A Visit With Mark Nelson

Today, I spent a couple of hours talking with Mark Nelson, an accomplished photographer, master printer, and the author of Precision Digital Negatives (aka the PDN system). Mark and I spoke a few weeks ago about his workshops and private tutoring in the PDN system, but it didn’t take me long to realize that his workshop is beyond my budget. Mark, however, was gracious enough to invite me into his home and workplace. He shared some of his personal thoughts about making photographs, digital negatives, platinum prints and photogravure prints.

Mark took a look at some of my recent silver gelatin and digital prints. His lack of comment was telling. He said, “Some photographers reach a point where they get it. It’s a kind of awakening and can be sudden in its realization.”

When Mark got it, he said, he tore up his entire portfolio—and started over.

Platinum vs Silver Gelatin

As I digested this idea, Mark opened his current portfolio and showed me some of his platinum and photopolymer gravure prints. I’ve never held a platinum print before. Words, at least my words, can’t describe the visual impact of such masterful prints.

Lady With Irises – Platinum Print by M. Nelson, photographer

From a distance, some of the platinum images seemed darker than what I’ve come to expect based on silver gelatin prints, but a closer look revealed a wealth of detail hidden in what I thought were featureless shadows. Likewise, reduced contrast images, like a misty morning scene captured near the confluence of the Illinois and Mississippi rivers, conveyed a spectrum of light in which each tone, although overall very light, was distinct from the others.

Mark explained that when creating a digital negative in Photoshop, the screen image may show a full range of tonality—from background white to full black—but that skilled use of chemistry or exposure can render a print with a narrow contrast space that conveys the artist’s perception of the original scene.

Some of Mark’s prints, I noticed, appeared to be overmatted—while others weren’t. When I asked about that, he pointed out that there were no mats—what I saw is the indentation of the paper made by the American French Tool etching press.

“What’s that?”, I asked.

Photopolymer Plate Printing

Photopolymer plate printing, as I understand it, uses an etching made from a positive transparency imposed on a steel-backed resin layer and developed simply by washing in water. After processing, the plate is inked, wiped, and then the remaining ink held in the etched layer is transferred to a sheet of fine art paper pressed under great pressure against the plate. In the hands of a master printer, the result can be as stunning as any printed image—completely even, without any hint of screen, and rivaling the finest wet process photographic prints I’ve seen, including Mark’s own platinum prints.

Successful Digital Negatives

Mark talked about the fact that successful digital negative prints are all about densitometry, the measurement of light transmitted through a semi-opaque material or reflected by a surface. He explained that measuring the density or light blocking ability of a negative is done a number of ways. A densitometer (or spectrometer) is an expensive instrument if purchased new, but you may find some for sale on eBay at low cost. For accuracy, a densitometer is the best solution.


Mark noted that density values in percent black, a similar measurement to one made with a densitometer, can be obtained through the info palette in Photoshop. I’ve used this method myself to make curves. Scan a negative as 16-bit grayscale into Photoshop, open the info palette in grayscale mode , and use the eyedropper tool to sample the image.

As well as densitometers, and scanners, Mark told me that even a digital camera can provide enough data for his system to produce a Precision Digital Negative.

I enjoyed this visit, and appreciate Mark’s hospitality. He lives in a small house on a tree lined street in Elgin, IL, not far from where Rosanne and Dan Conner, of the 1980s hit TV show, Rosanne, presumably lived. Much of the space in his home is occupied by photographs, printing equipment, books, and a few musical instruments. We sat and talked mostly about printing, some of the people he has worked with over the years, and the book he published in 2004, Precision Digital Negatives.

I happened to have a copy of Peter Mhrar’s book Easy Digital Negatives with me, and Mark asked if he could take a look. He found the method in Mhrar’s book to be much like his own and maybe coincidentally, chose that opportunity to tell me that he holds a patent on his process.

I realized today how little I know about photography and art, but that’s a good thing. I thought to myself on the drive down that I don’t even know enough to know what I don’t know, and today’s meeting set me straight on that. A wise person told me that the difference between an apprentice and a master is about 10,000 mistakes. For now I’ll keep shooting, making mistakes and learning to master exposure, frame and focus. Maybe soon, I’ll also be making better digital negatives as I explore the PDN system. Thanks, Mark!

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