Question about 3D Cinema

[drfsupercenter]

Just wondering, is there actually a difference between "Real D" 3D, IMAX 3D, and just generic polarized 3D glasses?

A local IMAX theater here said they can't use the clip-on Real D glasses for their showing of The Hobbit, because they aren't compatible. Supposedly somebody tried to bring a pair of those to their theater and it appeared blurry.

But this is confusing to me - I thought they were all the same, just under different trade names. Is there an actual difference?

For what it's worth, the IMAX version uses only one projector, rather than two. It apparently has something to do with having two reels, one for each eye, at a specific offset from each other, but they go through the same projector.

[admin]

Both are polarized 3D systems, but RealD uses circular polarization , while IMAX 3D uses linear polarization. While both use passive glasses, they require different types of passive glasses due to this difference.

There are technical advantages and disadvantages to both types of systems, so it isn't done just for a proprietary thing (although I'm sure it comes into it).

[drfsupercenter]

Ah, OK, that makes sense.

I was assuming "polarized 3D" meant one thing in particular.

I think it has to do with the fact that normal 3D theaters use two projectors (they do, right?) but IMAX 3D just uses one projector to display both images.

[admin]

By normal if you mean RealD, then yes. There's also Dolby 3D which also uses just one projector, but it's again based on different technology than the other two, and uses glasses that are not considered disposable.

[drfsupercenter]

Never heard of Dolby 3D. But yes, I mean RealD. The RealD glasses are "disposable", but the theaters usually want to recycle them.

I usually just take them home. I've got about 10 pairs.

I was going to try to cut the lenses out and make them into clip-ons, so that I don't have to bother with wearing two pair of lenses, but that won't work with IMAX.

I don't suppose any places sell IMAX 3D glasses that were "taken" from theaters? Those COULD easily be disposable, just the IMAX I go to has a fancy non-foldable pair so they require you to give them back.

[drfsupercenter]

OK, so I just saw The Hobbit in IMAX 3D, and when I took the glasses off, it looked the same "blurry" way as regular 3D movies.

Is the difference just in how the two pictures overlap, or is it something else? It didn't look any different to me.

[admin]

All the 3D techniques look "blurry" when you don't wear the glasses, but how the glasses make them un-blurry is all different