The two chemicals that are non-standard for platinum palladium printers are
the cesium and lithium chlorides are not too difficult to obtain and are not
too expensive at about $ 30.00 to $ 40.00 per ounce which will up the price
of a bottle of palladium coating solution another dollar or two.
I hesitate to mention my own firm as a source as it has never been my
intention to use the list in a commercial manner.
Be forewarned this process is still in beta test. The new salts used are no
more toxic than any of the other materials and so present no new toxicity
issues. The process works for me here in New Mexico, but for how it will
work in Key West is still unknown. Any comments are appreciated.
My thanks to Mike Ware for sharing his knowledge and comments.
Ziatype
A printing out photographic method using palladium.
beta draft
Handcoated platinum printing out papers are nothing new, Pizzighelli
describes several methods in Lietzes book "Modern Heliographic Methods" of
1888, and Mike Ware described his method in the British Journal of
Photography, Vol. 133(No 42), pp1190-1194 (17 October 1986), or 'An
Investigation of Platinum and Palladium Printing' , Journal of Photographic
Science, Vol. 34, pp13-25 1986. These methods rely on a simple system of
incorporating moisture in the emulsion and paper to facilitate developing
out of the platinum salts due to the action of the ferrous oxalate being
formed by the action of the light on the ferric oxalate. Pizzighelli's
method uses sodium ferric oxalate instead of ferric oxalate because of it
hygroscopic nature, that is it chemically absorbs moisture. Ware's method
uses ferric ammonium oxalate and ammonium chloroplatinite instead of the
usual potassium chloroplatinite in order to achieve higher solubility. As
Ware states "the photoproduct from ammonium ferric oxalate is not an
insoluble ferrous oxalate but a soluble oxalato complex of iron II, hence
the printing out effect". Tests that I've made confirm that some
hygroscopic chemical must be in the emulsion for any degree of success.
Humidifying a traditional ferric oxalate paper and printing it will result
in a stronger print out image, but it will not be strong enough to withstand
water development and will usually be quite grainy.
The Ziatype*, like the Pizzighelli and Ware methods makes use of
hygroscopic materials and ammonium ferric oxalate as key to its printing out
capability. In the Ziatype lithium chloropalladite or cesium
chloropalladite and ferric ammonium oxalate are used. As Ware has
mentioned that what is needed in the dry New Mexico climate may be quite
different from what is needed in the UK. This is probably the cause of my
unremarkable prints in tests using sodium chloropalladite and ferric
ammonium oxalate.
As I was exploring the use of other palladium chlorides in the photographic
process and came across a note that lithium chloride was perhaps the most
hygroscopic material known, and I surmised that its palladium salt would
also be similar in effect. Lithium chloropalladite is not listed in any of
the chemical references that I have searched. Since palladium makes salts
with most of the alkali metal chlorides, I calculated its formula as 1.4 gms
of lithium chloride to 2.3 gms of palladium chloride. To be on the safe side
I used 1.7 gms of lithium chloride as the extra lithium chloride should have
no deleterious effect, though any unresolved palladium chloride might.
Lithium chloride is a fairly benign chemical, and is one of the chemicals
used for treating depression. I understand that it has no effect or high for
non depressives.
The first experiments were to make prints using the standard ferric oxalate
and the lithium chloropalladite. The results were somewhat promising in that
a very strong print out image was produced but that the contrast was very
high, a great deal of graininess was produced, and the image considerably
darkened when developed in the acidified water. After several prints I
noticed that the darkening was increasing with each print. I ascribed this
to the small quantity of EDTA tetrasodium that my firm adds to its standard
ferric oxalate solution. EDTA tetrasodium has a developing effect on the
platinum print. I switched to a non EDTA ferric solution and the darkening
went away, but the prints remained grainy and contrasty.
The next step was to use ferric ammonium oxalate instead of ferric oxalate.
The print out image was quite strong and no darkening was observed during
development. The print however was quite flat and lacked contrast however
this was to be expected as this negative was too flat and really unsuitable
for even regular platinum printing without a boost in contrast. I then made
up a solution of ferric ammonium oxalate with .33 gms of potassium chlorate
and in the manner of traditional platinum printing mixed a portion of each.
The first print I made used a 50-50 mix of solutions Nos. 1 and 2 and the
contrast was perfect for the negative I used. An added plus of perhaps for
some a minus is that the prints produced are neutral black with no hint of
brown with a dead slate gray in the mid tones.
