Pyro, digital negatives and alternative processes

Alex Tymków outlines a method of combining pyro, digital negs and alternative photographic processes in photographs.

Writer and Photography / Alex Tymków


This project began with my wanting to make a piece of work with some Comedia dell’arte masks I have, photographing them as still life and in performance. They are both beautiful objects and playful, but like most masks they also have a lightly sinister aura. It was these aspects I wanted to explore. As part of this exploration I decided to make the prints using two alternative photographic processes: new cyanotype, for blue prints, and Argyrotype, for brown. Both these formulations were devised by Dr. Mike Ware in bringing alternative processes up to date.

I began in the traditional way. Using a large format camera, in this case 5×4, I placed two of the masks on my windowsill and photographed them using available light. I followed the usual procedure for making the negatives: Ilford FP4 plus film, overexpose by one stop then overdevelop in Ilford ID11 by 80%. This gives a negative which will print well using many alt processes but is too dense for silver printing. fig 1. The disadvantage of working this way is that I was limited to a single size of print.

Developing large format film in PMK pyro

Another approach I had read about for making alternative photographic prints involved developing large format film in PMK pyro, without increasing exposure or processing time. Pyro produces a yellow stain in proportion to the developed silver and the filtration effect of this coloured stain equates to extra density when exposing by the ultraviolet light used for making alt prints. So, PMK Pyro developed negs could be printed both on silver gelatine paper and when using alternative processes. I exposed a sheet FP4 Plus at 125 ISO and developed it in PMK Pyro, then contact printed it using the new cyanotype process. The negative printed really well and very fast, but again, print size was restricted by the size of the camera negative.

Dan Burkholder, in his book Making Digital Negatives, outlines a method of producing enlarged negatives on an inkjet printer using acetate. Instead of printing onto the acetate using black ink he uses an orange colour, which absorbs the UV light and therefore equates to density. Burkholder gives some suggestions on increasing the contrast by using the Curves function in Photoshop and offers different Curve profiles for different processes. The advantages are clear: any format negative original can make any size print. The only limitations are the size of the digitised file and the maximum format of the printer making the acetate negatives.

pyro photographMy Fox Talbot Moment…

It then occurred to me that if I scanned a Pyro processed negative as a positive I could retain the colour of the stain. I should be able to print onto acetate without having to make any changes to the contrast. I exposed a roll of 35mm Delta 3200 and processed it in PMK pyro. Scanned and enlarged the image and printed it twice onto acetate.

Registered the two images on top of one another (to increase the density) and made a new cyanotype print. It worked!

My Fox Talbot Moment… I don’t know of anyone else using this technique. To make the body of work with the Comedia dell’arte masks shown here, I used 35mm Delta 3200 film processed in PMK Pyro. The prints were made using new cyanotype and argyrotype processes.

The procedure I used is as follows:

  • The negatives were scanned with a Nikon Coolscan IV negative scanner as a positive; this retains the characteristic yellow stain of the pyro development.
  • The scan is opened in Photoshop and the image inverted to a positive, it’s a dark blue colour. When working as a positive it is easier to crop, spot and resize.
  • The image is then flipped horizontally so that when printed out it will be the right way round when in contact with the coated paper (the same as with the emulsion of conventional film).
  • I resize the images to 15 cm along the long side at 300 ppi, choosing this size because I want to print each image twice onto the same piece of A4 acetate.
  • After resizing the image is inverted again to return it to a negative retaining the colour of the pyro stain.
  • Next the ‘canvas size’ in Photoshop is increased to 18 cm x 14 cm to create room for registration marks which have to be added to aid registration of the two identical images. It is easy enough to draw some.
  • The layers are then flattened to minimise the file size.
  • To complete the ‘artwork’ a new A4 document is opened and the negative (with the registration marks in position) is then copied twice onto it, with the copies positioned side by side.
  • The inkjet printer should be set to Photo Quality Inkjet Paper and 1440 dpi in the print dialog box and the image output onto acetate.
  • The acetate is then cut in two and the images held carefully in register using Selotape. It is not necessary to have a wooden split-back contact printing frame
  • The negative is taped to the coated paper with a masking tape hinge so the progress of the exposure can be checked. It is not necessary to have a wooden split-back contact printing frame, a Paterson plain glass frame is fine.
  • The print is exposed to ultraviolet light. The sun is the cheapest but not necessarily the most convenient – or reliable, especially here in England. I use a UV printing down unit equipped with a timer for easily repeatable results.

cyanotype print
I found using the combination of the high speed of 35mm Delta 3200 with the colour staining benefits of PMK Pyro development have given me an enormous amount of freedom. I didn’t need a studio – all the pictures were taken in my study at home. I used available light, or a combination of hand flash and available light. This project was successful on two counts. I produced a piece of work with which I’m very pleased; and I also made a technical discovery which I can now share with others. The whole series can be seen in my gallery on this site. I have had favourable reactions to the pictures, although some people have found plates 5, 6 and 7 disturbing – a middle aged man photographing himself in that manner and by so doing, taking alternative photographic processes beyond the pictorial.

Alex Tymków is a photographer and Senior Photography Technician in the School of Media & Photography, University of Plymouth, UK.

Book mentioned in the article:
Making Digital Negatives with an Ink-Jet printer

Making Digital Negatives with an Ink-Jet printer

by Mike Ware

8 of 10   Rated 8,5 – based on 2 votes

A 20-page downloadable workflow on how to make negatives.
Excellent value.


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