Dr Ferdinand Hurter and Vero Charles Driffield discuss how a measure of daylight using an exposure calculator would help determine photographic exposures
The Hurter and Driffield Memorial Lecture 2022 is to explore how photography first played a crucial role in gathering legal evidence.
In her talk Moving Beyond the ‘Mug Shot’, Dr Jennifer Tucker will discuss how forensic photography was first used to prepare courtroom cases in the 1860s and 1870s. During a period of great change, colonial and metropolitan courts were redefining legal rights and practices – and photography was expanding rapidly on a global scale.
Associate professor of history at Wesleyan University, Connecticut, Dr Tucker has an interest in the connections between art and science, photography and mass visual culture.
‘Tichborne blended photograph’, reproduced in 'Admeasurement of Photographs, as Applied to the Case of Sir Roger Tichborne' (London 1873) by William S Mathews, private collection
The Hunter and Driffield Memorial Lecture, inaugurated in 1918, is organised by the RPS Historical Society. This year’s lecture will be at The Birmingham and Midland Institute on 25 October – two years after the event was last staged due to the Covid-19 pandemic.
Dr Ronald M Callender FRPS, who helped to forge the links between the RPS and Dr Tucker, explains: “Dr Tucker will demonstrate how the early use of photography to record the faces of criminals was extended to other applications – such as identity impersonation and pollution offences.
“Believing aspects of scientific and technical photography were marginalised in the histories of 19th- and 20th-century photography, Dr Tucker questions how photography was used, interpreted and, later, reinterpreted by others so as to argue for a renewed history of the role of photography in scientific investigation.”
Dr Callender has himself researched and written about photographic pioneers Dr Ferdinand Hurter and Vero Charles Driffield. Working together at Gaskell Deacon of Widnes, later the United Alkali Company, Hurter and Driffield collaborated on experiments which would revolutionise photography.
A commemorative medallion is given to the speaker at the Hurter and Driffield Memorial Lecture
“The two men measured daylight for every hour of every day for a year,” says Dr Callender, “using the data to design an exposure calculator that determined the ‘actinograph speed’ and thus provided the correct exposure for the photographic plate.
“Unwittingly, they had created a valuable tool – known today as sensitometry. The so-called H&D System survived until the outbreak of World War Two when it was replaced by a British Standard.”
The speaker at a Hurter and Driffield Memorial Lecture receives a medallion featuring the H&D characteristic curve, the exposing device, a light source and a density measuring device.
Hurter’s prototype actinograph that shows a modification for adjusting the exposure due to weather changes
The Hurter and Driffield Memorial Lecture 2022 will be delivered by Dr Jennifer Tucker at The Birmingham and Midland Institute at 6:30 PM BST on 25 October 2022