Knowing that some printers at some time or another will prefer a brown tone
to their print. In my explorations I had made some standard prints with
cesium chloropalladite and had noticed that they were considerably warmer in
tone than the other palladium salts I had experimented with. I had also seen
a note that cesium chloride was also a highly hygroscopic material so I made
a Ziatype print using the cesium salt instead of the lithium. It produced a
very soft warm print. The cesium version is very soft and lacks a strong
dMax and appears to be unsuitable for general purpose work by itself. It,
however, could be used to make delicate soft high key images.
The obvious next step was to mix the lithium and the cesium to adjust the
warmth of the print. A properly made Ziatype made with only the lithium salt
should be cold neutral black, though if some drying occurs, there may be
some detectable warmth in the highlight densities. To impart some warmth to
the print reduce the lithium salt and replace it with the cesium. The effect
of the cesium can be quite radical as just one drop in a total of 10 of the
metal salt can warm up the print.
The Ziatype process:
The chemicals:
Sol.. No 1 10 gms of ferric ammonium oxalate
25 mls water
Sol. No. 2A 10 gms of ferric ammonium oxalate
.33 gms potassium chlorate
25 mls water
Lithium chloropalladite
Sol. No. 3a 2.3 gms palladium chloride
1.7 gms lithium chloride
25 mls. Water
Cesium Chloropalladite
Sol. No. 3a 2.3 gms palladium chloride
2.3 gms cesium chloride
25 mls water
Developer/clear 80 mls hydrochloric acid
1000 mls water
The Procedure
The ratio of the coating solutions is the same as in normal palladium
printing, that is total ammonium ferric solution will equal total lithium
chloropalladite. Vary the portion of No 1 and No 2 to get the contrast
level needed, that is more No 1 for lower contrast prints, more No 2 for
higher contrast prints. The Ziatype process will handle a print with all No
2 with no visible increase in graininess. I believe Ware also notes this
for his process.
To control the warmth of the image vary the ratio of Solution No 3 adding
more of the cesium salt for more warmth.
For a 5 x 7 print with a mid level of contrast a good starting point would
be 4 drops of Solution No 1, 4 drops of Solution No 2 and 8 drops of
Solution No 3. Note that the total of Nos. 1 and 2 should equal the No 3.
Coat as you normally would for any platinum or palladium print, I prefer a
coating rod. for small prints.
Dry with a hairdryer or in a manner that you've become accustomed.
Humidify the paper. For tests I've been using a cheap Sunbeam steam
humidifier purchased at a drugstore for about $15.00. I hold the print over
the spout with the emulsion side facing the spout and move the print around
to get the steam evenly over the emulsion. I've not been real careful and
the results have been good. The emulsion seems to really grab the moisture.
I do this on a 5 x 7 print for about 1 minute. For large prints I suspect a
humidity chamber made of a box and a humidifier would work better.
Print either in the sun or with a light source. Within a minute or two in
the sun or several minutes in a light source you will see the margins
darken. In a few minutes more the margins will darken to a dark purple
black. I standard print frame is recommended as you may after a few minutes
check the print. When the print appears as full and complete you are
finished printing. It will look pretty much as it will when cleared, a
little experience will be needed to get the precise exposure.
Quickly immerse the print in the developer / clearing agent. Leave for about
30 seconds and transfer to a tray of water until cleared of all yellow
highlights. Wash in another tray for 5 minutes.
Blot and complete drying on a screen.
Sell prints for money or share with friends
Notes:
I've been using Cranes platinotype paper with good results. Unfortunately
Platine has given poor results, the prints lacking in dMax.
The process has been highly predictable.
Ferric sodium oxalate should work and may well produce warmer images, I need
to prepare a batch and try it.
Constant inspection of the image by opening the back seems to have on
occasion dried out the emulsion and causing problems. These tests were done
in Santa Fe New Mexico where the humidity was running in the 20 percent
range. If it works here it should work most anywhere.
* Named for the ancient Anasazi symbol for the sun, familiar as the
circular image with 4 sets of 4 rays, seen on the New Mexico flag and
license plates. It seemed appropriate as we just moved to New Mexico and I
have been using its sun to make the prints.
Dick Sullivan
Bostick & Sullivan
Santa Fe, New mexico