> Having to recline and look up at the screen was annoying, and the size was gratuitous with most of it wasted to peripheral vision.
The first feature is a function of sitting to close to the screen, and isn't specific to IMAX format. The second is by design -- a major point of large-format cinema screens like IMAX is to provide a more immersive experience by making it so that, in shots where there is a strong central focus, even the non-focal parts of your vision field are occupied by the movie screen rather than (usually, just black) background from the theater, and, second, enabling shots that are composed so as to invite audience members to not just focus near center, but to look around the screen (this second feature isn't taken advantage of in films not designed for large-format screens, but major films now generally are made in a large-format aware manner.)
The first feature is a function of sitting to close to the screen, and isn't specific to IMAX format. The second is by design -- a major point of large-format cinema screens like IMAX is to provide a more immersive experience by making it so that, in shots where there is a strong central focus, even the non-focal parts of your vision field are occupied by the movie screen rather than (usually, just black) background from the theater, and, second, enabling shots that are composed so as to invite audience members to not just focus near center, but to look around the screen (this second feature isn't taken advantage of in films not designed for large-format screens, but major films now generally are made in a large-format aware manner.)