From: Sandy King (sanking@clemson.edu)
Date: 08/16/02-01:15:54 PM Z
Permanence of Kallitype Prints
For some time now I have been making gold, platinum and palladium
toned kalllitypes (ferric oxalate version), and posted working
procedures on my method to the list earlier this year. People who
have seen my prints have been impressed with the deep, rich shadows,
clear highlights, and a wide tonal range. With platinum and
palladium toning I have recently begun to get the same kind of
results with the simpler Van Dyke (ferric ammonium citrate) version
of the kallitype. The platinum and palladium toned prints are
identical in color and tonal range to pt/pd prints and print with
about the same speed. In fact, since toning substitutes one metal for
the other, platinum and palladium replacing silver in this instance,
there is every reason to believe that this kind of kallitype is in
fact a platinum or palladium, with the same degree of permanence.
I recall that a Portuguese photographer, Carlos Gasparino if memory
serves me well, once stated that he had placed some toned kallitype
prints in his care and drove around with them for a year or so and
saw no change. However, I would like to be sure on the question of
permanence so since I have been doing quite a bit of printing with
toned kallitype I have decided to run a similar, but more detailed
test than the one reported by Mr. Gasparino.
What I have done is this. Using a Stouffer 4X5 step wedge I made ten
kallitype prints, five Van Dykes and five traditional kallitype
prints (ferric oxalate). The five Van Dykes were finished as follows.
#1 No toning
#2 Platinum toned
#3 Palladium toned
#4 Platinum and Palladium, equal amounts, toned
#5 Gold toned
The three traditional kallitypes were finished as below.
#6 No toning
#7 Platinum toned
#8 Palladium toned
#9 Platinum and Palladium toned, equal amounts
#10 Gold toned
All of the prints were processed for maximum archival qualities,
which included two separate fixing baths, separated by a wash, and
the use of a hypo clearing agent, in this case a 1% solution of
sodium sulfite. Prints were washed for 30 minutes following the
hypo-clearing bath.
I have now read and recorded the densities of each of these prints
with a reflection densitometer, and mounted them on a piece of
archival mat board with pushpins. What I propose to do is now place
the mat board with the prints in my car and leave them there for a
year, rotating the board every week. I am going to place the board in
the area of the car where it will receive both direct and indirect
sunlight every day. At three months I will read the densities again
and note any changes, dot he same again at six months, and again at
the end of one year.
I believe that the results of this test should answer some important
question about the permanence of kallitype prints, in general, and
the permanence of traditional kallitypes as opposed to Van Dyke
prints in particular. It should also indicate the archival
importance of toning with the metals tested.
Any comments or suggestions regarding this test would be appreciated.
Sandy King
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