He began to photograph at age thirteen in Lithuania.
Bidermanas left his native land for Paris when he was nineteen and worked as a laborer, retoucher and printer. He later ran a photographic portrait studio. In 1940 he had to hide from the Germans because he was Jewish; he took the name Izis, which he kept professionally. Izis ended up in Limoges, France, as a soldier in 1944 during the liberation of the town, where he photographed the French underground resistance fighters. These photographs were noticed by his superiors and exhibited in Limoges under the title "Ceux de Grammont." In 1949 Izis became a photo reporter at Paris-Match, where he remained until 1969.
In his work Izis strove for simplicity and an "invisible" technique. He wanted viewers to "forget the photographer" and not ask, "How did he do it?"