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In the most recent SGHT TJN provides calibration details on the SIM2 HT300 PJ. He mentions that the gain on the Firehawk is 1.08 not the stated 1.35. He compared the light measured from a StudioTek to the Firehawk to reach this conclusion assuming the StudioTek is 1.3. I think his conclusions are flawed because he mentions that the room is not a black hole and re-reflected light can bounce off the screen. Then it is no surprise that the total light coming off the StudioTek is greater. In fact he reports that the contrast ratio is different on the two screens comfirming that re-reflected light must be a factor. I have two comments.


1. To accurately measure the screen gain one must make sure that there is no re-reflected light at all.


2. The screen can't change the contrast ratio of a projector and if re-reflected light is eliminated, the CR should be the same on both screens.



Any thoughts?


John Moschella
 

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If I remember correctly he had taken both on-off CR and ANSI CR. The Firehawk would definitely improve ANSI CR, but on-off should have been the same. I remember his ANSI numbers improving, but I can't recall the on-off numbers.


If you are talking about his on-off CR measurements, the room should not have had an effect on the readings.


I'm not confident about his relative gain numbers either, unless he was very close to on-axis for the Firehawk the gain fall-off may have contributed to the lower gain reading.


Regards,


Kam
 

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It would take a lot of re-reflected light to change gain numbers that much. A horrible room would give about 10% a bad room would be 1% and if the walls are darkly colored then it will be less than 1%.


But 1% is enough to interfere with an ansi contrast measurement but wouldn't be enough to change the gain measurement be .27 or whatever.


-Mr. Wigggles
 

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I asked the same question here . Mr. Stewart had this response:

Quote:
Originally posted by Don Stewart
When I first read this I scratched my head and then thought about it for a few minutes. The conclusion that I came up with was that the projector was table top mounted and a percentage of the FireHawk's angular reflective gain was passing over the reviewer’s head.

Regards,

Don
It really is just awesome to see that kind of feedback direct from the manufacture here. Can’t wait to see a FireHawk in action. Preferably very soon in my HT.

-jeff
 

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For what it's worth,


I took these notes some time ago from SOMEWHERE. I like to jot stuff down as I read. I assume these measurements to be correct.


FireHawk gain = 1.36

GreyHawk gain = 0.96

Both screens are grey; Greyhawk is the darker of the two.


I was also thrown off at the article that mentioned the FireHawk to be 1.08 gain. All I can tell you is that I have one and it kicks! The screen, the build quality of the frame and the manufacturer's backing make this a win-win purchase. Now, if the damn wrinkles would just go away...
 
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