I haven't seen a HP screen in action so I'm trying to work out all the theories.
I've filled out the spreadsheet and found that I should be getting about 2.1 gain (with the HP 2.4 gain screen) from my viewing position.
So based on the formula: FtL = lumens x screen gain / sq. feet of screen
JVC X35 / RS46 has about 700 calibrated lumens when brand new. The 133" scope screen is the equivalent to a 140" 16:9 screen in terms of width so that equals:
700 lumens x 2.1 gain / 60 sq. feet = 24.5 FtL.
If the standard is 12-16 FtL, then I would imagine this would be a fairly bright image.
However, If I control the manual Iris and use the low lamp mode and get say 500 lumens, then I get 17.5 FtL.
So my question is, given I will be shining a relatively low about of lumens on the screen, with FtL of 17.5 would I expect the colors and black levels to be fairly accurate? Over time, this will dip into that 12-16 FtL range and I can manage the Iris to keep things consistent.