Digital Prints

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Mastering Digital Printing
Digital Negatives for Photography
There is a mini-renaissance of antique printing methods going on in the photographic
world. Cyanotypes, kallitypes, gum bichromates, bromoils, and platinum and palladium
prints are popular examples. While many of these traditional photo techniques can now
be emulated or recreated digitally with image-editing software like Photoshop, purists stick
to the old-fashioned methods, which many times require contact printing with full-size
negatives. The modern-day twist on all this is that many of these photographer-artists are
now turning to digital printing to make the digital negatives.
Fine-art photographer Dan Burkholder pioneered the use of digital negatives in 1992, and
he helped popularize the process with the release of his groundbreaking book Making
Digital Negatives for Contact Printing in 1995, now in its second edition. Burkholder, who
states that “over a decade has passed since I made my last traditionally enlarged negative
via wet processing,” also maintains an active website (www.danburkholder.com) with
updates to his custom Photoshop Curves that are crucial to the process.
There are two basic ways to print full-size digital negatives: sending a file to an imagesetter
or digital photo print device, and printing on an inkjet.
For the highest quality—for example, in printing to silver gelatin black-and-white paper—
you can’t beat a service bureau imagesetter, especially one running at 3600 dpi or even
4800 dpi resolution. Grayscale images are used to create either a diffusion dither bitmap in
Photoshop or a traditional but high LPI output to a full-size film negative that is then contact-printed
to the final paper. Finding a service bureau that understands this process is
not easy, and the negatives are not inexpensive to produce, especially at large sizes, but the
quality is excellent and the result can rival the best optically made prints.
For the inkjet version, here are two basic methods: (1) For silver-gelatin printmakers,
images are converted to grayscale, adjusted with Curves, inverted to negative (in
Photoshop: Image > Adjust > Invert), and printed on Epson’s Glossy Film or Pictorico Hi-
Gloss White Film with all four or six printer colors; or (2) for an alternative process where
white films would block the UV light, images are adjusted with Curves, inverted, and then
colorized using 0/55/55/0 CMYK values to produce an orange negative (Burkholder calls
them “orange, spectral-density negatives”) that holds back some of the UV light used in
platinum/palladium, cyanotype, etc. photo printing. This orange mask effect is needed
for the heavier ink loads of printers like the Epson 1280 when printing on Pictorico OHP
film, although Burkholder admits that the Epson 2200 “is making terrific negs for both
silver and platinum prints with no colorization of the neg needed.”
Burkholder has a supplement to his book (Inkjet Negative Companion) that describes a
semi-automatic way to do the required steps in making digital negatives.
While the quality of a typical inkjet negative is not as good as one made with an imagesetter
(some users report a certain graininess with inkjet negatives), this method is very
adequate for alternative-process printing. Burkholder also suggests improving the tonal
range by making two negatives that are pin-registered when exposing the final prints—
one negative just for shadow detail and one for the highlights.