Map Compilation in the Canberra Office
Introduction
While map compilation was one of the main roles of the National Mapping Melbourne office almost all of the 1: 100,000 scale map components of a 1: 250,000 sale map sheet were compiled by the Canberra office.
Map Compilation in Canberra
Map compilation required access to large and heavy photogrammetric plotters. These plotters allowed the operator to view the terrain captured on overlapping aerial photographs in three dimensional space. From this view the operator could plot the required map features at map scale. Initially, Natmap Melbourne had Wild A6 stereoplotters and later moved to Wild B8 stereoplotters. The Wild B8 stereoplotter had been specifically developed to be used in conjunction with aerial photography acquired with the Wild RC9 superwide angle aerial camera. Aerial photography from the Wild RC9 aerial camera was selected to be the primary data source for Natmap’s 1: 100,000 scale mapping program. Over time as the State mapping agencies and private contractors acquired suitable stereoplotting equipment to handle the RC9 aerial photography they were used to contribute to the map compilation program.
In about mid 1971, Natmap’s Director Bruce Lambert decided to cancel the high precision traverse program. This estimated 8 year program was aimed at interconnecting the capital cities and so improve the existing Tellurometer traverse and triangulation. As part of this program the remeasurement of existing triangulation baselines was to be undertaken. Nevertheless, before the program’s cancellation, remeasurement of the traverses connecting the Johnston Origin to the capital cities of Perth, Adelaide, Melbourne, Sydney and Brisbane as well as the PAGEOS baselines, was achieved.
The Director’s decision saw the now spare resources in Geodetic Survey, Geodetic Branch Canberra utilised on map inspection/revision. The immediate result of the Director’s decision was that in January 1972 Peter O’Donnell and Brian Murphy were sent to the University of Melbourne’s Summer School of Photogrammetry. This 6 week course was conducted by Sjef Bervoets, Leo Rivett and Martin Spitzer and attended by some 15 to 20 international and national students. Ex-Natmapper Frank Leahy was then a tutor on the course.
Brian Murphy recalled that after completing Sjef Bervoets Summer School of Photogrammetry, I returned to Canberra and straight away set about familiarising myself with large stereoplotters, which had not been available at the University of Melbourne. Through Wally Wasserman at the Canberra College of Advanced Education, who was then setting up the surveying degree course at that institution, I was able to gain access to an ex-Natmap Wild A6 where I taught myself the relative and absolute orientation techniques on large machines. This stereoplotter however, was not designed to handle the RC9 superwide angle photography. Subsequently, I managed to gain access to an Australian Survey Office (ASO) Wild B8 stereoplotter in their London Circuit office, where I again taught myself how to drive it, armed with the valuable knowledge I gained on the photogrammetry course. The use of the unused ASO Wild B8 stereoplotter was organised through Dave Cook having a close connection with that organisation.
Circa 1970s photograph of Wild B8 stereoplotter at the Australian Survey Office’s London Circuit office, Canberra (XNATMAP photograph).
Brian Murphy subsequently taught John Woodger how to operate the Wild B8 stereoplotter and jointly they completed the photogrammetric compilation of a handful of 1: 100,000 scale map sheets in the region north of Albany, Western Australia, in Natmap’s area of responsibility. The completed compilations were sent to the Melbourne office for checking and were accepted, although in one sheet one or two higher value contours were found to have been omitted.
Paul Wise and Brian Murphy, 2018