Time to take my proof of concept for analog trichromes to the next level.
I shot these photos on an expired roll of Ilford Delta 400. It was about 20 years expired, and I metered at 200ASA. I didn't change the development time at all, under the assumption that overexposure alone would be sufficient to get good negatives.
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| The initial digitally-made trichrome, for reference. |
This process is simple enough to create on a computer, but I wanted the challenge of creating a fully-analog color photograph. This particular roll of film gave me trouble printing because it still had a tendency to curl even after drying. But the result was good enough as a proof of concept.
For printing with cyanotypes, the RED filter is used for the CYAN layer, the GREEN filter is used for the MAGENTA layer, and the BLUE filter is used for the YELLOW layer.
The yellow layer came first, and the exposure seemed good. All details were clear. This layer was exposed for 120 minutes.
The magenta layer, in this case using cuprotype instead of cyanotype, developed a little stronger than I wanted, overpowering the yellow quite a bit. The exposure time for cuprotype is much longer than for cyanotype, so I think I can reduce the exposure time by a fair amount, hopefully at the same time increasing contrast. I did mess up the alignment here though, my bad... This layer was exposed for 60 minutes.
The final cyan layer was the trickiest to balance. Too much exposure and the cyan is way overpowering. I think I got pretty close here but the magenta/red is still very strong. This layer was exposed for 40 minutes.
Overall it's pretty obvious that the magenta/red layer completely overpowers the print. The pure white (or light grey) on the front of the cap is far too red. But aside from alignment issues, I'm pretty happy with how this turned out. At least it proves the concept, and leaves room to make adjustments for the next attempts.
