The New Cyanotype Continued

New Cyanotype PrintIt’s early morning and still dark out. I’m heating up distilled water to prepare the single bottle emulsion for the New Cyanotype process.

What if you were able to print cyanotypes with the tonal range of palladium, and its detail, and have it clear with the ease of a platinum print with little loss of image substance? This seems to be what the Mike Ware’s process gives you!

During the preparation of his book Cyanotype: The history, science and art of photographic printing in Prussian Blue, Mike Ware looked closely at existing variations on the cyanotype process which were all related to John Herschel’s original formulation. He created a new formula with a new sensitizer. The chemicals used to create the sensitizer are (from Mike Ware’s site):

Ammonium Iron(III) Oxalate 30 g
Potassium Ferricyanide 10 g
Ammonium Dichromate 0.1 g
Distilled water to make 100 cc

Detailed instructions for the New Cyanotype Process are found on Mike Ware’s web site. Ammonium Iron(III) Oxalate in the formula is equivalent to Ferric Ammonium Oxalate (also called Ferric Ammonium Oxalate Trihydrate). This chemical is a bit more hazardous than the sensitizer Ferric Ammonium Citrate used in the classic process defined by Herschel, the latter being used as a food additive. The Ammonium Iron Oxalate is more readily absorbed into the paper, embeds itself in the paper fiber instead of sitting on the surface of the paper (where it is later washed off during clearing). It is certainly less hazardous than many other chemicals you can run across in your dim room.

Which brings me to the Ammonium Dichromate in the formula. Hazardous stuff. Let me help you out here. I wear a 3M 7500 series respirator when working with hazardous dusts, including ferric oxalate in the sensitizer for platinum emulsion. I have ordered organic vapor cartridges for my work with solvents I’m using in cleaning up polymer plates (though I’m using the safest things possible).

The preparation of the sensitizer requires heating the solution. I used a hot water bath on a Corning magnetic stirrer/warmer plate (a slight indulgence that simplifies greatly making ferric oxalate sensitizer for platinum printing). Mike Ware recommends temperatures for dissolving the chemicals separately, but he says they are not critical, and the components quickly dissolve. The hot solutions are combined and allowed to cool overnight in the dark. The solution is filtered (I pour it carefully leaving the precipitated crystals behind) using a coffee filter, and poured into a dark brown dropper bottle after topping off to 100ml. What could be simpler?

I wrote up my first impressions on the New Cyanotype process before. Long tonal scale, fast exposure time of 2m 20s. Easily cleared in slightly acidified wash (my tap water is alkaline which is to be avoided in processing cyanotypes). I am able to play a stream of water to help clear the unexposed sensitizer lightly over the image. I hang dry, then press flat in my hot press.

The single bottle emulsion, not subject to mold formation of the original formula, is a breeze to use. No mixing, simply coat and go.

My paper of choice for New Cyanotype is Weston Diploma. John Zokowski, paper merchant extraordinaire, resurrected this paper for fine art photography use. Thin, good wet strength, very smooth surface that holds a lot of detail. The paper absolutely requires one drop of 40% citric acid per ml of sensitizer to eliminate chemical fogging. This is described on Mike Ware’s site in his practical instructions. I use a glass rod to coat the paper. You can find some instructions on rod coating here.  If you’re lucky, you can access the section of Mike Ware’s Cyanotype Book on rod coating through Google Books link. The paper once coated should not sit for more than a couple hours after coating – as it will fog seemingly from the surrounding paper chemistry. Once the paper is coated, I keep it and other coated papers in a dark box just to be on the safe side until used. I use a hair dryer on low heat to consistently dry the paper immediately prior to exposure.

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