In 1870 H. C. Russell was appointed Government Astronomer at Sydney Observatory. He quickly grasped the significant role photography was beginning to play in astronomy and by the end of the nineteenth century Sydney Observatory had embarked on several photographic projects of international significance.
The first of these was organising the New South Wales contingent of observers for the 1874 transit of Venus. The second was the mapping of the stars in the southern section of the heavens using photography. Often referred to as the 'Carte du Ciel' or ''Mapping the Stars'' project, Sydney and Melbourne observatories, were responsible for the belts of the sky covering -52° to -64° and -65° to -90° respectively.
The planning for this began in 1887 and in July 1890 James Short was appointed to the observatory staff to operate the 'Star Camera'. Between 1890 and his retirement in 1930 Short produced almost all of the photographs taken with the Sydney 'Star Camera'. By 1891 H. C. Russell and James Short had gathered enough equipment to start a series of photographic experiments for the 'Mapping the Stars' project. The telescope they used was officially known as an 'astrograph' but Russell often referred to it as the 'Star Camera'. Its casing and mounts were made in New South Wales and the lens, ordered in 1887, was made by Sir Howard Grubb.
While Short and Russell had experimented with the camera in 1890 using a 6 inch Dallmeyer portrait lens none of these results were taken to the standards set by the 1887 convention. By June 1891 the Grubb lens and an extra enlarging lens arrived at the observatory and it was these that Russell and Short experimented with.
These photographs although taken using the correct lens and the astrographic camera were not accepted for the ''Mapping the Stars'' project. The reason for this was that the reseaux for this project were all to be made in France, to a standard size and precisely graduated scale. These then needed to be thoroughly tested before being sent out to each participating observatory. Unfortunately the reseau Russell was experimented with was an untested one sent to him by Admiral Mouchez, the Director of the Paris Observatory, making them inadmissible for the 'Carte du Ciel' project.
Russell and Short conducted their experiments with both the Grubb and Dallmeyer lenses while waiting for the reseau to be completed by Gautier in Paris. It seems that two star groups, Kappa Crucis and Eta Argus (now known as Eta Carinae), occupied their attention throughout 1891 and the museum holds a number of these early experimental plates taken using the astrograph.
Russell described some of the experiments to the New South Wales Royal Society in July 1891 … I am able to shew [sic] you three plates, one exposed thirty seconds, another two minutes, and a third thirty minutes, on the well known star Kappa Crucis. You will see thirty seconds is enough to get images of stars to the 9th magnitude, and that two minutes gives images of stars to the 11th magnitude, and takes in also some of the 12th and one of 13th magnitudes.
The plates were exposed one after another, on a night that seemed uniform, and when the two minutes plate was a success the thirty minutes one ought also to have been.
These photographic plates are of scientific significance both for their international role in the ''Mapping the Stars'' project as examples of the experimentation phase in the first years of using the star camera. They are also of immense significance due to their relationship to Australia's early scientific history, its scientists and the instruments used to create the photographs.
Geoff Barker, September 2008
The first of these was organising the New South Wales contingent of observers for the 1874 transit of Venus. The second was the mapping of the stars in the southern section of the heavens using photography. Often referred to as the 'Carte du Ciel' or ''Mapping the Stars'' project, Sydney and Melbourne observatories, were responsible for the belts of the sky covering -52° to -64° and -65° to -90° respectively.
The planning for this began in 1887 and in July 1890 James Short was appointed to the observatory staff to operate the 'Star Camera'. Between 1890 and his retirement in 1930 Short produced almost all of the photographs taken with the Sydney 'Star Camera'. By 1891 H. C. Russell and James Short had gathered enough equipment to start a series of photographic experiments for the 'Mapping the Stars' project. The telescope they used was officially known as an 'astrograph' but Russell often referred to it as the 'Star Camera'. Its casing and mounts were made in New South Wales and the lens, ordered in 1887, was made by Sir Howard Grubb.
While Short and Russell had experimented with the camera in 1890 using a 6 inch Dallmeyer portrait lens none of these results were taken to the standards set by the 1887 convention. By June 1891 the Grubb lens and an extra enlarging lens arrived at the observatory and it was these that Russell and Short experimented with.
These photographs although taken using the correct lens and the astrographic camera were not accepted for the ''Mapping the Stars'' project. The reason for this was that the reseaux for this project were all to be made in France, to a standard size and precisely graduated scale. These then needed to be thoroughly tested before being sent out to each participating observatory. Unfortunately the reseau Russell was experimented with was an untested one sent to him by Admiral Mouchez, the Director of the Paris Observatory, making them inadmissible for the 'Carte du Ciel' project.
Russell and Short conducted their experiments with both the Grubb and Dallmeyer lenses while waiting for the reseau to be completed by Gautier in Paris. It seems that two star groups, Kappa Crucis and Eta Argus (now known as Eta Carinae), occupied their attention throughout 1891 and the museum holds a number of these early experimental plates taken using the astrograph.
Russell described some of the experiments to the New South Wales Royal Society in July 1891 … I am able to shew [sic] you three plates, one exposed thirty seconds, another two minutes, and a third thirty minutes, on the well known star Kappa Crucis. You will see thirty seconds is enough to get images of stars to the 9th magnitude, and that two minutes gives images of stars to the 11th magnitude, and takes in also some of the 12th and one of 13th magnitudes.
The plates were exposed one after another, on a night that seemed uniform, and when the two minutes plate was a success the thirty minutes one ought also to have been.
These photographic plates are of scientific significance both for their international role in the ''Mapping the Stars'' project as examples of the experimentation phase in the first years of using the star camera. They are also of immense significance due to their relationship to Australia's early scientific history, its scientists and the instruments used to create the photographs.
Geoff Barker, September 2008
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