From a Canadian Expo '67 experiment to the 70mm film stock Christopher Nolan refuses to leave. The most-prestige film format in modern cinema.
IMAX is, by significant margin, the most-discussed film exhibition format of the past twenty-five years. The brand has become shorthand for premium theatrical presentation. What's less commonly understood is what the format actually is — and how much of what is sold as 'IMAX' in 2026 is, in fact, not the same technology that Christopher Nolan, Denis Villeneuve, and a few other directors fight to deliver on.
This essay traces the format from origin to current state.
IMAX was developed by four Canadian engineers — Graeme Ferguson, Roman Kroitor, Robert Kerr, and William Shaw — for Expo 67 in Montreal. The first IMAX-format film, Tiger Child (1970), screened at the Fuji Pavilion at Expo 70 in Osaka. The format used a 70mm film stock with a 15-perforation horizontal frame size — significantly larger than the 35mm 4-perforation vertical frame that was standard cinema, and roughly nine times the surface area per frame.
The larger frame produced significantly more visual information per second. The format was, throughout the 1970s and 1980s, used almost exclusively for short documentary films exhibited at science museums and theme parks. The screens were larger than conventional cinemas (typically 50-80 feet tall, compared to a standard 30-foot cinema screen). The exhibition was a specialised vertical, not a mainstream theatrical format.
The first mainstream feature film shot partially in IMAX 70mm was Christopher Nolan's The Dark Knight (2008). Nolan shot four sequences — the opening Joker bank robbery, the Hong Kong skyscraper jump, the chase sequence with the truck flip, the conclusion — in 15-perf 70mm IMAX. The rest of the film was shot in conventional 35mm anamorphic. The IMAX footage was, in mixed-format theatrical presentations, projected at the larger aspect ratio, with the picture filling more of the screen than the rest of the film.
The Dark Knight's commercial success — over $1bn worldwide — established that audiences would respond to genuine 70mm IMAX presentation. Nolan extended the approach: Inception (2010, partial IMAX), The Dark Knight Rises (2012, 72 minutes in IMAX), Interstellar (2014, 65 minutes), Dunkirk (2017, 75 minutes), Tenet (2020, partial), Oppenheimer (2023, the first feature film shot mostly in IMAX 70mm).
Other directors have followed. Denis Villeneuve shot Dune (2021) and Dune: Part Two (2024) partly in IMAX 65mm. Brady Corbet's The Brutalist (2024) used VistaVision, a related large-format film stock. The 70mm theatrical revival is, in some sense, the project of a small group of working directors who have refused to abandon film as a working format.
Most contemporary IMAX exhibition is not 70mm. The format that most cinemas market as 'IMAX' is, in fact, digital IMAX — a 2K or 4K digital projection system using two projectors for increased brightness, typically on screens that are larger than standard cinema screens but smaller than the original 70mm IMAX dome screens.
Digital IMAX produces approximately one-quarter of the resolution of 70mm IMAX. The aspect ratio is the same (1.43:1 expanded; 1.90:1 standard digital IMAX), but the resolution is significantly lower. The result is that 'seeing a film in IMAX' in 2026 can mean either: the genuine 15-perf 70mm experience that Christopher Nolan is delivering Oppenheimer in, or the digital-IMAX experience that most multiplexes are providing.
This is not, on Nolan's accusation, an accident. The IMAX Corporation, since its 2007 transition to digital technology, has progressively focused on the digital exhibition model because it is significantly cheaper to install and operate. The number of cinemas worldwide that can project 15-perf 70mm IMAX is now under fifty. Oppenheimer's 70mm release reportedly required IMAX Corporation to refurbish projection equipment that had been dormant for years.
The 15-perf 70mm IMAX presentation is, when it works, visibly different from any other theatrical format. The image resolution is high enough that audiences can read individual textures — the weave of a fabric, the stubble on a face, the grain in a wall surface — at distances that conventional cinema cannot deliver. The brightness is significantly higher. The aspect ratio expands to fill more of the screen than the standard cinema format.
The downside is that the format is operationally expensive. The cameras are loud (the IMAX 70mm cameras Nolan uses are reportedly so loud that on-set audio recording is impractical; almost all Nolan film dialogue is ADR-recorded in post). The film stock is expensive (a 1,000-foot magazine holds approximately ninety seconds of footage). The processing infrastructure is limited (fewer than five laboratories worldwide can process 70mm IMAX negative).
The 70mm IMAX format is unlikely to expand much beyond the small group of directors currently committed to it. The economics are punishing; the exhibition footprint is small. What will probably continue is the bifurcation between the genuine large-format experience available in a small number of premium-format cinemas and the broader 'IMAX-branded' digital experience available in most multiplexes.
The implication for audiences is that 'IMAX' as a brand no longer specifies a particular experience. To watch Oppenheimer in the format Nolan shot it in, the viewer needs to find one of the roughly thirty cinemas worldwide projecting 15-perf 70mm IMAX. Anywhere else, the film is being shown in a downsampled version of itself. The directors who care about the format have, increasingly, made this fact explicit in their press tours. Whether the audience cares enough to seek out the genuine presentation remains to be seen.