Digital BW, The Print

Roy,

> I think its particularly useful if the examples are related to how we
> humans perceive light and/or sound.

But that has nothing to do with dynamic range being dynamic range.  That
only has to do with OUR perception.  We are NOT the film, we are NOT the
film scanner, and the perception of film and scanner are VERY important in
producing the image that WE see...it takes more than just what WE perceive
when we look at the final print.

> DynRanges of digital volt meters
> or whatnot may be useful to you but don't help the rest of us "get it".

Dynamic range of both film and scanners IS useful, and I've illustrated
those.

> > > Similarly the human perception of both is also completely
> > > continuous.
> >
> > This is the concept you seem to not be understanding.  You can have two
> > sounds/tones that ARE completely different (as determinable by
> SOME sensing
> > device), but YOU perceive them (or some sensory device) exactly
> the same,
> > indistinguishable from each other...no matter how hard you try.
>
> Sorry to sound snide, but "So What?".

Sigh.  That's the root of our disagreement.  You don't get the significance
of this, and how it relates to dynamic range, and that's why you don't
understand my use of dynamic range, and also why dynamic range (as I've used
it) is important as a specification/interest/property.

> > That IS the
> > concept of dynamic range plain and simple.

> If this is DyR and its unperceivable, then "So What?".

I DID NOT say it's unperceivable at all!  It is the "limit of
perceivibility" (over a specified range), say in a sensor systems (like your
eyes).

> It is NOT the OVERALL range, but
> > describes what the PERCEPTIBILITY is within that overall range.
>  Simple as
> > that.  It's relative within the range (in the analog case), NOT
> absolute.
> > In the digital case, it is absolute.
> >
> > VERY simple example.  You have one sensory system that can
> perceive a 1/10th
> > range difference.  Another that, using the EXACT same range,
> can perceive a
> > 1/100th range difference.  The one that perceives a 1/100th
> range difference
> > has a higher dynamic range.
>
> Sounds more like higher sensitivity.

ER, yeah.  BUT sensitivity is not based on the overall range, as dynamic
range is.

Sensitivity doesn't give you any ability to compare different
"systems"...but dynamic range does.  You could have a system that has a huge
range, but really low sensitivity...and a system that has a smaller range,
but very high sensitivity (just like positive film vs negative film as one
example ;-)...and neither the range, or the sensitivity (by them selves)
mean anything when trying to compare the two, but the dynamic range, as I
have used it, does give you a meaningful comparison.

<snip>

> Do I have to
> reprint all the specs?

Providing your measuring equipment was "better" than the noise in the amp,
no.

You give me "so what"'s for things that are very important, and you just
dismiss them!  I am sorry to say, but I really feel like I'm wasting my time
if you're not going to try to understand why those things are important.

One thing that would be interesting (at least to me), and since you seem to
have a lot of time for research ;-) would be to find out the origin of the
term "dynamic range", and what it meant to the person/people who first used
it.

Austin