Digital BW, The Print

Austin,

I am afraid that I just don't see any point in answering you in detail on
the items below. The trains of thought become so fractured that they lose
all meaning. 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.

In general I have nothing new to add. 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.

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.

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.

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. I want to stress again to you and to everyone else that
subtracting two log values such as density is an expression of the ratio
between the two properties. This is in complete agreement with the common
definition of dynamic range. I put it to you that the burden is upon you to
show that the more detailed equation of DyR is more applicable and the
burden is not on everyone else to defend a long accepted practice.

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
outside of a purely digital image as in a scan file. An actual print either
appears to have a continuous, unbroken change from tone to tone or it looks
posterized and inferior in quality. There seems to be very little latitude
at this threshold.

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.

Martin


----- Original Message -----
From: "Austin Franklin" <darkroom@...>
To: <DigitalBlackandWhiteThePrint@yahoogroups.com>
Sent: Wednesday, April 03, 2002 1:07 PM
Subject: RE: [Digital BW] Thoughts about Imaging


> > > > The idea of distinguishing between tones and the number of tones are
> > > > concepts that I do not ever recall hearing in discussions of
> > traditional
> > > > photography. If not new concepts, they seem to be new to the
> > discussion
> > of
> > > > photography. I believe that they were not discussed in traditional
> > > > photography because they simply were of no interest.
> >
> > >
> > > That's just so untrue.
> >
> > I don't recall that you were in any of the discussions I was in
> > or know what
> > books I read, so how would you know?
>
> Because you weren't there, doesn't mean it wasn't discussed.
>
> > If
> > you have something different, then site me a reference.
>
> I defer to Todd for that ;-)
>
> > >  I believe it wasn't discussed by "pedestrians",
> >
> > Yes we are all pedestrians here plodding along trying to make the best
> > prints we can from our images. If it is so important, then why did in
not
> > find its way into pedestrian discussions and magazine articles?
>
> Pedestrians don't care about MTF and a host of other very technical
analysis
> issues, that are VERY important (to some people) to the final image.
>
> > > and
> > > given communications as it was until the Internet, there really wasn't
a
> > > "general" place TO discuss it.
> >
> > First you chastise me
>
> I did not chastise you at all.  I merely stated that we seem to forget the
> role that the Internet has played on "information" (right and wrong
> information) availability, as well as given us places to discuss this on a
> daily/hourly basis.
>
> > ...and now you
> > tell me there could not have been a broad discussion until we had the
> > Internet!
>
> That is just not what I said at all.  Of course there were discussions,
just
> not as "accessible" as today.
>
> > Lots of books have been written on the subject and I have looked over
the
> > few I have, and can find no reference to DyR.
>
> And that means it doesn't exist?  They didn't discuss film grain
> molecularity, did they?
>
> > > with other photography teachers (yes, I taught photography in the mid
> > > 70's), students and professionals.  Now that doesn't mean they
actually
> > > understood it as dynamic range...
> >
> > Or did they simply not agree?
>
> ...they just didn't necessarily call "it" dynamic range.  They may have
> called it number of tones or tonality or whatever.
>
> > You seem to equate not agreeing with you to
> > not understanding you.
>
> Not at all.  Just because someone understood a concept and didn't give a
> particular name to that concept/property doesn't have anything to do with
> agreement.
>
> > > but whether you assign a technical name to
> > > a concept or not, the concept still exists, as well as has been
> > discussed
> > > for a LONG time.
> >
> > Fine. Now site me some photographic references to support that DyR, as
you
> > use it, was a concept in wide or even narrow use in the making of
> > photographs.
>
