From: Sandy King (sanking@CLEMSON.EDU)
Date: 02/24/03-11:00:04 AM Z
Scott,
I saw this message earlier and thought that I had responded, but
apparently not.
Regarding the formula from Photo-Minature, I have not experimented
with the formula in the article but I doubt very much that you will
get any better results with it than with the formula given by James,
which is similar to one recommended by Dick Stevens, Russ Young,
Richard Farber, et al. There was a huge about of experimentation with
kallitype in the early part of the century but to my way of thinking
most of the formulas are simply variations that with proper working
conditions all lead to the same result.
Stevens did a lot of experimentation with additives such as gum
arabic in an attempt to keep more of the sensitizer at or near the
surface of the paper to improve apparent sharpness, but in practice
getting a smooth coating with any amount of colloid added to the
sensitizer is extremely difficult.
Experiment if you must but I seriously doubt that any of the old
formulas will give you better results than the now classic kallitype
formula based on 1 part 20% ferric oxalate and 1 part 10% silver
nitrate.
As for toning, prints toned before fixing will be richer and take on
more of the color of the toning agent than if toned after fixing. At
least that has been my experience with gold and platinum toning.
Also, toning before fixing with these agents cuts down dramatically
on bleaching of the image in the fixing bath(s).
Sandy King
>Hi all,
>
>Just read a copy of "The Kallitype Process" from the Photo-Minature
>No. 47 and had a few questions for those of you who are kallitypists.
>
>The first question is has anyone tried the formula (listed below) in
>the article? Up to this point I have been using the simple formula
>given in Christopher James' book with decent results; 1 part 20%
>Ferric Oxalate to 1 part 10% silver Nitrate. Since the article was
>written, in 1903, I would assume the quality of chemistry and paper
>has steadly increased to the point of not needing some of the
>chemicals required to obtain decent or exhibition quality prints.
>
>Part A which calls for 48 grains gum arabic, how do you convert
>grains when using liquid gum arabic?
>
>Part B calls for 1/2oz Ferric Oxalate and Potassium [K3Fe2(C204)3]
>which I assume would be Potassium Ferric Oxalate. Is that liquid or
>dry measurement? Where could I obtain it or can it be readily made
>onsite?
>
>In Part D, the article calls for the use of a 6% Potassium
>(Bi)Dichromate solution. It has always been my understanding that
>the addition of dichromate causes an increase in contrast and a
>reduction in printing speed. Most of my negatives give a slightly
>contrasty print, using the James formula, that caused the shadows to
>go slightly dark and are brought out in a pre-fix toning bath. Would
>the inclusion of the dichromate solution in sensitizer cause even
>greater contrast?
>
>I also read that for the most part, when the article was written,
>toning was done after the print had been fixed. I have always toned
>before fixing; is there any difference other than color in toning
>before the fix versus afterwards?
>
>
>Thanks for the help,
>
>Scott Wainer
><mailto:smwbmp@starpower.net>smwbmp@starpower.net
>
>***********************************************
>
>Photo-Minature No. 47 Kallitype Formula
>
>Part A
>Ferric Oxalate 1 oz
>Distilled Water 5 oz
>Gum Arabic (picked) 48 grains
>
>Part B
>Ferric Oxalate and Potassium [K3Fe2(C204)3] 1/2 oz
>Distilled Water 8
>oz
>
>Part C
>Oxalic Acid 1/2 oz
>Distilled Water 4 oz
>stronger ammonia (Ammonia Liq. 880) 100 minims
>
>Part D
>Bichromate of Potassium 120 grains
>Distilled Water 4 oz
>
>Sensitizer for average negatives
>Part A 1 oz
>Part B 1/2 oz
>Part C 30 minims
>Part D 4 drops
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