Mainly because the IMAX camera is REALLY loud. This thing makes so much noise that any dialogue spoken near it has to re-dubbed afterwards in post-production. Ambient sounds too. That and most theaters do not have the sheer film platter size to accommodate the massive amount of film an IMAX movie requires.

"But aren't there digital IMAX cameras which don't even use film?". The answer is yes, but their image quality can't really hold a candle to the 70mm IMAX film negative, so they're not used much even in short IMAX movies,the kind of which you see at science museums and so on. And have you noted not many of those are over 20 min or so? Again, the platter size. It takes up a lot of space even in a dedicated IMAX theater. That's why there are no feature-length IMAX films yet.

"But TRON was shown at a lot of IMAX theaters!" Yes, it was, and it looked great, but most of it was shot on ordinary digital cameras and then processed to look good at IMAX size. Even Lucas says this process is one that gives a good image, so there you go. The action sequences such as the light cycle battle were seen as digital, IMAX-format sequences, though shown from a digital projector, so they required no upgrade processing in post.

I think it was kind of col to find out that 70 mm IMAX film is nowhere near as sharp as any other format even today, digital or not.

Hope I got that right. Most info via Wikipedia.

I agree completely and have already read a few of those. Thanks. These theaters are indeed IMAX-certified and equipped, but the screen is the same frigging size-or just barely bigger-than what you'd get in a normal theater with a typical screen. I have no problem calling it LieMax either. Too bad that describes the only so-called IMAX screen in my area as well.

I do find it very surprising to know that the IMAX film negative is still about the highest resolutkion way to get anything on film and show it in a theater even in this digital age of ours. Almost makes me wonder why there isn't a truly IMAX-resolution digital motion picture camera yet, but that can't be too far off. You could do a LOT more with it than an ordinary IMAX camera, because an IMAX camera is, as I said, very loud, and they're tough to get ready for a shot. A typical shot setup takes 45 minutes, and the camera is way too heavy and sizeable to be easily moved around much.

I don't know... digital IMAX looks pretty good to me. I saw Tron: Legacy 3-D in a 70mm IMAX theater and in digital IMAX theaters, and the digital ones usually looked better, imo. For the 70mm screen -- assuming they were using 70mm film? -- it was dimmer and there was a discernable flicker (the framerate wasn't as smooth). Was Tron Legacy 3-D released in 70mm at all? If not, then maybe the 70mm-capable theater was showing it in digital and because their facility is older maybe their digital just can't compete very well with newer digital LieMAX auditoriums? (Update: Just re-read the original post. I guess you're saying T:L wasn't at all created using 70mm film? Bummer.)

Visuals aside, LieMAX auditoriums I've gone to seem to have noticeably larger screens than normal theaters, and they crank the audio! I hate it when audio is whisper quiet, especially in movies that have a lot of dialogue. Because of that, I've enjoyed my LieMAX experiences.

That said, I can't wait for further improvements in the digital IMAX world -- especially if it means better visuals.

yeah, I have to say that from a cinematic quality standpoint, they got everything about T:L right. The 3D. The digital cameras. And at least some of it in IMAX.

The first time I went to see a movie in a regular cineplex which I thought was going to be IMAX, I walked in, looked at the screen and said WTF? i almost had to ask the manager if I was in the right theater because that was NOT an IMAX screen. It was apparently my first confrontation with a LieMAX screen. True, I am sure the theater met all other IMAX-specific requirements like having a gimbaled floor, proper viewing angles, speaker placements etc. But unless you walk into the theater and are impressed by the screen even before the movie begins, it's NOT IMAX.

The sound was way good though. I almost got up and jammed when Sam and Gem walked into the EOL club, which is, as far as I am concerned, the coolest entrance scene in cinematic history, even if it is rather short.

I was impressed to find out from the tour of the IMAX corp headquarters that two tech-review boobs on YT managed to get that from the IMAX HQ, techs monitor or are capable of the live monitoring and quality control of every single last IMAX movie playing anywhere in the world. LieMAX aside, there is some impressive state-of-the-art stuff going on behind the scenes with IMAX and it's theaters. It's a lot more than just 70mm film and a big-assed screen.