Gill trained as a dancer and joined Britain's Sadler's Wells Theatre Ballet in 1946, appearing in The Sleeping Princess, which opened in Covent Garden that year.
Gill left ballet in 1955 to work in television, producing his mime play, The Way of the Cross, for the BBC before joining Associated-Rediffusion as an editor.
As a result of that year's franchise changes, he moved to Thames Television in 1968, working mainly on news and documentaries for, amongst others, the Today and This Week programmes.
Whilst at Thames, he met film historian Kevin Brownlow, with whom he was to form Photoplay Productions and work as co-director and producer on several silent film-related projects.
Brownlow and Gill formed their own company, Photoplay Productions in 1990, in order to continue their restoration work and documentaries on silent cinema.