Digital BW, The Print

> Never mind about that, I guess when you said "the way current scanners
> are designed" you were correct.

OK.

> I don't know about 3.2 drange, but how about the Microtek 300Z or the
> Apple One Scanner.

Got the specs for them?

> > It IS possible, I've already "figured it out", but, as you say, it just
> > isn't necessary.  It's actually very simple.  The data out of
> the A/D does
> > not represent integer density ratio values, but fractional density ratio
> > values.
>
> Why do they have to be integers?

Because that's what ratio values typically are.  Ratios are relative to 1.
You set 1 to some density value, and when something is twice as dark, that
gets a value of 2, as in 2:1.


>
> > > I have taken issue with the term dynamic range. Scanner companies use
> > > it to mean their scanners capture more information.
> >
> > The term "dynamic range" has been around long before scanners, and has a
> > fixed meaning in the engineering community.  Because it is
> > misrepresented/misunderstood by some does not change the
> definition of it.
>
> The dynamic range of sound does not relate to the intensity (volume)

Actually, it does.  It's typically measured just below clipping.  Dynamic
range is very simple.  It is the largest signal over the smallest
discernable signal.

> > > If a
> > > scanner could really capture 4.5 density-range in a 12 bit space,
> >
> > As I've said, you CAN capture (if you design a scanner to do
> so) any density
> > range into 2 or more bits...BUT...the values you get are NOT
> integer density
> > ratio values.
>
> Who says they have to be integers?

See above, and that's the way they are designed.  What advantage would you
get by not using integer density ratio values?


> > > then
> > > a normal negative's range would have to fit into a much smaller space
> > > than 12 bits.
> >
> > For that particular scanner, IF that scanner was designed to
> operate that
> > way, that could be true.  Perhaps the scanner could expand the
> data to fit
> > the entire 12 bits.
> >
>
> Wouldn't this be something we would want?

No, not if YOU wanted to manually set the setpoints.

> > > Which would mean that, with that negative, that scanner
> > > would actually capture less information than a 3.3 d-range, 12 bit,
> > > scanner.  Does this make sense?
> >
> > Only if the scanner was designed to operate that way.
>
> I am thinking that this would be true with the scanners on the market
> now, yes?

No.

> >
> > > That is one of the reasons I think they should have called it density
> > > range. And left the term dynamic range to something more along the
> > > lines of bit depth.
> >
> > But they are both the exact same thing.  Density is a ratio, just like
> > dynamic range is.
>
> Yes and no, density is a ratio compared to the darkest one can see.
> Dynamic range is a ratio compared to the sublest change one can see.
> Because of the way scanners are made, they end up being the same.

It isn't because of the way scanners are made...it's because of the way CCDs
measure light, as well as being convenient and make sense.  What the heck is
the problem with using integer density ratio values?  Can you propose some
other methodology that can be standardized so all data files pretty much
"mean" the same thing?  Your arguing about why car wheels are round IMO.
You could make them something else, but why and to what advantage?