The ziatype process

An extract from Christina Z. Anderson’s book Alternative Processes Condensed (this book is now replaced by Gum Printing and Other Amazing Contact Printing Processes), which includes a lot more information on several alternative processes.

Always be careful when handling chemicals. Read the health and safety instructions.

Writer / Christina Z. Anderson
Photographer / Carl Weese

Ziatype print: Kitchen Window by Carl Weese.
Ziatype print: Kitchen Window by Carl Weese.

The ziatype is a variation of the Pizzighelli POP process that uses lithium palladium chloride (lithium chloropallidite) as the primary metal and ammonium ferric oxalate for the iron compound to produce a continuous tone print. Color and contrast are controlled chemically, unlike other Pizzighelli processes where color and contrast are controlled by humidity. The ziatype was originated by Richard Sullivan of Bostick and Sullivan and tested to perfection by Carl Weese.
The ziatype prints out a full image instead of developing it out (it is POP not DOP), so you see what you get after exposing, pretty much. It has a greater range of contrast than pt/pd prints without increased graininess; you can print normal silver negatives that require grade 2 or even 3 paper.

Ziatype has good Dmax without using platinum. It is about 20-40% faster than developing out methods.

There are a greater range of color choices — browns, red browns, purples and grays. Also, wet processing is much simpler: no developer is needed, just a water wash, clear, and a final wash.

Ziatype is not as finicky with papers.

I thank Carl Weese, for most of this information came from his article: Ziatype: A Brand New 19th Century Process, Photo Techniques Magazine, July/August 1997, pp. 19-28. Carl also was kind enough to proofread this chapter and make corrections! Other articles on ziatype can be found on the Bostick and Sullivan website, and you can purchase his and Sullivan’s book, The New Platinum Print for further information, if ziatype becomes your process of choice.


Original Formula:

Solution 1:
ferric ammonium oxalate 10 g
water 25 ml

Solution 2:
ferric ammonium oxalate 10 g
potassium chlorate 0.9 g
water 25 ml

Solution 3:
palladium chloride 2.3 g
lithium chloride 1.7 g
water 25 ml

Mike at is one source of chemicals. And you can order a kit from Bostick and Sullivan.

Papers to Use

Ziatype is not as paper sensitive so try all kinds. To be safe, use any that work well with platinum/palladium.


As little as 24 drops coats an 8×10 on Arches Platine or Cranes Cover, both low-absorbency papers. Otherwise 32 drops is about correct. More absorbent papers such as Stonehenge will require 25% more.

Ziatype, according to Carl Weese, gives the best results when coated thinly.

With developing out processes, more solution increases print quality, but with ziatype, a printing out process, less solution is better.

This is easiest to do with a glass rod, or the latest tool of choice–the Richeson Magic Brush. It is the brush of choice for many ziatypists, pt/pd printers, etc.. Its bristles absorb so little fluid that the savings of expensive chemistry will pay for the brush in no time flat. You can get the brush at many art stores. The 4-inch Richeson 9010 is about $70, but there are also 1/2″ and 1″ sizes on up. Use a brush size as little as 1/10 the largest negative dimension.

Coat under a yellow bug light or 60 watt tungsten–no fluorescents. It will fog under more light.

Mark the area on the paper you want to coat. Write on the margin all the info pertaining to that print so you don’t forget it.

Use drops: the number of combined drops of solution 1 and 2 always equals solution 3, just like it does in pt/pd.

You also have the option of adding drops of other solutions into the mix. Check the Contrast Controls section and chart further on at the end of this article.

Coat the paper and let it dry for a short while until the surface goes matte. Then blow dry with cool air the coated side only. This will keep a bit of moisture in the layer. As soon as the surface is dry, expose your paper. This drying time varies with the rH of your room–it may be as short as 30 seconds in a dry climate, on up to a couple minutes in a humid climate. The paper should feel limp, not crisp.

If for some reason it gets crisp, then you will have to rehumidify it, or else you will have a pale brown print. One way is to hold it over a pan of just boiled water for 30-60 seconds, or better yet, buy an inexpensive ultrasonic humidifier and steam it for about a minute in the stream of cool moisture. How much to humidify depends on the humidity of the environment you are working in, of course. Having a humidity gauge has been invaluable in my darkroom. I think I paid $30 for it at Brookstone, and in Montana where the humidity averages 20% in the winter, it is necessary for me to keep tabs on whether or not I need to turn on the humidifier.

