Salted Paper Prints: their past, present and future

Lauren Ashley-Irvine

Conservator of Photographs and Paper

The Victoria and Albert Museum is the custodian of one of the world’s largest collections of photography. The recent addition of the Royal Photographic Society (RPS) collection of 270,000 photographs includes numerous salted paper prints (Figure 1). The salted print process was a revolutionary, direct, negative to positive photographic process invented by William Henry Fox Talbot in 1839, which allowed multiple prints to be created from a single negative. However, depending on the precise process used, it can result in extremely light-sensitive prints. This article discusses the knowledge gained by the author by attending a highly-specialised conservation symposium and workshop. Details of the talks, which covered chemistry and process, preservation issues, current display practices, the history of the salted paper print as well as its contemporary use, will also be discussed.

In September 2017 the author travelled to Cambridge, Massachusetts for five days to attend Salted Paper Prints: Purpose and Process. A Collaborative Workshop in Photographic Conservation in order to develop an understanding of the care, conservation and long term preservation needs of the RPS collection of salted print material at the V&A and get to know other professionals in the field. Organised by the American Institute of Conservation (AIC) in partnership with Harvard Library and Harvard Art Museums, the symposium looked at contemporary approaches and research studies undertaken by cultural institutions across the world. The talks focussed on the latest analytical techniques, preservation issues, ethical exhibition and display practices, and historical manufacturing techniques.

The presentation portion of the symposium, held at Harvard University at the Harvard Faculty Club, was attended by over one hundred professionals in the fields of photographic conservation, science, curation and photographic arts. On the first day of the symposium the Northeast Document Conservation Centre, which had partnered up with the host institution, held a practical hands-on workshop. Amanda Maloney, Associate Photographs Conservator at the Centre, gave a short but very illuminating presentation on the history, chemistry and technique of salted paper prints. Following this, attendees proceeded to the conservation studio on site to try making their own prints (Figure 2). Although there are dozens of historic recipes for creating salted prints, the workshop focussed on four of them: a Fixed Salt Print, a Gold Toned and Fixed Salt Print, a Potassium Iodide (KI) Stabilised Print and a Sodium Chloride/Salt (NaCl) Salt Print (Figure 3). These processes became standardised as salted printing became better-known and used in the mid-nineteenth century. Using four different negatives, one print from each process was created using pre-sensitised paper.

The most straightforward process was the stabilisation-only technique. With this, the contact-printed paper is placed in a bath of either sodium chloride (NaCl) solution or potassium iodide (KI) for two minutes and left to dry. Washing and fixing is not carried out. Early photogenic drawings, which are also salted paper prints, were often stabilised in this way, which inhibits the fading of the image. ¹ In the second process, the printed image was washed and fixed using sodium thiosulphate (a common fixative). Sodium thiosulphate creates a more stable image because it removes a significant amount of the excess light-sensitive silver halides from the paper. ² A gold toning technique was also carried out for one of the prints. Because gold is a very stable element, when the printed image goes through this bath, it coats the silver particles embedded in the emulsion in gold, which results in a crisp, long lasting, more stable image. Three coatings were also applied to the two fixed salted prints: beeswax, albumen (egg white) and gum arabic. These were brushed on in sections, side by side, to both prints so a visible comparison could be made between them. Coatings were often applied to salted prints, as they were to other photographic and art works, to act as a protective layer and increase image clarity and contrast. ³

After returning from the symposium, the four salted prints were placed in front of a desk window and exposed to daylight for several months, half covered, to observe the changes. While some clearly visible fading and darkening occurred in the unfixed and sensitised salted papers, the salted prints that were gold toned and fixed in sodium thiosulphate remained unchanged to the eye (Figure 4). Knowing which processes are vulnerable to rapid fading and why, such as photogenic drawings, will help to inform the care and use guidelines of the objects in the RPS collection for future exhibition, display, loan or public viewing request.

In addition to gaining a greater understanding of the chemistry of salted paper prints, another important insight gained from the talks in Cambridge was how to make use of facsimiles in exhibitions in an ethical and effective way. There is a significant amount of this highly light-sensitive photographic material in the RPS collection so the possible use of facsimiles in place of the originals is interesting, as is the potential involvement of contemporary artists in their production. The talk by Dan Leers, Curator of Photography at the Carnegie Museum of Art, focussed on the importance of using facsimiles of salted paper prints in exhibitions in place of originals and looked at how different museums and galleries across the world carried this out (Figure 5). As an example, he showed a photogenic drawing created by William Fox Talbot made in 1835, called Linen. This print had been on exhibition at the Getty in 1989 and had faded significantly after only five weeks on display. The British Library displayed facsimiles, created by curator John Falconer in their Beyond Photography exhibition, in place of sensitive originals. The National Library of Scotland’s Sun Pictures and Beyond exhibition in 2017 also made use of reproductions, as did the Carnegie Museum of Art in the recent exhibition William Henry Fox Talbot and the Promise of Photography where the highly light-sensitive photogenic drawings were replaced by facsimiles. Another alternative to displaying the originals with facsimiles was the use of virtual reality (VR) for Thresholds , organized by Somerset House and Photo London in 2017. An interactive VR experience was developed by the artist Mat Collishaw and VMI studios in London; it recreated the world’s first major photography exhibition and allowed visitors to interact with very early Fox Talbot prints.⁴

The topic of contemporary creation of salted paper prints was also discussed by a number of speakers at the symposium. Both artists and photographers presented talks on how to re-create this historic photographic method to create modern reproductions. Using the same historic materials such as salted papers and silver nitrate emulsions produces more convincing facsimiles than digital prints because they have the same tactile look and feel. The benefits of using this approach with salted prints is that modern, more realistic copies can be shown for the duration of an exhibition in place of the highly light sensitive photographic originals-thus prolonging their life.

Attending the symposium helped shed significant light on how salted paper print collections can be preserved and utilised. It was also a wonderful opportunity to gain knowledge of this remarkable photographic process, build international networks and share information. The special benefit of a workshop should not be underestimated; there is no substitute for the insight that comes from creating a replica. That the V&A’s new Photography Centre could engage artist/photographers in producing facsimiles and use those facsimiles to preserve unique objects would be a great outcome, both preserving skills and making more images available; education and access, two of the V&A’s core values.

Acknowledgements

Attendance at this symposium was made possible with a Jonathan Ruffer Curatorial Research Grant from Art Fund.

References

1. Maloney, Amanda. “History and Craft of Salt Prints.” Salted Paper Printing Workshop, 13 September 2017, Northeast Document Conservation Center, Andover, MA. Workshop Session.
2. Maloney, Amanda. ‘History and Craft of Salt Prints.’ Salted Paper Printing Workshop, 13 September 2017, Northeast Document Conservation Center, Andover, MA. Workshop Session.
3. ‘Characteristics of Salted Paper Prints.’ Salt Prints at Harvard, 2018. Accessed 7 February 2018. https://projects.iq.harvard.edu/saltprintsatharvard/characteristics-salted-paper-prints
4. Collishaw, Mat. Thresholds, 2017. Accessed 7 February 2018.  https://matcollishaw.com/