A thin pamphlet holding a couple of pages of printed text, a handwritten letter, and four somewhat hazy prints, held by the Rijksmuseum Research Library, caught the attention of the Rijksmuseum’s photograph conservator Martin Jürgens four years ago. What did the pamphlet’s German title, Phototyp nach der Erfindung des Prof. Berres in Wien, actually mean? What is a Phototyp, and who was Prof. Berres? As it turned out, this booklet holds a key position in the histories of both photography and printing; in addition, it is one of only three original copies known worldwide today.
To examine Berres’ procedure and the Phototyp, Martin started a collaboration with Ioannis Vasallos, currently at the National Library of Scotland, Edinburgh and Lénia Fernandes, now at the Nederlands Fotomuseum, Rotterdam. The story begins with the announcement of photography, in the form of the daguerreotype, at a joint meeting of the Académie des sciences and the Académie des beaux-arts in Paris on August 19, 1839. The daguerreotype was a fabulous thing: a polished, silver-plated sheet of copper holding an extremely sharp and detailed photographic image, which was made up of sub-microscopic particles of silver-mercury amalgam (and sometimes gold), that had fixed upon it a mirrored view of the world as seen through a camera lens.
Eight months later, in Vienna, a short note in the Wiener Zeitung of April 18, 1840 created a significant stir: ‘Prof. Dr Berres of Vienna has, by means of a series of experiments, […] made [daguerreotypes] suitable for duplication by means of a very simple method of printing. This new discovery is of incalculable use for the arts and sciences […].’ This was a tantalizing claim, since a daguerreotype was essentially a unique object that could only be duplicated by re-photographing it. Joseph Berres (1796-1844) himself described in detail his process of etching daguerreotypes in acid, inking up the plates, and pulling prints from them on paper. This sparked interest among academics worldwide, and the members of the Koninklijk-Nederlandsche Instituut van Wetenschappen, Letterkunde en schoone Kunsten in the Hague requested and received a copy of Berres’s booklet Phototyp, produced in August 1840. Designed as a sort of advertisement for his work, Phototyp consisted of a printed description of Berres’ process and its potential applications and a small number of intaglio prints pulled directly from etched daguerreotypes. Three of the prints in the Rijksmuseum booklet are photographic reproductions of engravings, and one is a view taken of the Saint Stephen’s Cathedral in Vienna.
The principle theory of etching daguerreotypes and printing from them is actually simple: the particles that form the highlights of the daguerreotype image act as an inhibitor to the nitric acid etchant, which reacts with the pure silver shadow areas first. The final etched daguerreotype becomes a positive intaglio plate, on which the shadows are etched deep enough to hold ink, and the highlights essentially remain un-etched and can therefore be wiped clean of ink.
The Rijksmuseum photograph conservators were curious about the overall low contrast of Berres’s prints and decided to re-create his technique. Following Berres’s instructions, and in collaboration with contemporary Dutch daguerreotypist Marinus Ortelee, ungilded daguerreotypes were created on pure silver plates as etching samples. Much research and experimentation was necessary to etch the plates successfully, and it became clear that the 19th century recipes needed to be adapted to match today’s materials and methods.
The contemporary recreation of Berres’s process demonstrated that his technique did actually work, but its weaknesses also became clearer: the fine image particles that form the daguerreotype image are simply not robust enough to resist the acid, which results in poorly etched plates and low-contrast prints.
SEM analysis of test plates before and after etching revealed that not just the shadows had been etched, but that the highlights had also been attacked by the nitric acid. As a result, the highlight areas on the plate could not be wiped completely clean of ink, and therefore printed with a light grey tone. At the same time, the shadows had not etched deep enough to hold sufficient amounts of ink to print dark enough to give the image adequate contrast.
Despite being able to reproduce with the ‘minutest exactness’, it didn’t take long for Berres’s process to be dismissed as a curiosity, and the general demise of the daguerreotype process in the eighteen-sixties finally rendered its use as a printing plate obsolete. Joseph Berres passed away at the age of forty-eight on Christmas Eve 1844. Of the hundreds of prints that he claimed to have made, a mere forty-eight have been found so far in an on-going survey. However, his legacy is great: in the era before photomechanical printing, Berres proved that photographs could actually be multiplied and used to illustrate publications. It is to be hoped that further research will expand our understanding of his pioneering role in printing photographs in ink.
With many thanks to Martin, Ioannis and Lénia.
Note: A detailed article entitled ‘Joseph Berres’s Phototyp: Printing Photography in the Service of Science’, is published in the Rijksmuseum Bulletin, 2018/2, pp. 144-69.
 ‘Wissenschaftliche Nachrichten’, in Wiener Zeitung, April 18 1840, p. 737. Translated by the authors.
 This is the copy now held by the Rijksmuseum.
‘Method of permanently fixing engraving and printing from Daguerréotype pictures’, The Mirror of Literature, Amusement, and Instruction 1007 (30 May 1840), p. 364.
‘… ils sont déjà très-curieux, et ils ont démontré que la gravure est possible’. Charles-Louis Barreswill and Alphonse Davanne, ‘Applications de la photographie’, in Chimie photographique, Paris 1864, p. 271.
 ‘Verstorbene zu Wien’, Wiener Zeitung, 31 December 1844, p. 2792.