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RE: filmscanners: film vs. digital cameras - wedding/commercial photography
> > Only the color information is shared amongst multiple pixels
> > NOT the edge information. That does not make the four pixels one pixel.
> > Do the geometry. Each of the four sensors is capable of sensing an
> > entirely unique "section" of the image. Why is that so hard to
understand?
> Because it isn't true.
What part of it isn't true? Be VERY specific.
> Each sensor has a filter in front of it (R, G or B).
> That means that you have to use sensors next to it to get a true value of
the
> luminance at each sensor.
No, it means you get a different color value from a DIFFERENT PART of the
image.
> Each sensor just measures the luminance within a small spectrum.
> I think that's pretty clear, isn't it? :-)
To me it is, but your perception of how it works is incorrect.
> > Take the four pixels, a 2x2 box, and say the left two are sensing only
> > black, and the right two, only white. What are the four
> > resultant values going to be?
> Good point, because that shows the problem. You can't determine what the
TRUE
> value was at each sensor,
True value of WHAT? The color, no, but the edge information is still there.
> > Television works more or less the same way, having some
> > fraction (1/4th?) the color information to the edge information.
> Well, if you're satisfied with TV picture quality, that method works fine
:-)
It's called aliasing. To the human eye, color aliases far more than edge
information.
> But as I mentioned in the first paragraph, even the edge information
suffers
> from this "guessing" approach.
Not in the way you believe it does. I really do hate to mentioning this,
but I am a professional engineer and have been designing digital imaging
systems for over 20 years. I really do know exactly how these things work.
What is your background WRT digital imaging? Have you actually done designs
with these sensors, and you are speaking from experience? I have, and I am.
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