Viswanathan appeared as the cinematographer for many films since the 1970s predominantly worked in films directed by
Rama Narayanan and also helped recommend actor
Sathyaraj for his first role in
Sattam En Kaiyil (1978). At the insistence of Kamal Haasan, he directed
Sankarlal (1981) when the film's director T. N. Balu died during the shoot. He began directing films in the 1990s, working on family dramas. In the early 2000s, he worked on several devotional films as a cinematographer and developed his knowledge of CGI and VFX related scenes. Viswanathan went on to direct
Jaganmohini (2009), a remake of the
1978 film of the same name, with
Namitha and
Nila starring. Despite creating attention prior to release, it opened to mixed reviews, with a critic citing that the film felt "dated". ==Death==