Oppenheimer's VFX supervisor sets record straight on use of CGI in the movie

Oppenheimer's VFX supervisor has finally set the record straight on the use of CGI in the movie.

Since the film's release last month, cinema-goers have been witnessing Peaky Blinders' Cillian Murphy take centre stage with his remarkable portrayal of theoretical physicist J. Robert Oppenheimer, who devised the world's first atomic bomb during WWII.

The three-hour film is director Christopher Nolan's first ever biographical drama, which also stars the likes of Robert Downey Jr., Matt Damon and Emily Blunt, among many others.

Oppenheimer has promised to be a nuclear hit from the get-go as Nolan’s movie has grossed $718 million at the global box office.

It is now the fourth most successful movie of Nolan’s career, and the fourth biggest film of the year.

Besides the star-studded line-up and the storyline, what hooked viewers in was reports that the film was made without CGI - and without detonating an actual bomb, of course.

Universal Pictures

Explaining how they detonated a fake atomic bomb, director of photography, Hoyte van Hoytema, previously told Variety: "Obviously, we couldn’t make an explosion the size of the actual explosion so we used trickery.

“We had moulded metallic balloons which were lit up from the inside.

“We had things slamming and smashing into one another such as ping-pong balls, or just had objects spinning.”

He added: “We had long shutter speeds, short shutter speeds, wide negative colour, negative overexposure, underexposure.

"It was like a giant playground for all of us.”

However, Oppenheimer’s Oscar-winning VFX supervisor Andrew Jackson has clarified the use of CGI in the film.

Universal Pictures

"Some people have picked that up and taken it to mean that there are no visual effects, which is clearly not true," Jackson told the Hollywood Reporter.

He explained that 'visual effects can encompass a whole lot of things', including CGI.

But Jackson did firm up that '[Nolan] didn’t want use any CG simulations of a nuclear explosion'.

"He wanted to be in that sort of language of the era of the film … using practical filmed elements to tell that story," Jackson added.

"They used four 44 gallon drums of fuel and then some high explosives under that, which sets the fuel alight and launches it into the air.

"We had some with really close-up detail of the burning explosion.

"We had a lot of material that we could layer up and build into something that had the appearance of something much bigger."