Ottomar Domnick, born April 20, 1907, in Greifswald, as the son of a staunch Prussian academic family, at first became a mechanic after finishing school. After his apprenticeship, Domnick qualified for higher education and studied medicine from 1927 to 1933. He then became a medical specialist for neurology and psychiatry at the Frankfurt university hospital. In Frankfurt, Domnick also met his colleague Margarete Gerhardt who became his wife in 1938. In the same year, Domnick opened his own medical practice.

Shortly after the beginning of World War II, Domnick was drafted for military service. When the war ended, Domnick was captured by the Russians as a prisoner of war but managed to flee in June of 1945. Back in Stuttgart, Domnick opened up medical practice together with his wife and expanded it to a psychiatric private clinic in 1951.

During that time, Domnick also began to socialise with the Stuttgart art scene and became friends with several renowned artists, philosophers, art historians, and collectors. Domnick then, too, collected a substantial number of abstract paintings. With his publications and work as a curator, Domnick developed into one of the most important figures of the post-war art scene in Germany. To make abstract painting more accessible to a general public, Domnick made the short film "Neue Kunst – neues Sehen" in 1950 and the portrait film "Willi Baumeister" in 1954.

More and more disappointed by the developments in painting, Domnick successfully turned his focus to the cinema. In 1957, his first feature film "Jonas" premiered at the Berlinale, received some rare reviews, and won German film awards for cinematography, music, and best young actors. When his second feature film "Gino" flopped, Domnick made three unconventional experimental films, "Ohne Datum", "N.N.", and "Augenblicke", that deal with social and political problems like the nuclear war, social isolation, and ecological destruction.

From 1967 on, Domnick showcased his art collection in a private museum. He offered several art and experimental film awards but did not make any films himself except for his self-portrait "Domnick über Domnick".

On June 14, 1989, Ottomar Domnick died in Nürtingen-Oberensingen near Stuttgart.