> I am curious why that matters at all, except as yet another off the real
> subject ancillary argument.  If no one discussed it, does it mean that it
> didn't exist?  Anyway, AA obviously used the term in "The Negative".
Again,
> I defer to Todd on providing references.
>
> > > I hear photographers talking about the difference between the tonal
> > > gradations of Plus-X and Tri-X somewhat frequently...and how
> > Plus-X looks
> > > "flat" compared to Tri-X...  It isn't density range (as that is
> > defined by
> > > the printing "system), and it isn't tonal "mapping" that causes this
(as
> > > that can be re-mapped any way you want)...
> >
> > Those seem like pretty pedestrian descriptions to me. I guess pedestrian
> > descriptions are okay when they support your argument and
> > inadmissible when
> > they don't. Give me a break.
>
> If the description uses ambiguous terms, then they need to be
> qualified...and any definition, pedestrian or technical can use ambiguous
> terms.  It's just that pedestrian definitions of very technical issues
tend
> to be incomplete, and technical definitions aren't.  I prefer definitions
> that are unambiguous and are complete.  I don't care whether they "seem"
> pedestrian or not.
>
> > Sounds like they were talking about the gamma of the two films.
>
> tonal mapping is gamma, not density range, and not the "number" of tonal
> gradations.
>
> > Besides if
> > their Plus-X negs looked flat perhaps they didn't develop them properly.
I
> > took a lot of wonder 35mm Plus-X negs and I personally found that
> > the tonal
> > renditions in prints to be much nicer than Tri-X.
>
> Absolutely, but that doesn't mean that to some people, more/better
> gradations as in less contrast don't look flat.
>
> > By your
> > definition it [Plus-X] had
> > a better DyR since if you take granularity as noise then Plus-X would
have
> > the higher DyR than Tri-X.
>
> Grain is a contributing factor to dynamic range ;-)
>
> > > I am amazed at how much energy is being put into "fighting" the
> > concept of
> > > dynamic range.  It reminds me of "bokeh" discussions...
> >
> > Absolutely no one is fighting the concept of dynamic range,
>
> Claiming it is EXACTLY the same thing as DENSITY RANGE, IS fighting it.
>
> > Austin. Some of
> > us are resisting your attempts to apply an equation to photographic
prints
> > for which you cannot provide a value or a clear description for
> > the key term
> > noise.
>
> If it doesn't have a FIXED value, then it doesn't exist?  BTW, I HAVE
> provided a VERY CLEAR description for the key term "smallest discernable
> signal", which may or may not be noise.  You just don't like my answer!
> And, because my description may or may not be inadequate, or you may or
may
> not like/understand it, doesn't mean dynamic range isn't a property of
film
> and prints.  It is, and it doesn't have to be measured to exist.
>
> > A term that seems to have a high probability of being
> > insignificant.
>
> Perhaps to you!  I am sure for some people, it is insignificant, but for
my
> work it is VERY significant, and it shows in my images.  And it is NOT
> DENSITY range, it is DYNAMIC range.
>
> > It is just that what you have explained does not appear to be
> > useful in this
> > particular case.
>
> To you.
>
> > You have not demonstrated that
> > DyR=10log{(Dmax-Dmin)/noise}
> > of a print medium tells us anything helpful about making prints.
>
> It is not necessary to "run" the equation and come up with an exact number
> to understand the concept (and for it to exist), and have it apply to your
> work, that is if your work warrants it.  Tonality IS important, very
> important to some, and it is NOT described by density range.
>
> Austin
>
>
>
> Please visit the Group Homepage to check the Files, Bookmarks, Polls and
other resources as they are often being updated. The page is at:
>
> http://groups.yahoo.com/group/DigitalBlackandWhiteThePrint
>
> Please follow these basic guidelines:
> - Include your full name with your message.
> - Include the address of your website, if you have one.
> - As threads develop, trim off excess portions of earlier messages to keep
them short.
> - As the topic of a thread changes remember to change the subject header.
> - Good manners are required at all time. No personal attacks or "flames."
> - Complete your Yahoo profile.
> - Before posting a question, search the message archives and the various
resources on the homepage.
>
>
>
>
> Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
>
>
>