Daniel Walding is Senior Photographic Technician for Australian Institute of Aboriginal and Torres Strait Islander Studies
Lantern slides are a unique format that were in wide use from the 18th to mid-20th century and allowed glass photographic transparencies to be displayed using a magic lantern projector. They were often shown to large groups of people as a form of entertainment, and are referred to as a precursor to cinema. Content was often enhanced with hand colouring and oration to provide a narrative.
AIATSIS has around 850 lantern slides across 18 sub-collections in its Pictorial Collection. The majority of these slides were collected and used by missionaries including Ernest Brainwood, Herbert Read and Arthur Mathews from the early 1900s to the mid-1940s. These document the people and activities undertaken at UAM (United Aborigines Mission) and other missions across Australia.
The photographic digitisation team at AIATSIS recently re-visited the lantern slide digitisation process subsequent to the purchase of a high resolution 200 megapixel Hasselblad H5D multi-shot camera and the establishment of a dedicated photographic studio suitable for these types of work.
Lantern slides often have printed or handwritten detail on the external paper wrapping and when scanned on flatbed scanners, these external details are cannot be made visible at the same time as the image detail. This meant we weren’t fully preserving the entirety of the format.
AIATSIS staff developed an innovative solution that enabled us to capture both the transparent and reflective elements of the format in a single capture that didn’t require any complex compositing or post-production work.
We used a light table to provide the transparent window of the slide with bright and colour neutral illumination. The light table had been retrofitted with high quality LED lighting strips that had a CRI (colour rendering index) of 98 out of 100. Resulting in very good reproduction of the entire colour spectrum.
We positioned the lantern slides some distance above the light source to ensure there was satisfactory diffusion and to prevent any variations in light intensity across the image area. The light table and copy area was fully masked and covered with thick black fabric to ensure no light escaped and caused any flaring in the camera lens or from other reflective surfaces.
We then used a strobe flash light directly aimed at the top surface of the lantern slide and bounced that light using a small white reflector card to ensure even illumination across the top surface.
Polarising filtration was used in front of the light source and on the camera lens to ensure any specular highlights or flaring from the flash was minimised to ensure the best possible digitisation outcome.
This approach gave us a robust solution for quickly and efficiently capturing all lantern slides held in the AIATSIS collection in a sympathetic way that showcases this special and unique format. By capturing the entirety of these objects we have provided a better rendition of the entirety of the collection item and better contextualises the image content and provides further valuable information to better interpret the collection.
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