IMAX, 70mm, Dolby: What the Formats Actually Mean When You Buy the Ticket

Film formats (the ones shot on actual film)

• IMAX 70mm, 15-perf. The big one. A frame roughly ten times the size of standard 35mm, projected in a near-square 1.43:1 ratio that fills the wall floor to ceiling. Very few venues worldwide can run it. If a director shot on IMAX film and you have access to a true IMAX film screen, that's the ticket.
• 70mm, 5-perf. Standard large-format film, still gorgeous, wider and shorter than IMAX. Common for Tarantino and revival screenings.
• 35mm. Regular film. Increasingly a specialty format shown by repertory cinemas, and worth seeking out for the grain and the slight instability that digital removes.
• VistaVision. A 1950s format running 35mm horizontally for a bigger frame, revived recently by directors chasing a specific texture.

Digital formats

• Digital IMAX. Uses the branding and often a large screen, but not the 1.43:1 film frame. Sometimes excellent, sometimes a normal auditorium with a logo. Worth checking which one your local site actually has.
• Dolby Cinema. Laser projection, extremely deep blacks, aggressive sound. The best digital experience in most cities.
• 4DX and similar. Moving seats, water sprays. A theme park ride. Fine for a franchise sequel, wrong for anything with dialogue.

How to decide in ten seconds

Ask two questions: what was this shot on, and what's within reach? A film shot on IMAX cameras deserves the largest film screen you can get to. A quiet drama shot digitally gains nothing from a premium surcharge and loses nothing in a decent standard room.

The single biggest quality variable is not the format. It's whether the venue maintains its projector and keeps the lights down. A well-run standard screen beats a badly run premium one every time.

Aspect ratio changes mid-film are usually intentional. If the image expands when the movie hits a big sequence, that's the director telling you the format is part of the point.