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Discussion Starter · #1 ·
I can understand a gray screen that absorbs a certain amount of light; a constant fraction (%) regardless of the incoming light intensity.


However, if I understand correctly, the Firehawk absorbs more of low intensity light (dark grays) than bright light.


It works like a Grayhawk for low intensities but like a white screen for high intensities. Thus, wouldn't that mean that the screen "gain" depends on light intensity?


That is quite amazing.... How does that work?
 

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The quick answer.


Optical crosstalk makes contrast ratio pattern sensitive. A gray screen minimizes the pattern sensitivity by preventing re-reflected light and increases perceived contrast by makiing the screen darker than the surroundings. Its not really non-linear in the common terminology of optical physics.
 

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Discussion Starter · #4 ·
I am not sure I understand your answer. Do you have some reference?


Let me give a simple minded thought experiment: I am not sure how much light is reflected by a gain one screen (e.g. white wall); lets assume 10%? Thus, if I would plot reflected light (y) vs. incoming light intensity (x), I expect to get a straight line at y=0.1.


Now with a FireHawk, would I get a relationship that starts at y=0.7 ("gray screen") and ends at y=1.3 (gain =1.3 for FireHawk)?


Can the properties of a FireHawk screen be mimicked by an optical "filter"?
 

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A neutral density filter somewhat mimics the effects of a gray screen. Either way you will alter the variables of perceived color (hue, chroma, and brightness) of the projected image.
 

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Discussion Starter · #6 ·
yes, but the neutral density filter is "linear" (e.g. would give a straight line as described above).
 

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When youhave a reflective surface.. the light is reflected off of that reflective surface. If that material is translucent, to semi-translucent.. then it still reflects.. to the human eye.. relatively the same amount of energy. This is aslong as the surface is reflective.


That same material, when no liight is shone on it.. will appear, to the eye to be relatively translucent, and any material that is backing it, will be the 'tonality' or 'black level' that will come through and be registered by the eye. The Firehawk and Greyhawk are constructed along these standards and designs.


The Goosystems screens are very, very similar. I was playing with these effects and designs long before this currnet round of grey screen design. I was just a bit slow out of the gate. I was playing with silver back, matte, white, black and grey ..covered with various translucent coatings, etc. all kinds of combinations The most I ever had was 19 screen designs in the house at one time.
 
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