Originally Posted by SHMO
My PJ is currently 12' 11" from the screen, and it hangs 6" below the top of the screen. It is variable in height, in one inch increments.
My front row viewing is approx 13' 6" and the back row is 18' 6". The seating can be adjusted as well, as I am planning to re-carpet, and the riser can be nudged back or forth. I have the ambient light controlled pretty well, but I do have a white ceiling and some (not dark) elements in the decor. Gaming is something we use the theater for, as well as casual party viewing such as sports and events, where dim lighting needs to be present.
On an 122" screen a 4K image might not be that different from 1080p from that distance. There is no consensus on this issue, varies person to person.
It might be worth getting a 4K unit because it can accept different type of signals from whatever source is being used.
If you're watching a lot of sports a DLP projector will have better motion handling. But 3LCD on Epson's are also fine.
DLP models generally have a positive offset, which means the center of the lens sits above the top edge of the screen.
For an 122" screen for example an UHD50's center of lens would need to be 3" above the top of the screen.
If you decide to go DLP, check how much the mount can go up.
3LCD Epson's are generally more bright than the DLP's, but the DLP's are still bright.
DLP: Benq HT2050A
3CLD: the models DunMunro mentioned, and maybe the HC3100 and HC3700.
The HC3700 is one of the brightest home cinema projectors.
DLP: Optoma UHD50/51/51A/51ALV/52ALV, Benq TK800M/the upcoming TK850, Viewsonic PX727/747 4K.
3LCD: Epson HC3200 and HC3800
The HC4010 is a unit with better looking picture, but is ~25lbs. and the mount would have to be changed, or placed on a shelf .
Depends what is on sale, and what you prefer.
Check the specifications to make sure it fits the setup. Projector Central Calculator is a great resource for dimension calculations.
The HC2150 mentioned above: