[filmscanners] RE: IV ED dynamic range... DYNAMIC RANGE!

["Austin Franklin" <darkroom@ix.netcom.com>]

Hi Laurie,

> The whole damn thing turns on the phrase, "acceptable signal level."
> Austin, if I read him correctly, holds that "acceptability" is defined as
> being above the noise level at the low end;

If you read the definitions used, both "terms" used "acceptable signal
level".  When used as "minimum", it, to me, means noise, when used as
maximum, it mean the maximum amplitude of the signal (before clipping, or
saturating or whatever...where the signal is still valid).

> Julian probably implicitly
> accepts this also.

I do not believe this.  What others, who do not believe my understanding of
dynamic range, believe is that dynamic range is not based on noise, but on
the largest value of density the device can detect, minus the smallest
density value the device can detect, basically, dMax - dMin, and there is no
noise in the equation...  This is simply the density range, and is not the
dynamic range.

Here is what he said:

"DYNAMIC RANGE on the other hand, is the smaller range within the Density
Range that the scanner can capture AT ONE TIME i.e. dynamically i.e in one
scan.  It is the instantaneous range the scanner can handle."

Which, of course, has nothing to do with what I believe dynamic range is.

Austin

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