Got your PM, but let me reply here too.
First, I have a WHITE screen (Seymour AT screen), 16:9, about 115" diagonal. Gain should be about ~0.8 to 1, and pretty color neutral.
My surrounding is NOT ideal though, as I have white walls, and a dark brown hardwood floor (although that is about 2 ft below).
When I do my calibration (and watching movies), there is no other ambient light. I had black-out shades on all windows so that at least give me a semi-batcave environment.
Now, when I first bought my PJ last June, I did my calibration using i1D2 profiled to ColorMunki Spectro. It takes a LOT of time and tweaking on the RGB gain/offset. For the Gamma, it does not work on the previous FW, but with the latest chassis, I did find it finally works. However, LG Gamma control is quite unique, in that it is not in 10% advancement, but in 12.5%... It makes things difficult because MOST calibration disc does not have pattern for 12.5%, 37.5%, 62.5%.. Also, the gamma control is not "pin-point". When you change say 37.5% GAMMA, it sort of affect both 30 and 40%. Anyhow, it takes a while for me to get to a somewhat GOOD setting.
Now, since then, I have also added a DUO
That makes things a LOT easier to change GAMMA and RGB settings much better. So, I now did all my changes/tuning using the DUO, instead of the PJ setting.
I can certainly share my settings here, but A BIG word of caution and disclaimer is that my setting is VERY UNLIKELY going to be the perfect setting for you... We have different screens, different room environment, and probably also the different lamps/hrs.
Below is based on my notes I did for calibration back in Oct last year:
Brightness - 43
Contrast - 51
Tint/Control - 0
Color - 34
Black level - HIGH
Contrast-R/G/B = 7, -10, -6
Brightness-R/G/B = 0, 1, -5
CMS (RGBCMY) = 11,13,12,8,6,4
Gamma - LOW (user)
I did not note down the GAMMA setting, so I will probably have to turn on my PJ when I get back home and let you guys know later.
I also use AUTOIRIS=1 when I watch movies, but when I did my calibration, I use manual IRIS=16 so I can get my gamma correct. My gamma preference is 2.3.
I also do not use any TruMotion, and set cinema mode = ON (24ps).