Film archeologist, documentary filmmaker, and technician. Co-founder of film archive which is now part of Slovak Film Institute founded in 1963. His main domain was early photography and cinema in Austria-Hungary and Slovakia. He made around 400 documentary films about technicians, inventors, artists, as well as about history of Slovak cinema, and particularly 20-part television series Dejiny malej mechanizovanej múzy which he talked about as film version of his book Kapitolky z dejín nemého filmu na Slovensku. In 1970 Rumanovský traced lost copy of film Jánošík from 1921, and directed its reconstructed version with sound, premiered in 1975. He was president of Spolok priateľov staroslávneho Devína, and since 1996 he organised Eduard Schreiber Film Festival in Lednické Rovne .
- Books by Rumanovský
- Jozef Petzval: Život a dielo, Martin: Osveta, 1957, 61 pp. (Slovak)
- Jozef Petzval, priekopník fotografickej optiky, Bratislava: Čs. štátny film, 1960. (Slovak)
- With Ivan Stadtrucker, E.F.F. Chladný: Otec akustiky a meteoritiky, Martin: Osveta, 1961, 141 pp. (Slovak)
- Dejiny mechanizovanej múzy, TV series.
- Articles by Rumanovský
- Series of articles published in Film a divadlo, 1957-59. (Slovak)
- Kapitolky z dejín nemého filmu na Slovensku column, 1960s. (Slovak)
- Kapitolky z dejín zvukového filmu na Slovensku column, 1960s. (Slovak)
- Articles on Rumanovský
- "Ivan Rumanovský", Film.sk 5, 2009. (Slovak)