Digital Negatives with PDN+Piezography K7

[sanking]

If you have thought about making digital negatives for contact printing with silver gelatin papers you might be interested in the following information from Jon Cone.

http://www.piezography.com/PiezoPres...ital-negative/

Although I don't plan to contact silver gelatin I am pretty excited by Jon's work with the K7selenium set for digital negatives as it also offers a lot of possibilities for alternative printing with an all gray ink set, which in theory should give better results than a color ink set.

Sandy King

[Kirk Gittings]

Yes, I have been following this. It looks like it has allot of potential.

[Nathan Potter]

Sandy, I've been watching this with interest but I don't know what the selenium designation means. Does the ink contain elemental selenium in some quantity or a selenium compound that metamorphoses into something else on contact with the paper? Why would the all gray selenium set be much different in aspect to an all carbon set; particle size, shape, spectral absorbance?

My concern would be the poison hazard from using elemental selenium in a powder form on print paper, especially if the selenium is of close to nanoparticle size.

Perhaps Jon will elucidate on this here.

Nate Potter, Austin TX.

[Tyler Boley]

there is no selenium in the ink, the inkset was named such because of the hue similarity to selenium toned silver prints, when used as initially intended for inkjet prints. Why Jon selected that over the other sets that would potentially take to the substrate, not sure.

[mdm]

I saw that too but I am wary of the marketing speak. He strikes me as an ink salesman first.

[David Karp]

Thanks Sandy.

[Nathan Potter]

OK Tyler; I had thought that might be the case. Thus one can presume that the pigment is principally carbon with a trivial amount of dopant to yield a selenium effect on paper.
For large digital negatives one can presume that the selenium hue will have negligible effect on a silver print.

That all leads me to be a bit unclear about the purported advantages of this inkset over a standard all carbon set, short of possible improvements in dithering and profiles that could also be implemented with all Jons standard carbon sets. It sounds as though Jon designed this set specifically for paper.

Nate Potter, Austin TX.

[Peter J. De Smidt]

The pure carbon pigment ink sets that I know of, namely MIS Eboni based ones and Cone's sepia set, don't stick well to glossy paper, and that includes Pictorico film.

[clay harmon]

This is interesting. Basically, he is offering some pre-configured digital negative Quadtone RIP profiles for his inksets. For workers who are not inclined to develop their own QTR profiles, there might be some clear advantages, as long as they are willing to change out their Epson-branded inks for the Cone inks. It makes sense that having a full complement of variable-dilution/same-tone inks to carefully fill up the dither patterns would result in smoother-toned silver negatives.

It seems that there is a tacit admission that using the old PDN approach with the Epson drivers is more limiting than using the QTR approach when it comes to controlling banding and so forth. The way I read the article, PDN is primarily used as a tweaking tool to fine tune the profiles.

Of course, many of us have been successfully using QTR and our own home-grown profiles for years. It offers a very high degree of control. Recently my four year old printer starting developing a banding issue on the magenta ink head that was a problem on my negatives. I just dropped that ink entirely from my profile and recalibrated my profile slightly and it fixed the problem. If I were depending on the some colorized negative approach using the Epson driver, I would be out shopping for a new printer. The control offered by QTR is allowing me to keep using this printer.

[joncone@cone-editions.com]

There is no selenium in the ink. The ink was originally designed as a tribute to Arnald Gassan - who was my teacher. Arnald was in the very late stages of his illness and I asked him to provide me with a silver print that I would replicate in tone (hue) and produce as an ink set. He sent me a fiber print that had been selenium toned. He had hoped to make an archive print of each of his negatives that he was hurrying to digitize as reference for his estate collection which was being organized.

This ink set was the original PiezoTone Selenium Tone released back in 2002. It is still in widespread use. But, later in 2005, when we learned how to encapsulate pigment particles we decided to replicate this ink set a second time in seven shades rather than the four shades of PiezoTone. We essentially encapsulated each pigment particle multiple times so that it would be compatible with glossy papers. Being compatible with glossy paper, it is also compatible with film. The ink when dried, does not rub off of these materials.

The other Piezography inks (with the exception of K7 Warm Neutral) are not glossy compatible except in their lightest dilutions. I do have customers making digital negatives with the Warm Neutral K7 inks. So it does not matter typically - whether the K7 Selenium or K7 Warm Neutral ink set is used for film. All of the QTR curve architecture I provide works with either.

I used the Selenium because that is the ink set I most use for my own work - that and Sepia which is a pure carbon ink. The Sepia ink is gorgeous on matte papers - but I have not done the multi-encapsulation to it because glossy very very warm prints is not something that has ever been common and I don't think that anyone would really want a glossy print warmer than what Warm Neutral produces.

None of the ink I produce is toxic chemically - you would not want to however, ingest pigment. For that matter, you would not want to drink ink - but if you did for whatever foolish reason...it is non-toxic.

Jon

Sandy, I've been watching this with interest but I don't know what the selenium designation means. Does the ink contain elemental selenium in some quantity or a selenium compound that metamorphoses into something else on contact with the paper? Why would the all gray selenium set be much different in aspect to an all carbon set; particle size, shape, spectral absorbance?

My concern would be the poison hazard from using elemental selenium in a powder form on print paper, especially if the selenium is of close to nanoparticle size.

Perhaps Jon will elucidate on this here.

Nate Potter, Austin TX.