Originally Posted by ccool96
If you are zooming and not using an A-lens then you figure the screen size width but with an aspect of 16:9, matching the projector panel.
So with a 140” wide screen (scope or 16:9) doesn’t matter with the zoom method. With a .8 gain and 2500 lumens gives you 26fL to fill the entire 140” screen width. You would have the same 26fL if you had a 140” wide screen that was 16:9 aspect ratio as well.
You really won’t be able to clamp down on the iris at all.
Even with the Lumagen DTM, personally I consider 30fL the bare minimum for HDR content. ...
My screen will be CIH (side) masking. So as 2.40 it is 140" x 58.3"=56.6 sq ft native. As 16:9 , it shrinks to 104" x 58.3"=42 sq ft. The native JVC panel is 17:9 ratio. Lumens to work with = 2000 lumen (2500 calibrated in high laser * 0.8 gain).
Sorry, I do not understand how you calculated 26 fL for both the 16:9 image and 2.40:1 image (latter with JVC zoom to scope function).
My calculation for a 16:9 image is 2000 lumens/42 sq ft= 47.7 fL.
I do not know how to calculate for 2.40, as I cannot conceptualize the light loss using ZOOM. I assume 2000/56.6=35 fL is not accurate?
Sorry guys, tried to google this stuff but still cannot find clear explanation of the math.
Originally Posted by MDesigns
Did you use the whole 17:9 panel area when calculating by hand? The projector illuminates the whole 17:9 area even though your screen is scope. With the DCR you could get all of the lumens to scope format.
Also, throw distance is measured from the lens. How long is your room from the screen to the back wall?
Not sure how to alter the above calculation to reflect its native 17:9 panel, projected to 16:9 and 2.40 ratios?
I realize throw is lens to screen. My room is 19' 9" long (237"). I will lose 4" (front wall to screen surface), 8" (behind projector for connections), and 28" (projector length itself) = 197" throw distance.
Originally Posted by markmon1
Why not dump the 0.8 screen and go with a st100 or even st130?
I need an acoustically transparent screen. My front/main seating is 10' away from screen (2 x screen height). The Stewart ST100 and ST130 only have microperf available, which will be visible from my seating distance and degrade the picture. The Seymour screen Enlightor Neo is a woven fabric, and also will offer better contrast.