After a few days ziatype testingÂ I’m feeling kind of crazy — printing the tiny gray patches over and over again… but I keep saying to myself it’s not wasted time, I’m learning all the time about this process and its chemistry. I had to try the different chemicals and their mixtures to find out their effects on the images. After this testing I’m supposed to be readyÂ to choose the suitable ziatype method for any particular image.
ChartThrob test prints on my desk.
But, before proceeding to printing real photographs, I wanted to make more tests on the paper humidity. Definitely my first tests were printed on too damp paper (see the previous posts). I know the humidity is part of the process, but I wanted to see what will happen when the sensitized paper is fully dried.
So, I coated a piece of Guarro paper, let the sensitizer soak in for a few minutes, and force dried the paper with a hair dryer, with the cool setting. On my exposure unit I can watch (through a yellow safelight window) the forming of the printing-out image. It seems that when the paper has proper humidity the image prints out even and steady, but if the paper is too dry the printing-out image comes out grainy and blotchy — that’s exactly what happed here with the dry paper.
Exposing a dry ziatype paper. The printing-out image appears grainy and uneven. (Picture taken through the yellow safety window of the exposure unit)
The print exposed dry, just before going to the clearing bath.
After processing the print doesn’t look so blotchy any more, but the maximum density is not very high.
OK, I’m beginning to learn the differences between dry and humid papers, and, more importantly, learning to dry my papers just right, so that they are a bit moist but dry enough to be safely contacted with the negative (I don’t use the acetate mylar between the paper and negative any more). On the tests below my typical drying procedure was to let the coated paper sit for awhile (until the wet shiny surface turned to matte), and then blow dry it with a hair dryer (the coated side only, dryer set to cool) for 3 – 5 minutes. The relative humidity in my working area ranges between 60 and 75 % at this time of year.
With the ziatype it should be possible to acquire remarkable variations in color, from very warm reddish brown to cool blue and greenish blue hues. I’ve done my gray-patch printing on several different papers and noticed that papers can have their effects on the print color too. But mainly the color changes are made with chemistry mixtures. So, more chemicals are needed; such as gold, cesium and tungstate.
More chemicals to the setting.
On the grounds of the previous tests it looked like something was wrong with my process; ziatype should naturally be a long scale process, meaning that from a normal negative targeted for modern photo papers I am supposed to get a low contrast print. However, my results looked quite high in contrast. So, I’m wondering what could be the issue here. It shouldn’t be the paper, I have tried many types already and the results look similar. To find out if it is the chemistry, I made more test prints.
In the very basic ziatype process there are only two sensitizing solutions: the ammonium ferric oxalate (afo) which is the light sensitive compound, and lithium palladium chloride (LiPd) for making the metallic palladium. The chemicals are easily mixed to distilled water, and there really should not be much that could go wrong here.
Anyway, I started experimenting by diluting the two solutios differently with water. The idea of this was to examine if there really is something spoiled or badly mixed in my chemistry, and try to find out about the effects produced by changing the chemistry proportions. For these tests I also changed my paper to Somerset, because I now have a feeling it is somewhatÂ easier to coat and dry to the specific humidity. Here is a quick review of the results.
1) Solution #1 has been diluted by substituting water for half of it. I don’t see any dramatic changes; the Dmax is a bit lower and the print tone warmer. Lowering the contrast with diluting solutions doesn’t seem to work — well, maybe a little bit — 11 – 12 steps are readable from the Stouffer 21-step tablet, instead of the 9 – 10 steps of the full strength chemistry.
2) Here the palladium part of the chemistry has been half diluted with water, the afo solution unaltered. Dmax is definitely lower, the print is uneven all over, with weak Dmax.
3) Here’s another try from the #1 dilution. This time I encreased the exposure by 50%. A very nice Dmax, and the longest scale that I have got so far — 12 discernible steps on the Stouffer. Think I will stick to this paper / chemistry combination for a while.
Finally, before starting to print photographs instead of boring gray chart tests, I wanted to try the different mixes of the chemistry, just to get an idea of the colors that ziatype can introduce. The correction curve has been created for the basic Afo + LiPd mixture only, so except for the first test, the ChartThrob tonalities are way off from optimum here. Each mix of sensitizer will need a correction curve of its own…
1) Somerset paper, ChartThrob negative (with a correction curve) printed with an Epson 1800. After several tests I ended up to make my basic zia mixture: Afo solution 3 parts + water 1 part + LiPd 4 parts. I don’t add the Tween surfactant any more.
2) When aiming for a little warmer print tones, cesium palladium solution can be added to LiPd: Afo solution 3 parts + water 1 part + LiPd 2 parts + CePd 2 parts.
3) By adding gold to the sensitizer the print highlights take a cold bluish tone, while the shadows don’t change much: Afo solution 3 parts + water 1 part + LiPd 2 parts + gold chloride (5% sol.) 2 parts.
4) A little bit of tungstate added will also warm the print (not as brown as #2) and lower the contrast: Afo solution 3 parts + water 1 part + LiPd 4 parts + sodium tungstate (40% sol.) 1 part.
5) My “Gold Extra”, more gold added, results to more prominent split tones: Afo solution 5 parts + water 1 part + LiPd 2 parts + gold chloride (5% sol.) 4 parts.
6) According to Sullivan and Weese (The New Platinum Print) gold and tungstate together mixed in the sensitizer will produce green tones: Afo solution 3 parts + water 1 part + LiPd 3 parts + gold chloride (5% sol.) 1 part + sodium tungstate (30% sol.) 1 part.
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