To me the screen in IMAX looks curved. Here it is flat like other regular screens but same size as IMAX. If the film being shown was shot with camera designed for IMAX, you might notice the difference. Otherwise, they are just the same.
It's similar. Large screen, amazing projector technology, great surround sound system. I haven't been able to find the exact differences, but my girlfriend and I go all the time and it's definitely worth it.
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