After dropping out of medical school for having spent too much time at the Cinémathèque Française, Denis Lenoir decided to make a profession out of his passion and joined École Vaugirard in Paris, France, where later he also studied Art History at École du Louvre. After film school, he became a camera assistant with French cinematographers Bernard Lutic and Ricardo Aronovich. Not very good at this craft, Lenoir decided at age 27 to become a lighting cameraman. His credits include more than 45 feature films, as well as TV pilots and films for TV, commercials and music videos.

Lenoir has been granted in 2002 with an ASC Award for the miniseries Uprising and the Camerimage Film Festival “Bronze Frog” for Demonlover. In 2013 he received  the AFC Caméflex at the Amiens Film Festival and in 2024 he received with Yorick Le Saux the prix AFC for the series Irma Vep. A co-founder of  the Association Française des Directeurs de la Photographie Cinematographique, the AFC, he has also been a member of the American Society of Cinematographers, the ASC, since 2001. In 2006 he was invited to join the Academy of Motion Picture Arts and Sciences.

A recognized still photographer and the author of a book on film director John Cassavetes, Lenoir is an officer in the Ordre National du Mérite. His recent credits include the music video DNA for artist Kendrick Lamar as well as features and series Wasp Network and Irma Vep by Olivier Assayas, Still Alice (staring Julianne Moore, 2015 Oscar for Best Actress) by Richard Glatzer and Wash Westmoreland and Things to Come, Bergman Island and One Fine Morning by Mia Hansen-Løve.

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