Digital BW, The Print

Martin,

> The trains of thought become so fractured that they lose
> all meaning.

I know, that's why I like very short posts...but we seem to have a few quite
prolific writers here, with many nits to pick ;-)

> I do have to take exception to your deleting of
> portions of the
> previous message you are responding to without inserting a "(snip)" or
> something similar to indicate you have removed things from their context.

Understood.

> Your definition of dynamic range is
> correct and completely acceptable to me in the many areas especially
> electronics, audio and digital processing. Most importantly for us on this
> list in terms of scanning. The concept you present is not being
> rejected and
> is no way in error.

OK, I can work from there ;-)

> However, to be meaningful your concept is based upon the
> inclusion of noise
> in both the concept and the calculation. In this regard I believe that the
> concept you have presented MAY not be of interest in comparing various
> combinations of ink/paper or silver papers because the noise in
> these print
> mediums is very low and performing the calculations would leave
> us comparing
> one large number to another. In other words, once the noise
> becomes so small
> that it is no longer observable by the viewer it can be ignored.
> This is not
> to say that it does not exist but may be irrelevant.

I understand and appreciate that.

> If you can demonstrate that the noise in a print medium (I stress
> here print
> medium and not any individual print) is large enough to effect the visual
> quality of the prints and produce DyR values that help us compare print
> mediums, then I am most interested. As a theoretical debate it no longer
> holds any interest for me.

When my new lab is set-up, I will be more than happy to spend some time
doing some experiments, and, as expected, posting the methodology and
results for review.

> It is also a point of fact that in photography, regardless of your own
> opinions on the mater, dynamic range has been understood to be the density
> range Dmax-Dmin.

Oh, I do know that to be true.

> This is in complete agreement with the common
> definition of dynamic range.

Well, not with the common definition of dynamic range OUTSIDE of it's (I
believe) misuse in the photographic industry, but within the photographic
industry, I agree.  I didn't say it was correct, but I agree with your
statement.

> I also still contend that the concept that a photographic print
> has a finite
> number of tones between min and max is also an unusual and unfounded idea

Number isn't a good word for this concept, unfortunately.  It's not an exact
number I believe is cared about, but that one can "observe" (by what ever
methodology) an image has more tones than another image, rather than knowing
the exact number.  I'll have to really think about that, as the "number" of
tones will be a range I believe, and not fixed...

<er, snip ;->

> You have used the word tonality and suggested that this is in reference to
> the number of tones in a print. This in not a proper usage of the
> word which
> is:
>
> Tonality:
> 1 : tonal quality
> 2 a : KEY  b : the organization of all the tones and harmonies of
> a piece of
> music in relation to a tonic
> 3 : the arrangement or interrelation of the tones of a work of visual art
>
> This is an artistic term and not a technical one and by no stretch of the
> imagination implies quantity but simply relationship.

#3, interrelation... doesn't?  I'm not so hung up on it being a "number",
but a distinguishable difference in the number, what ever that number may
be.  Given that, I believe #3 works perfectly for me.

Regards,

Austin