From: pete (temperaprint@blueyonder.co.uk)
Date: 02/01/02-08:50:07 AM Z
Anderson again two
So Ietıs return to this pigment test and find out where the main bone of
contention seems to lie. Judy Seigel believes if I have it correct. That
Paul Anderson was mistaken in the initial paragraph of his published pigment
staining test because he was practising her [seems logical theorem] and not
actually doing the test only proposing it as a possible method of
measurement.
Quoted in the following passage: --
>>Coating Mixture As the longest scale of gradation is accrued when the coating
mixture contains the largest amount of pigment and as a long scale is
usually desired, it follows that the coating mixture should hold as much of
the pigment as can satisfactorily be used. <<
In my opinion this opening paragraph of Paulıs is where the main
misunderstanding stems. We have to realise that Paul was talking from the
viewpoint of the turn of the nineteenth century, when no Stouffer wedges
existed.
Sensitomertry was just in is its cradle, and there was one hell of row going
on in the photographic establishment of that time, between Ferdinand Hurter
and Vero C Driffield and Capt. Capstaff as to whether to accept
Sensitomertry or no.
Terms and concepts that we use and understand today such, as D/max, tonal
range and contrast, subject/brightness range, the difference between
reflection density and transmitted density, D-logE- curves, gamma, etc were
not in use then. It was as yet an untried language of measurement.
The words Paul was actually using had a slightly different meaning to what
is understood today, but what he was trying to say still has relevance, he
was defining the D/max or maximum black of the print in relationship to the
first appearance of pigment stain. A criteria which I personally find still
acceptable at the turn of this last Century.
In my opinion where Judy has got it wrong is to confuse D/max or maximum
black with tonal contrast rendition!
Judy goes on to say: --
>>Business: Anderson says (as I recall, in his own book, but picked up AND
Elaborated in Schaefer's "Ansel Adams Guide 2"), that the more pigment in
A given mix, the more tones you get, because, more pigment particles will
Make more layers of density. <<
He does not say that at all, what he actually said was ---:
As the longest scale of gradation is accrued when the coating mixture
contains the largest amount of pigment and as a long scale is usually
desired,
He is in fact talking about D/max or maximum black, the tonal scale is being
defined, not how many tones or layers of density you can see! This is a
totally different issue.
Judy is quite correct, when she says that in a total dichromate colloid
pigment mix. As the amount of pigment increases the contrast gets steeper,
this confirms my own experimentation with egg dichromate in fact using this
system I have achieved a lith like print from a Stouffer wedge.
However a total mix is not the Anderson test, if we wish to talk about a
total mix then a lot of other parameters have to be included, such as the
true nature of the total print image. Factors such as internal and external
sizing, dichromate stain, the texture of the paper surface, humidity and
ambient temperature. All would have to be taken into consideration
It is doubtful if such a test in practical terms, would be feasible
Also the example quoted from her excellent magazine p. 46 of P-F #2. Is
important, as it shows up the basic misunderstanding of the difference
between tonal contrast and tonal scale i.e. D/max.
I will try to explain this more clearly. Judy could get a very similar
results to her tests if she exposed and developed a piece of normal
photographic paper too a Stouffer wedge on grade 0 contrast paper then on
grade 4 or 5. Although the number of tones would be different in each
example shown. The tonal scale D/max normally 1.8 reflection density would
be the same.
So if my premise is correct the rest of the Anderson article is very
straightforward. It is a simple test to show the effect of pigment stain on
a sheet of watercolour paper. It is the paper that is the real villain.
Not the gum-pigment/ratio
It is the paper that stains not the pigment, and to say as Judy does --:
>>I think non-gummiest reading this thread might get the idea that stain is
The ever present monster in gum printing... I haven't found it so, tho the
Tests seem to have become a bone of contention (in the service of, seems
To me not beyond the realm of possibility, another agenda). <<
Judy has herself made these tests a bone of contention, by constantly
beating David Scopick and others over the head with them for years and
years.
Incidentally I do not have any other agenda; my interests lie with potions
and pictures not people and politics. I have too much respect for the
massive contribution Judy has made to photo /alt over the years. Iım sure
she would admit to being wrong if she felt she was, obviously in this case
she does not. Her PFP magazines are one of my more treasured possessions.
It is on this single particular test issue, that I am convinced that she is
wrong. I have taught dichromate colloid processes such as Casein Egg,
Gelatine Gum/Gloy, PVA, during the past thirty years. And found that once
the physical structure of the colloid is understood. The main problems have
always been associated with the nature of the substrate not the colloid. In
the case of Gum it has been the watercolour paper itself that can be
troublesome.
Watercolour Paper is specifically made to stain by the Manufacturer.
Watercolour painting is a process of very delicate pigment staining.
The paint just clings onto the surface of the paper, by the skin of its
teeth
A good paper has been structured and sized to hold onto those precious
grains of pigment with tenacity. Watercolour paper was not designed for Gum
printing, quite the reverse. David Scopick recommends etching paper instead
of watercolour for similar reasons, however we still have problems with
etching paper. It would be nice for a papermaker to design a specialist
paper just for Dichromate Colloid prints making. Paper also has a very
elastic nature and therefore humidity is a constant problem in terms of
registration.
And if we continue to accept my contention that pigment stain in the
structure of the paper is a real concern, then the Andersonıs test has even
more relevance.
Pigments stain is rather like fire you can cook your dinner or burn your
house down with it. I accept that the skilled printer can surmount these
problems, indeed one has only to look at the masterly work of Katharine
Thayer, Stephen Livick, David Scopick, Joe Smigiel, and many otherıs to see
what can be accomplished.
However I do maintain that the Anderson/Henney&Dudley/Crawford/Scopick
pigment test gets the newbee into the ballpark. However once in said,
ballpark, then there is another game to play.
-- http://www.books.i12.com/parlour/index.html
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