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RE: filmscanners: RE: filmscanners: pushing dynamic range on the nikon 4000ed--What is Analog Gain
> Unfortunately this isn't what it actually does. The "analog
> gain" actually
> changes the integration time ie. how long the CCD is exposed for.
> The longer
> the exposure, the greater the "analog gain".
Where did you get the idea (as in a source of information) that exposure
time is "analog gain"? Gain is something entirely different than exposure
time. Time is, well, time. Gain is amplification of a signal...though that
does increase over time, I don't believe that qualifies as "analog gain".
In every digital imaging device I've ever designed or worked on, gain has
specifically been the control of the output amplifier between the CCD and
the A/D, and is typically determined by calibration. It is used to offset
the variance in illumination that can occur over time.
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