In my "man cave" HTR with no windows I use the Cinema mode with no to very dim lighting and I'll use the living room or natural mode when watching sports with some lighting on. I never use dynamic. Generally speaking the lamp life will be prolonged using the less bright modes in eco mode. But the "correct" mode to use really depends on several factors:
1) size and gain of screen
2) projector distance from screen
3) ambient light
4) age of the bulb (as all bulbs will dim somewhat over time)
There are online calculators that you can use to interpret the ideal settings based on the above data.
thanks for the reply - could you point me to the calculators?
Here is my info:
1) 120 Elite CineWhite 1.1 gain
2) 15.5' throw distance
3) light controlled room - some ambient light as its a shared game room/theater room
4) 25 hours logged on bulb