LOS ANGELES — On Nov. 23, 1963, the day after President John F. Kennedy was shot, NBC News producer and director Frederic Rheinstein was in a remote broadcast truck outside Dallas’ city hall with his crew. Suddenly, a stranger poked his head through an open window.

“He caused me to look up because in putting his head through the window he put aside a curtain allowing light into the otherwise darkened truck,” Rheinstein later said in testimony before the Warren Commission, which looked into the assassination. Rheinstein said he didn’t know the man’s name at the time, “but it was an irritant, so his face became fixed.”

The next day, the whole world knew of the man — Jack Ruby. Rheinstein’s cameras were there when Ruby fatally shot Lee Harvey Oswald, Kennedy’s assassin. Unlike rival CBS, Rheinstein caught this moment in 20th century history in real time. “We did have a camera live, and I was able to persuade our leaders in New York to cut to us,” Rheinstein said in 2012 on a panel discussing coverage of the event.

Rheinstein, 86, who went on to direct coverage of other major news events and later started a prominent TV and film post-production house, died Dec. 22 at his home in Los Angeles.