This photograph was taken in 1907, when Alfred Lenehan, the Government Astronomer at Sydney Observatory was looking for a new site for Sydney Observatory. This photograph of the Observatory Advisory Board was taken at Mount Wilson in New South Wales. In it we can see from left to right; W. E. Raymond from the observatory staff, W. I. Macdonnell, C. J. Merfield, J. Brooks, H. A. Lenehan and E. Du Faur.

After looking at sites at Mount Wilson and Mount Canobolas in New South Wales the project was put on hold. For more information see associated Powerhouse Museum theme 'A new site for Sydney Observatory 1907'.

Geoff Barker, Curatorial, October 2008

References
Haynes, Raymond, Haynes, Roslynn, Malin, David, McGee, Richard, Explorers of the Southern Sky, Cambridge University Press, Cambridge, 1996

A stereo photograph is comprised of two photographs, one taken as the left eye sees the view and another slightly offset as the right eye would see a view. These photographs are mounted on a card which is then fitted into a viewer. The viewer allows the brain to superimpose the two images, imitating the three dimensional stereovision of the human eye.

Stereo photographs are essentially the combination of two inventions of the 1830s. Sir Charles Wheatstone announced the first of these in 1838; it was an optical viewer that could combine two specially developed three-dimensional drawings that took into account the slight variation between the right and the left eye. The second occurred in 1839 when two different photographic processes, the 'daguerreotype' by Louis Daguerre and the 'Talbotype' or 'Calotype' by Henry Fox Talbot, were announced to the world.

In the 1840s Sir Charles Wheatstone began experimenting with Talbot's process which enabled him to place two slightly offset photographic images in his viewer. The success of these experiments inspired a Scotsman, Sir David Brewster, to announce in 1849 his modification of the stereo format, a portable viewing device called a lenticular stereoscope. It was Brewster's stereoscope which defined the standard for the new format and which was popularised from the early 1850s.

Geoff Barker, August 2009.

References
William Darrah, 'The World of Stereographs', W. Darrah, 1997
Helmut and Alison Gernsheim, 'The History of Photography', Thames and Hudson, 1955, 253

Photographic print, stereoscopic, the Observatory Advisory Board at Mt Wilson, silver gelatin emulsion / cardboard, used by Sydney Observatory, Mount Wilson, New South Wales, Australia, 18 May 1907

Two black and white photographs (stereoscopic photo format) mounted on a black cardboard backing board. Both of the photographs show the Observatory Advisory Board: E Du Faur, H A Lenehan, J Brooks, C J Merfield, W I Macdonnell and W E Raymond, standing around a picnic basket and blanket during an expedition to Mt Wilson in NSW to assess possible new sites for the Observatory. There is a typed explanation of the photo glued to the back of the mount.

Photographed: Mount Wilson, New South Wales; 18/05/1907

In purple typed text on back of image 'No 1 May 18th 1907 / Advisory Board at Mt Wilson / re new site for Observatory. / Right to left E Du Faur / H A Lenehan / J Brooks / C J Merfield / W I Macdonnell / W E Raymond'.
In pencil on the back of the mount '1/34/a'.

P3549-89

18/05/1907

108 mm

177 mm