Graham Cook has undertaken further experiments with platinum and palladium printing to refine print quality. Previous printing sessions using the ratio method resulted in a graining effect as a result of adding a higher amount to ferric oxalate 2# to the sensitizer to achieve the desired contrast. After additional reading and a discussion with established platinum printer Mark Voice Cook decided to use the dichromate method which mixes potassium oxalate developer with a small amount of potassium dichromate acting as contrast agent. Traditionally this makes it possible to establish graded developers for different types and densities of negative rather than mixing the contrast agent with the sensitizer for a standard outcome. However, the benefit of digital negative production is the ability to adjust and optimise contrast within individual transfer film negatives using Photoshop enabling much more quantifiable results. Cook also experimented with double coating paper which promotes a contrast boost creating richer blacks richer and more apparent depth of tone in the image, however the second coat is more difficult to apply accurately.
Cook explains his fascination with the process “What attracts me to platinum & palladium printing is the combination of digital technology and a 19th century photographic process. The craft of creating hand coated prints with the archival stability to last for many generations to come is very satisfying in an age of transient imagery. The subtle range and depth of print tone and temperature achieved through changing and fine tuning chemistry and materials in platinum & palladium printing deliver a unique print, this feels infinitely more precious than a silver gelatin print when held and viewed.“
Cook feels there is more to come “While the image content I am currently printing relate and are enhanced through platinum & palladium printing, as with any combination of photographic process and subject matter there could be other subjects that would respond equality well, so the next phase will be to experiment with genres other than landscape. The two images are pure palladium prints and where originally shot on a Mamiya 7II medium format camera in Ihlara Valley, Turkey.”