2015: International Year of Light and Light-based Technologies


Peter Fischli, David Weiss, 1989. Colour photography. Collection of Prints and Drawings ETH Zurich

ETH-Bibliothek provides specialist information on all aspects of light and light-based technologies. To mark the International Year of Light 2015, the following gives an overview of important works and holdings. 

Light research in the seventeenth century

Development of the electrical telegraph in the nineteenth century

Development of perspective during the Renaissance

The Knowledge Portal serves as a search tool to help you find answers to specific questions

Moreover, extensive historical holdings document the importance of astronomy as a branch of research at ETH Zurich for one thing, and for another, they explain the key role that ETH Zurich played in the development of photography and the role that photography took on in academic life. 

Researching the sun at ETH Zurich

For over a century, solar research was the main focus in astronomy at ETH Zurich. It was conducted and shaped by three astronomers:

  • Rudolf Wolf (1816 to 1893)
  • Alfred Wolfer (1854 to 1931)
  • Max Waldmeier (1912 to 2000)

Even before his appointment as the first professor of astronomy at the Federal Polytechnic Institute, as ETH Zurich was known at the time, Wolf had already begun to collect and analyse observations on sunspots. In Zurich, as the director of the Federal Observatory, he transformed his institute into a renowned centre of solar research.

From the observatory constructed by Gottfried Semper to Wolf’s specifications, the astronomer initiated the systematic study of changing sunspots. Based on the data gathered, Wolf discovered the sunspot cycle of around 11.1 years. 

Sunspot drawings

5 April 1894
ETH-Bibliothek, University Archives, Hs 1304:1572

Wolf's successor, Alfred Wolfer, continued with the observation of sunspots. This time, a projection was used to sketch the spots on a standardised grid. William Brunner and Max Waldmeier carried on using this system of observing and counting sunspots until 1980. Today, ETH Zurich’s University Archives contain 28,000 sheets with sunspot drawings spanning a century (external link).

Max Waldmeier, whose personal papers (pdf, 3.63 MB) (external link) are kept at ETH-Bibliothek, also focused on researching the solar corona, which can be observed perfectly in a total solar eclipse. This prompted Waldmeier to embark on several solar eclipse expeditions to Africa, Asia and South America in the 1950s and 1960s. Waldmeier's shot of a solar corona was taken during the period 1961 to 1963.

Photography as a research field and medium for scientific communication

After their discovery, intensive research was conducted into the optical and photochemical processes involved in photography. The techniques used to record images were analysed, improved and constantly refined. By the same token, photographs were used to document and illustrate scientific observations and research results. Moreover, photography proved to be an effective publicity tool to present academic life.  

Consequently, the Photographic Institute founded at ETH Zurich in 1886 fulfilled a dual purpose: it produced photographs on behalf of researchers and the university and conducted its own research in the field of photography. Today, the Photographic Institute’s image holdings are kept in ETH-Bibliothek’s Image Archive. Examples reveal how the institute not only recorded its own work in pictures, but also its results.   

For a long time, spectacular magnesium flashes were part of the repertoire of artificial light sources. This shot was taken in 1928.

Under the direction of Professor Ernst Rüst (1878 to 1956), the Photographic Institute conducted numerous problem-based studies on photography. These included exposure measurements outdoors, which were conducted on the Jungfraujoch in 1936 within the scope of UV research.

Microphotography provided images of structures that were invisible to the naked eye. The Photographic Institute specialised in this technically demanding branch of photography. The micro-image of cells was taken in 1929, the view into the microphotography room in 1955.

Numerous images from the Photographic Institute's holdings can be viewed on the platform Image Archive Online (external link). A search tool for the complete holdings (pdf, 1.02 MB) (external link) is also available online.

Monika Burri's publication Science in Sight – Scientific Photographs from the Image Archive, ETH-Bibliothek (external link) focuses on the institute and image holdings.