His brother Robert Asher was a film and TV director with whom he worked on several occasions.

He began his cinematic career as a camera operator, and made his first film as cinematographer or "lighting cameraman" on The Magic Bow (1946).

He was the director of photography on several of the colour Hammer horror films including Dracula (1958), The Revenge of Frankenstein (1958), The Hound of the Baskervilles (1959), The Mummy (1959), The Two Faces of Dr. Jekyll (1960) and The Brides of Dracula (1960) as well as some of the company’s moody monochrome thrillers like The Camp on Blood Island and The Snorkel (both 1958).

[2] Director Terence Fisher said of him, "Jack Asher had a very distinctive style of lighting, which was quite different from Arthur Grant's...(Who) had a more realistic approach to the situation.

"[3] Asher's non-Hammer films included The Good Die Young (1954) and Reach for the Sky (1956).