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jp
29-Aug-2013, 07:41
You can talk about curves and density numbers all day, but this shows how pyro stained negatives behave different in UV versus visual light.

Playing with my new UV blacklight box for exposing cyanotypes.

Here is a fp4+ negative developed in 1:1:100 pyrocat hd (developer down the drain; no restaining) and a standard stouffer step wedge, which is probably not processed with a staining developer.

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Here is the resulting print. single coated arches platine, B&S chem. I'll be bleaching and tea toning it tonight, that's why the highlights are still a little dark; I'm expecting to lose a little highlight detail in that process.

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On the negative, the step wedge tones range from about 2 to 9, and in the print, the step wedge range is about 5-17 (a little harder to tell). The staining is roughly the equivalent of cranking up the contrast in silver printing to get darker darks and brighter whites. If the negative were not pyro stained, it would cyanotype print much flatter, even though it's also ideal for silver printing.