Wanting to know more about the B&W scenes in Zone of Interest, I stumbled across this magnificent article about the film: Viewing the Ob-scene: On Jonathan Glazer’s “The Zone of Interest”

These scenes are shot without lighting and in infrared, so the girl’s body appears as white against the sheer black of her surroundings. It’s a startling, uncanny reversal of the daytime scenes, and the only act of compassion we witness in the film, which must necessarily take place out of sight.