On new papers and coating observations
23 mars, 2010 par
On new papers and coating observations
Jon Cone

A recent comment on the popular Digital BW, The Print discussion list left me scratching my head yesterday…a little in disbelief at the responses to what seemed like a very benign observation by a monochromatic ink user. I suppose too, that I was confused how some black & white printmakers had missed the obviousness of the topic. Instead, they were conjecturing the most unusual of hypothesis to explain something that Piezography users have taken advantage of since the inception of PiezographyBW ICC in 2003.

For background to this, a long time Piezography printmaker whom I believe to be one of its absolute best practitioners, Tyler Boley, had been measuring the paper white point and the dMax and 50% gray of PiezoTone ink patches when printed on a variety of new papers.  He posted his measurements and observations on the Digital BW, The Print users list. I believe his observations concerning the papers were revealing of the source of some of these new sheets, because Piezography ink leaves a sort of investigative fingerprint in how uniquely it reacts to a particular coating on paper (coating/paper). Specifically, Piezography ink prints with a different color tone when a particular paper is used.

The long time Piezographer had sleuthed that Epson had obviously re-badged some new grades of papers! The discussion however, dissolved into a befuddled mystery of why a monochromatic ink system would change color from substrate to substrate. It was for me a duh! moment, and I wanted to reply that it was not a mystery at all and the answer had to do with light (the very substance of photography). But, clearly this users list was not a monochromatic ink crowd any longer. They were not going to get “it”, because they are not using monochromatic ink systems that interact with papers in the same way that Piezography inks do.

The Digital BW, The Print is now mostly comprised of users of color ink sets that have two or three shades of black. These ink sets are either in the form of a warm/cool color scheme (like the system illustrated below made by MIS) or have cyan, magenta, yellow inks (made by Epson, HP, Canon). These users actually produce black & white prints that are comprised of colorizing agents. In other words, they can make one ink set appear warmer or cooler by adjusting the color component inks when they are printed through software. While the printer may contain an ink set of up to seven and eight ink positions, they are using only two black shades (usually) or three (occasionally) for actual grayscale tonal division, while the other inks are color and employed to create the final tone (color) of the print.

MIS UltraTone color inks for black & white printing.

Piezography K7 was purposely designed to act in the opposite way. It derives its color from the paper rather than color ink. When Epson developed a printer with more than six inkjet heads (2200, 4000, 7600, 9600) the suppliers of monochromatic ink systems that had four gradations of black ink, split in two opposite directions. The only company that took advantage of dividing a grayscale into more shades of ink was Piezography – namely because Piezography always strives for the highest possible image fidelity. The other ink companies at the time, and there were many (Lyson, MediaStreet, MIS, Sundance), developed ink sets that were similar to Epson’s multi-toning ABW inks. They reduced the amount of black shades of ink and added color positions. Epson initially offered two black shades, but eventually offered three black shades in combination with two cyans, two magentas, and a yellow ink.

The new 3rd party multi-toning inks (just like Epson ABW) gave the convenience or flexibility of making any color of gray, but did so (and still do so) at the expense of image fidelity in comparison to four or more shades of black ink. Where it might be argued that the new fine droplet print heads permit a quality from three shades of black that is as good as the old four shades of black, seven shades is substantially better today than three. Five shades is better. Six becomes sublime. Seven is perfection!

In effect, all of these new systems that use two or three shades of black ink are sophisticated color printing systems used to make black & white prints, rather than true monochromatic ink systems. And, these systems are only able to divide a grayscale image into two or three partitions rather than seven like Piezography. While they are easy to profile, they lack the ability to render high resolution, smoothness of tone, and highlight and shadow detail in the way that the Piezography ink set can. It only takes a simple math equation to match the ability of a dot matrix dither to 256 gray levels. Three shades of black is not enough, and the color inks only give the illusion of smoothness by filling in the space between dots.

However, I’m not making judgement on the use of color toners to produce black & white prints. I actually developed a complex 11 ink system that comprised several color inks in order to produce the Ashes and Snow prints for photographer Gregory Colbert. I consider these prints to be some of the best work that I have ever produced. There were three color agents and eight shades of black in the final ink set which I named “tokyo”. There was actually a 12th ink that was a duplicate black used in conjunction with the first, by heating the paper to 50c. The “tokyo” ink set combined an unprecedented tonal fidelity with the flexibility of controlling three split tones. The mathematics and software involved in designing the 12 ink curves was as mind-boggling as it was challenging. But, rather than use color inks to produce black & white prints, I believe I used black & white inks to produce color prints. Colbert had been making color transfer prints before I was contracted to produce his last three exhibitions. For my part, I actually started with drum scans of 35mm b&w negatives and ended up with richly colored “monochromatic” styled images.

I am mostly opining about the art of using paper to influence the monochromatic print. It is a dying darkroom art from yesteryear, that is still common to Piezographers, but lost now on those using color inks to make black & white prints. Perhaps, I should digress a little and quantify the difference between a seven ink multi-toning ink system like MIS UT7 (one of the most current) and the seven shaded Piezography K7 monochromatic ink system on an identical printer – the Epson 2200. It’s easy to understand by looking at the amount of inks used to divide a grayscale image. The same difference will occur on the ink sets when used in the latest generation of printers.

In the following illustration is the MIS UT7 curve for producing a sepia black & white image on Premier Fine Art paper using the MIS UT7 inks with the QuadTone RIP software. Notice that only the yellow and black ink positions are used. The black ink only must carry the entire range of grayscale while a warm colorant is used for color tone.

MIS UT-7 ink curve for Sepia on Premiere Rag.

In the following QuadTone RIP Piezography curve which is used with Piezography Sepia K7 inks for Hahnemuhle Photo Rag , seven separate shades of black ink are used in all of the printer’s ink positions to divide the grayscale image.

Piezography K7 curve for Sepia K7 inks on Hahnemuhle Photo Rag.

…too be continued, when I get to the point of what I was trying to explain about inks and paper observations in part two.

On new papers and coating observations
Jon Cone
23 mars, 2010
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