Christopher Nolan wants you to watch The Odyssey at an IMAX 70mm cinema. That's not surprising given the lengths he went to in order to film his interpretation of Homer's epic in that format, but the heavy plugging for IMAX is stirring debate.
If you watch The Odyssey trailer on YouTube, you'll see it in something close to the traditional 35mm CinemaScope aspect ratio of 2.39:1. That's how most people will see the movie in cinemas. But if you visit the film's website, you can toggle through no fewer than six different screen formats, from IMAX 70mm and IMAX 1.90:1 to Dolby Vision 1.85:1.