggestions go to to something like 2.2 (and where can I get something like that)?
Thank you so much!