It's not supposed to give a reflectance of "middle gray". It's supposed to
give the same reflectance as is average for undeveloped film emulsion. As to
why the silvery reflective spots on a black background, this is my best
guess:
Paint doesn't last well on high speed, fast winding curtains, especially for
50,000 to 100,000 snaps. Further, maintaining the same gray from batch to
batch may be problematic. Further, obtaining a specific reflectance is
easier when you separate each and control their respective areas. I note
that gamma calibration of most monitors involves comparing some particular
shade of gray (or the primary colors for individual color gamma) with a gray
composed of black and white (or dark gray and light gray) pixels. One
adjusts the gamma until both appear the same from a distance. The black and
white mixture is considered the _standard_.
Any comments?
Regards,
Bob...
--------------------------------------
"Those who say that life is worth living at any cost
have already written an epitaph of infamy,
for there is no cause and no person
that they will not betray to stay alive."
Sidney Hook
From: [EMAIL PROTECTED]
> Hi, gang.
> I was thinking the other day (yes, sometimes I do) about
> the pattern in the LX front curtain. It's supposed to give
> a reflectance of a middle gray, right? Then, why to use
> white and black points pattern instead of a regular uniform
> gray paint? If somebody has the answer, I'm all ears (in
> this case, all eyes)
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