From: Sandy King (sanking@clemson.edu)
Date: 02/17/02-03:05:27 PM Z
Just a short time ago there was a brief thread on the kallitype.
Since that time I have received a number of questions from folks on
the list about my working procedures with this process. Since I have
already jotted down the notes I am going to post them to the list for
anybody who might be interested.
But fist, a few personal observations.
Many want to compare kallitype with pt/pd. It is certainly true that
kallitypes are capable of a tonal range equal to that of pt/pd and in
fact can be made to be virtually identical with certain developers
and toning options. Ate the same time, however, it is also possible
to obtain a range of image colors not possible with platinum, and
therein lies the greatest attractiveness of the process for me.
Bear in mind that kallitype can be a very complicated or a very
simple process. Look at Dick Stevens' book if you want to see an
example of how complex it can become! I prefer to simply the process
it by working with just one or two papers, one developer and two
toning options.
Stability is also important and my choice of developer, clearing
agent and fixing procedures are designed to give the most archival
image possible. For maximum image stability all kallitypes should be
toned, as should all silver images for that matter, and especially
those consisting of brown silver. Also, avoid alkaline developers as
these make removal of the residual ferric iron more difficult.
Please note that this form of kallitype is based on ferric oxalate,
unlike Vandyke which uses ferric ammonium citrate.
Just one more note. To avoid spreading trays all over my darkroom I
do all of the processing in just one tray, with a water rinse
between each step.
Required Materials
10% silver nitrate
20% ferric oxalate (I mix from the powder)
Developer - 20% sodium citrate
Clearing Agent -3% citric acid
Fixer - 50g sodium thiosulfate, with 10g sodium carbonte plus 2g
sodium sulfite per liter.
Hypo Clear -Kodak Hypo Clear, or 1% sodium sulfite solution
Toner - Per liter, 10g of citric acid plus either 5ml of platinum #3
solution, or 25ml of 1% gold chloride (or 5ml of 5% gold chloride).
Steps
1. Mix equal parts of 10% silver nitrate plus 20% ferric oxalate for
sensitizer. I coat with a brush, a Hake or more recently the
Richeson, and use about 6ml of combined solution for a 12X20 print.
2. Coat paper and allow to air dry. This takes about 15-20 minutes.
3. Expose.
4. Develop for 6-10 minutes. The procedure is to place the print in
tray and pour the developer over the print as quickly as possible. If
you immerse the print in the developer you may get lines of uneven
development. Development is visually complete in 10-15 seconds but a
long development time is important because much of the residual
ferric iron is removed at this stage.
Contrast can be controlled by the addition of a few ml of a 5%
potassium dichromate solution the developer. I use a little as 2ml
per liter up to about 32ml per liter, which allows the use of
negatives ranging from a DR as low as 1.0 up to a maximum of about
2.2.
The developer can be reused but should be replenished. I replenish at
the rate of about 250ml of developer per 12X20 print. When
replenishing decant from the top as the bottom of the developer will
contain ferric iron, which has been cleared from the print during
development.
5. Rinse print for one minute in running water.
6. Clear with a 3% Citric Acid for 5 minutes. I use a liter for only
two prints, and then discard. Citric Acid is very inexpensive so thee
is no point in using depleted chemistry at this critical stage.
7. Rinse for one minute in running water.
8. Tone for time necessary, usually about 5 minutes. Although the
toning formula refers to mixing toner in 1-liter amounts I actually
mix it in very small amounts, tone, then discard. For example, for a
12X20 print I mix only 200ml of toning solution (2g of citric acid
plus 0.5ml of platinum #3 solution, or 2ml of 1% gold chloride and
discard after toning. You need a flat try to tone with this small
amount of toner.
The platinum toner will give a final print that is virtually
identical in color to a platinum print. The gold toner gives a very
attractive purple/brown/blue tone. With the platinum toner the
density of the print will be greater after toning than before, but
contrast will be the same. With the gold toner the contrast of the
image is increased by about a step through loss of density in the
high values, but Dmax values (shadows)
are changed little if at all.
9. Rinse in running water for one minute.
10. Fix for three minutes.
11. Rinse in running water for one minute.
12. Hypo Clear, (or 1% solution of sodium sulfite) for two minutes.
13. Rinse in running water for 20 minutes.
14. Hang to dry.
Good luck!
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