The apprenticeship marked the beginning of a series of jobs at numerous laboratories for Biroc – which was then a required step for aspiring cinematographers.
After his time at Goldwyn Pictures, Biroc returned to New York and took a job as film printer for Famous Players–Lasky, where he was shortly after promoted to assistant cameraman.
Biroc started at RKO by serving as assistant to cinematographers Leo Tover, Robert De Grasse, and Edward Cronjager.
Two years later, he filmed the brutalities at the Dachau concentration camp in Germany while serving as captain of the sixth detachment alongside George Stevens's Special Motion Picture Coverage Unit.
Biroc also “shot film for network television early on, such as musical shorts featuring Duke Ellington, Nat King Cole, and Louis Armstrong"[2] – a feat considered rare for cameramen during the time period.
[citation needed] Biroc worked alongside four-time Oscar nominated cinematographer Joseph Walker in filming It's A Wonderful Life (1946) and achieved his first on-screen credit for his contribution.
[5] Biroc wrote an article for American Cinematographer where he explained the process behind filming the series Washington: Behind Closed Doors (1977).