http://farm4.static.flickr.com/3590/3419636203_83ef7859a7_b.jpg
What made you think that?
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W
. | ,. w , "Some people are alive only because
\|/ \|/ it is illegal to kill them." Perna condita delenda est
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Don't you mean tort that?
Colin D.
Let's rephrase that. *Every* camera produces noise.
Reading data from the sensor produces a signal even if
the the lense cap was on and no light at all hit the
sensor. That is a major component of "read noise".
And the sensor output is an analog signal, which is then
digitized, which adds "quantization distortion" (again,
even if there was no light hitting the sensor).
Hence there is always noise with every image made by any
camera. The real question of course is can it be seen,
and in fact proper exposure at low ISO levels will
almost totally mask the noise. As the ISO is increased
the signal level from the sensor, but not the noise
level, is decreased, and it becomes easier to see the
noise.
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Floyd L. Davidson <http://www.apaflo.com/floyd_davidson>
Ukpeagvik (Barrow, Alaska) fl...@apaflo.com
I tink tow.....
So we pretty much agree!
Of course one distinction neither of us mentions is that
at exactly what point the noise becomes visibile is
different with each film and each sensor.
So I have an older Nikon DSLR that's just barely useful
at ISO 400, another that is "noiseless" up to ISO 800,
and one that is still reasonable at ISO 4500. I might
not refer to any of them as "noiseless", but shooting at
ISO 4500 and not being blown away by noise is just an
incredibly mind boggling experience for anyone who used
film! :-)
If you're happy with the noise levels of a particular camera, then
there's no need for you to worry about it.