matching those of human vision. After 1983 this work was carried out within the then newly established Sowerby Research Centre of British Aerospace PLC at Filton, Bristol, the new facilities significantly aiding progress of the research. Much of the research in
the mid 1980's was carried out as part of the British government / industry / university
collaborative projects set up to develop advanced computer techniques under the Alvey
Directorate. During this collaborative activity he was able to interact not only with researchers both in industry and universities in the UK, but also to a limited extent with visiting researchers from abroad, including David Marr of MIT fame and John Canny, the 'inventor' of the Canny Edge Detector which has since become effectively a ‘standard’ for such operations (but see ‘Canny & SHV comparison.pdf’)..
As a result of his research in the 1960's and early 1970's he has been an Associate
Member of the Royal Photographic Society (RPS), a member of the Institute of Physics
and an Member of the Institution of Electrical Engineers (IEE) (now part of IET) for many years. Also, late in 1979, he was invited to sit on two committees of the CIE (Commission Internationale de l’Eclairage), one of which (TC 1-17) he remained a member of until his retirement. Much of the conceptual background to his modelling of visual threshold performance and the related search modelling was incorporated in the Technical Report of the CIE Technical Committee TC 1-17 “Contrast and Visibility”.