On the Piezography website, I documented several Piezography Digital Negative processes that are quite different from each other. While they are all getting to the same goal, they are doing it differently and bringing out different aspects of fine silver printing.
The last process I completed combines Piezography Selenium inks with Mark Nelson’s PDN Curve Calculator II. Selenium inks make the PDN process easier for those who don’t mind dedicating a printer to monochromatic inks. And it is a great remedy for those who experience dithering or striations with the normal PDN workflow that uses the Epson printer driver and Epson color inks.
With Piezography Digital Negatives, PDN is used only to generate contrast linearization curves for the final silver print – and so it is used only for the creative linearization possibilities it brings to Piezography digital negatives. Very little recalibration will be needed when using density based digital negs.
But prior to this is an earlier Piezography Digital Negative process that I designed to be pre-linearized at Gamma 2.2 for two silver papers: Ilford Multigrade IV RC and Fiber Base papers when used with Sprint chemistry. These Piezography QTR curves actually print what looks like a real negative from a positive image. It even prints that part of the film that is not filled with the image as a fully exposed film leader to act as a white border when contact printed. It also prints film base+ fog for the clear portions of the film. The QTR curve is also designed so that the widest possible range of Epson printers can produce a linearization between the film base+ fog and fully exposed film leader.
This produces extremely long shadows and highlights as a result. You have to want really long, long tone to use this process. Because it is pre-linearized, it should not be used with PDN as that would defeat the process. Piezography linearization is unique and it is proprietary. Piezography linearization produces a Gamma 2.2 response in the final silver print and is available only in this particular process.
And finally, there is also a general purpose film system that produces up to 3.0 dMax for any type of alternative process as long as you give the system the correct dynamic range in the original negative. This one can work with PDN also. I made it as a continuous tone system for back lit in which a fully opaque black is desirable.
Probably, the latest system is the most desirable for use with PDN. The QTR curves I designed produce a specific maximum density on the Piezography digital negatives ranging from 1.50 to 1.80. The dMin of the film in each of these five systems remains constant at 0.15. This is a variable dynamic range system designed to offer suitability to the widest range of silver papers and development techniques. When paired with PDN – it produces a synergy that allows the photographer to achieve silver prints that can be inspected with a loupe and yet can be linearized to the wide variety of contrast effects that PDN produces.
Still, all of these processes are in use by photographers. And some photographers are using more than one of the processes.