Gus Schaefer, the son of a Queensland sugar worker, was in his late-20s when he began work at the Munitions Supply Laboratories (MSL) in January 1941. Schaefer was a specialist in mathematics and analytical training and had been a teacher for some years. He rapidly learnt the fundamentals of optical design and ray tracing analysis. Schaefer's first task at the MSL was to analyse eight tons of optical glass from an American firm (reserve stock).
Schaefer used the book, The Manufacture of Optical Glass and Optical Instruments by F.E. Wright (1921) to learn how the USA had developed their optical munitions industry in the First World War. Interestingly enough, this book was also used as a reference resource by Australian Consolidated Industries and E.J. Hartung when they began to experiment with the production of optical glass.
When J.J. McNeill returned to the MSL in early 1942, Schaefer found a friend and workmate. The two shared a flat, worked late at the labs three nights a week, and played squash together. Their friendship was life long; they were even known as the 'Optical Twins' as their scientific skills complemented each other so well. McNeill had practical knowledge and formal training in technical optics and would intuitively solve problems as they arose; while Schaefer worked to understand the mathematical principles underlying the solution.
Schaefer's research for the Optical Munitions Panel included many years working on the one-metre infantry range-finder, an extremely complicated and difficult piece of optics which has various aberrations, including astigmatism. In a masterful piece of scientific detection work, the problem was eventually tracked down to the air gap between the two prisms.
Schaefer left the MSL in January 1951 to found the first Defence Operational Research Group, located in the Head Office of the Department of Supply in Melbourne.