realD 3D vs Imax3D vs HFR3D Questions?

[PatrickFaith]

Hate to bug the experts, but I know you guys read this forum ... so ... I wanted to buy glasses for the new hobbit movie, but i got confused. Since I worked on 3D optics over 30 years ago, I figured if i'm confused a lot of other people are confused. Here's my list of basic questions:

Q. What is the optical difference between the IMAX3D glasses and realD 3D glasses?
A. RealD uses circular polarization while IMAX uses linear. This means if the glasses in IMAX theaters are more sensitive to being tilted/not exactly straight on your nose. So if you where glasses, make sure the lenses are completely flat on your bridge or you will see double image. Also means that the lenses are completely different and are not interchangeable between theaters types. There is also cross talk on circular polarization, but you can't do anything about that as a movie goer.

Q. Are realD 3D glasses the ones you need to get to watch 3D in the theater if your not in a IMAX 3D theater?
A. yes ... realD for "normal" 3D (aside from a small set of theaters that are dolby 3d, but you didn't ask about that).

Q. Is HFR 3D (48 fps) only in the "normal" realD 3D theater rooms?
A. No, both imax and realD have both 24 and 48 fps modes.

Q. I don't need different glasses for HFR, right ? (i.e. all i need is either a IMAX 3D or realD glasses)
A. Yes, neither lenses are "active" so frame rate doesn't matter on the glasses that you use in the theaters (though it does for home theater).

Q. Is HFR realD ever shown inside a "imax" theater room? (sometimes i see a movie in a IMAX room, but it is low quality like a normal film)
A. Very rarely.

Q. IMAX 3D is not shown at 48 fps (i need to go to a realD smaller room to see 48 fps)?
A. IMAX 3D HFR is supported at some theaters for the hobbit, though many will show at 24 fps, you need to check internet listing or ask at the theater.

I checked out a bunch of sites, i couldn't find any "practical" information that explains exactly what someone needs to buy for optimized HFR viewing. Much thanks for the answers

[Edit ... adding answers, if is a "better" answer, please comment]

 

[Jason Rudd]

This comment isn't directly answering your questions, but to explain the differences in the polarizing technologies, you'll notice that Real 3D uses a single projector, whereas IMAX uses two Left / Right projectors for both their digital and film screens. Because of that IMAX screens are much brighter when wearing glasses, and a much better image IMO.

 

[PatrickFaith]

This comment isn't directly answering your questions, but to explain the differences in the polarizing technologies, you'll notice that Real 3D uses a single projector, whereas IMAX uses two Left / Right projectors for both their digital and film screens. Because of that IMAX screens are much brighter when wearing glasses, and a much better image IMO.

Thanks, didn't know that, that makes sense ... it's like engineers are "trading" more light vs invariant head angle, between the two methods. Can you confirm that many of the IMAX 3D screens can also be run at 48 fps (that answer was "not positive", it seems like there is a firmware or something upgrade to get 48 fps going and that hasn't been done everywhere)? I also read that the 3D effect is better when the aspect ratio was closer to the IMAX 4/3 but i'm not sure what aspect ratio they will be using for the IMAX 3D HFR.

 

[Jason Rudd]

I'm not sure what aspect ratio they'll be using - progbably 1.9 or 2:1. You're right, they're trying to put in revisions to the software / projector servers to enable 48FPS though I don't know how many. I hope that they'll be a lot of screens available for this too! Of course the film projectors will still be at 24 FPS.

 

[Ketch Rossi]

To over simplify things, they are the Polarizer, Active, and the old Bicolor glasses, then there are variation within them.

I have purchased several pairs of Oakley Passive 3D glasses, and use them in every 3D showing, never daring to put that crappy thin scratched dirty plastic 3D glasses they give you, and they so far have worked every were, it will be the same with HFR 3D showing, unless of course they are showing via Active Glasses, then you are stuck to each particular exhibitor, same as you do on your home entertainment system, were Sony 3D Active glasses can't view images on a Samsung 3D TV, or viceversa.

We really need only "ONE" or two options at most, Active and Polarized, were Bicolor it is still needed for computers, unless hooked up to your 3D TV of choice.

 

[Tom Tomlinson]

I'm not sure what aspect ratio they'll be using - progbably 1.9 or 2:1 .

Don't you think it will be one aspect ratio in the theater--scope----and possibly more on home video.

 

[PatrickFaith]

... I have purchased several pairs of Oakley Passive 3D glasses, and use them in every 3D showing, never daring to put that crappy thin scratched dirty plastic 3D glasses they give you, and they so far have worked every were, it will be the same with HFR 3D showing, unless of course they are showing via Active Glasses, then you are stuck to each particular exhibitor, same as you do on your home entertainment system, were Sony 3D Active glasses can't view images on a Samsung 3D TV, or viceversa.
....

Good call Ketch, I am looking at the "LIMITED EDITION THE HOBBIT: AN UNEXPECTED JOURNEY 3D GASCAN EYEWEAR" at oakley : http://http://www.oakley.com/products/7091/26944 . My question is, will that work for both realD and imax 3d (i.e. do the lenses do both linear and circular polarization)?

EDIT ... looks like the glasses are only for the REALD theaters and will not work with the imax3d ... http://www.oakley.com/innovation/op...t-packaging-_-innovation-_-packaging-_-hdo-3d ... this type of info seems awfully hard to find. I think ketch is right, the industry needs to standardize on a single type of passive lens.