The series consists of two glass negatives taken of aerial photographic survey print mosaics at a scale of approximately 850 feet to one inch. The recording agency was responsible for geodesy; and, the medium and small scale topographical mapping of Australia for Commonwealth purposes. Geodesy is the branch of applied mathematics that determines the shape and area of large tracts of country, the exact position of geographical points, and the curvature, shape, and dimensions of the earth. Negatives of photographic print mosaics provided an additional check for the accuracy of aerial photographic surveys. After the aerial photographic survey film was developed the negatives were annotated with control information (e.g. individual photograph numbers, control points, flight information, etc) and given an initial check for accuracy (e.g. possible gaps in photography caused by camera failure, etc). The annotated negatives were printed and the prints laid out forming a mosaic. The mosaic (also known as a lay down) was checked to see whether any lateral gaps existed in the photography due to navigation failures during survey flights. The mosaic was then photographed, producing (in the instance of this series) glass negatives. If gaps were found the negatives of the print mosaics would be printed. Prints of the lay down would be sent to the operators who produced the aerial survey and used as reference guide to do a re-fly of the gaps. This system allowed for more accurate identification of gaps in the photography and minimised the amount of flights required to obtain complete coverage. The series entered Archives custody without a registered system of arrangement and control. Due to a lack of control information on the items the series has been controlled by a single number system for the negatives. Sources Series documentation Geoscience Australia, ‘Our History’, downloaded 5 May 2009 from http://www.ga.gov.au/about-us/history.jsp Geoscience Australia, ‘Aerial Photography’, downloaded 5 May 2009 from http://www.ga.gov.au/remote-sensing/aerial-photography/ Arctic Institute of North America's publications server, ‘Photographic Operations of the Royal Canadian Air force’, downloaded 29 June 2009 from http://pubs.aina.ucalgary.ca/arctic/Arctic3-3-150.pdf Arctic Institute of North America's publications server, ‘Photographic Operations of the Royal Canadian Air force’, downloaded 29 June 2009 U. S. Army Corps of Engineers Staff, American Society of Civil Engineers, ‘Photogrammetric mapping’, downloaded 25 June 2009 from http://books.google.com.au/books

Related series unregistered

International Index of Australia (Grid Map) Grid Index Cards to International Index of Australia.