Originally Posted by BrickTop
Yet again a fairly large descrepancy in lumen output numbers. PR got 696 (717 full zoom) calibrated with lamp on bright iris at 6. PC measured 945 at full zoom, calibrated, in bright lamp with iris at 6. So we have a fairly high descrepancy of 220+ lumens. Makes it really hard to determine ftl on a large screen. Has anyone here done any lumen measurements of their PJ at home to determine which site has more accurate lumen readings? I don't mean just this PJ, but any PJ.
Your right their info is flawed, lumens are not a universal thing they need to supply the screen size and gain they were using. Knowing whether they're using calman or another color sensor device with program would be good to know also. Light level should be tested with a light meter. They should supply the light info in Lux or Ftc so users can calculate what their lumens will be.
In bright lamp, manual iris opened my light meter reads a solid 37ft-candles. My screen is 106" diagonal 1.0 gain. Max brightness for this screen would be 1121 lumens. Low lamp 30ftc = 909lumens on my screen. I'm not going to take the projector down so those numbers are close to max zoom, not as high of a reading as it could be but close enough.