On March 21, 2020, David Hearn, the former Managing Director of Stemmer Imaging UK, succumbed to his long and serious illness. Hearn had been at the helm of the UK subsidiary from the acquisition of Firstsight Vision in 2004 until his departure due to illness last year.

Hearn's first professional experience in the imaging industry was at Data Translation, where he was responsible for sales of PC-based data acquisition and imaging hardware and software. He then took over the management of Optimas and founded Vortex Vision in 1997. Wilhelm Stemmer, who sold very similar products in the German machine vision market, took a stake in this company at the time.

In 2001, Hearn and Williamson merged their two companies and founded Firstsight Vision. Initially operating only as a distributor in the UK, Firstsight Vision became the first wholly owned subsidiary of Stemmer Imaging.

Mark Williamson, corporate marketing director and current managing director at Stemmer Imaging UK, remembers: "David started Vortex Vision within a month of me starting Pinnacle Vision. We even met to discuss starting up together, but our competitive natures meant we went our own ways. However it wasn’t too long before we both realized that together we could be stronger, and when Imaging Technology was acquired by Coreco (now Teledyne DALSA) we took the step to join our companies. David was a truly inspiring leader whose humour and compassion were second to none."