Cillian Murphy and Robert Downey Jr. in “Oppenheimer”.Photo:Melinda Sue Gordon/Universal Pictures

Cillian Murphy is J. Robert Oppenheimer and Robert Downey Jr is Lewis Strauss in OPPENHEIMER, written, produced, and directed by Christopher Nolan.

Melinda Sue Gordon/Universal Pictures

Christopher Nolanknows some of the dialogue inOppenheimeris difficult to make out at times.

The three-hour historical drama — which has so far madeover $500 million at the worldwide box officesince debuting alongsideBarbieon July 21 — has some moviegoers scratching their heads, unable to hear moments of dialogue.

Director Nolan, 53, recently toldInsiderthis is because he doesn’t have his actors return to the recording booth in post-production to recapture dialogue to make things clearer. This common filmmaking step is called automated dialogue replacement, or ADR.

“I like to use the performance that was given in the moment rather than the actor re-voice it later, which is an artistic choice that some people disagree with, and that’s their right,” he told the outlet.

Christopher Nolan.Laurent VU/SIPA/Shutterstock

Christopher Nolan, Oppenheimer Premiere

Laurent VU/SIPA/Shutterstock

Additionally, the IMAX cameras Nolan uses for his movies can be noisy, interfering with quieter scenes.

“There are certain mechanical improvements. And actually, IMAX is building new cameras right now which are going to be even quieter,” he told Insider. “But the real breakthrough is in software technology that allows you to filter out the camera noise.”

“That has improved massively in the 15 or so years that I’ve been using these cameras,” said Nolan, “which opens up for you to do more intimate scenes that you would not have been able to do in the past.”

Cillian Murphy in “Oppenheimer”.Melinda Sue Gordon/Universal Pictures

Cillian Murphy is J. Robert Oppenheimer in OPPENHEIMER, written, produced, and directed by Christopher Nolan.

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Nolan often fields critiques about the sound design of his films making dialogue inaudible. There were reactions to Tom Hardy’s Bane being unintelligiblethroughout 2012’sThe Dark Knight Rises, and Nolan previously said 2014’sInterstellarfaced similar complaints.

“I actually got calls from other filmmakers who would say, ‘I just saw your film, and the dialogue is inaudible.’ Some people thought maybe the music’s too loud, but the truth was it was kind of the whole enchilada of how we had chosen to mix it," he said at the time.

Added Nolan, “I was a little shocked to realize how conservative people are when it comes to sound. Because you can make a film that looks like anything, you can shoot on your iPhone, no one’s going to complain. But if you mix the sound a certain way, or if you use certain sub-frequencies, people get up in arms.”

Interstellarended up with nominations in both the Sound Mixing and Sound Editing categories at the Oscars, as well as Production Design and Original Score. It won Visual Effects that year.

Oppenheimeris in theaters now.

source: people.com