The no-humidify process produces colder toned, less contrasty prints than the warmer toned, more contrasty humidify way.

You could even not humidify and develop the ziatype out just as you do a pt/pd print, but this probably defeats the purpose of the ease in ziatype’s processing procedure. This produces sepia tones.


When ready to expose, if you are at all worrried about moisture ruining your negative, layer the paper with a 1 to 3 mil (.0005 thickness) Mylar or acetate sheet in between the negative and paper and another one on top of the paper in the contact frame. This keeps the moisture in the paper during exposure and protects your negative from getting ruined.

Once you get proficient with determining when your paper is dry enough but still retains enough moisture, dispense with the headache of both of these plastic sheets and attendant dust issues.

A couple minutes in bright sunlight will be good for an average negative. Pyro negs take 5 or 6. Shade is a stop slower. The print will appear yellow in the highlights but look normal everywhere else.


Immerse your print in running water for 5 minutes, or the equivalent of changing the water twice a minute during that time.

Ziatype print. Floodwaters by Carl Weese.
Ziatype print. Floodwaters by Carl Weese.

Then clear the print in a Kodak hypoclear bath, or any of the clearing baths used with pt/pd printing such as EDTA. Weese recommends a soak in a citric acid bath (1 T. to 1 liter warm water) for 10 minutes followed by an EDTA/sulfite bath for another 10 minutes (1 T. each per liter). The clearing bath removes any traces of iron sensitizer left in the paper. Make sure there are no remaining traces of yellow in the print.

Then wash for 10 minutes and dry. That’s it!

Contrast and Color Controls

Now, if you want to get more complex, you can use different chemicals in the sensitizing mix. If you are going to do these more complex mixtures, consult the chart, below, but I recommend you also buy Sullivan and Weese’s book The New Platinum Print, available on the Bostick and Sullivan website. Buy these extra chemicals from them, too.

For example, you can substitute some gold chloride 5% or cesium palladium in place of the #3. You cannot use both gold and cesium palladium in the same mix.

Gold will give you cooler color, grays, blues, and purple tones, but printing times will lengthen and contrast will increase. At 15-25% the color of the midtones cools, and Dmax raises and so does the highlight contrast. Shadows do not gain contrast. At 50% you get more blue tones. At 80% you get the lavender colors. You substitute the gold chloride for the lithium palladium chloride, drop for drop. Carl Weese likes 80% LiPd and 20% gold.

Cesium palladium can be used in place of #3, too. It will give you warmer and more contrasty prints. At 50/50 you will have neutral black shadows and warmer midtones and highlights. Carl Weese likes 75% LiPd and 25% CsPd with dichromate added.

CsPd must be used hot, though, as it precipitates out at room temp, so you have to have a method of heating during use, such as a coffee warmer hot plate. You can even go on up to a total cesium palladium mix. That will be very warm and have red tones in the darkest areas.

You can add drops of a 5% ammonium dichromate to the sensitizer to increase contrast. One drop of this will be plenty for an 8×10. You never use this in conjunction with Solution no. 2, but in place of it. Hence, you’d use equal Solution no. 1 and 3, and add the drop or more of ammonium dichromate as you see fit.

For instance, if you have a negative that looks like it is best on a grade 2 or 3 paper, use 12 drops of #1, 12 of #3, and 1 drop of the 5% ammonium dichromate to do an 8×10. It increases printing times and decreases the self masking of the process, and also is warmer than using the #2 solution to mess with contrast.

Weese only uses ammonium dichromate for contrast, thinking it much superior to using the B solution potassium chlorate. However, he adds that the best prints are made from no contrast agent at all.

Sodium tungstate warms the print and lowers the contrast. Use drops of this from the 40% solution Bostick and Sullivan sells.

50% lithium palladium, 25% gold chloride, and 25% sodium tungstate may produce blue/black split tones.

A print will be neutral gray unless left to sit after exposure without clearing. Then it will be browner.

afo LiPd CsPd Gold am di tung color contrast
12 12         neutral black low
12   12       warm low
12 12     2%   neutral low/medium
12 12     5%   warm medium
12 12     20%   warmer high
12 10   2     cool medium
12 8   4     very cool high
12 4   8     purple very high
12 9   3   2 green low
            blue medium
12 12       2 slightly warm low
12 12       3 very warm very low
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