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3D Movies - do u need a special TV to watch in 3D?

By TorturedChaos ยท 6 replies
Apr 11, 2010
  1. Ok so I just signed the buy/sell on a house with a projector setup in it with a 4ft x 6ft screen. I don't know much of the specs on the projector, but I do know i didn't see an HDMI hookup on the back so im guess it's not HD. But could I play a 3D movie thru it on if it was setup to work with the polarized glasses and have it work? Or is there something special about 3D TV's im missing here?
  2. LookinAround

    LookinAround Ex Tech Spotter Posts: 6,491   +184

    I don't know the answer about 3D TV.. but just wanted to say "Congrats!" on the new house :)
  3. matrix86

    matrix86 TS Guru Posts: 838   +32

    Short and sweet answer:
    You will need a specialized TV. There are three different 3D formats, each needing something specific.

    More detailed to explain the short and sweet answer:
    It has to do with how the different 3d formats work. The universal 3d format is anaglyph which uses those red and blue glasses. A 3d movie has two images of everything. One for the right eye and one for the left. In anaglyph all the left eye images are one color and all the right the other color which are red and blue as well. Then the red lens blends in with the red images and only the blue can get throw. Same with the blue lens, you can only see the red images. Since this 3d format uses color all color displays can use it.

    Now with other 3d formats you have a problem. Polarized 3d that they use in the theater has one polarized light wave for the left eye images and a different polarized light wave for all right eye images. Then the lenses block one light wave but not the other, so each eye only gets one image. In theaters they may have just one projector but it has two lenses with one projecting the left eye and one the right eye images at the same time. Then you have to have a special screen that can reflect the light back with the same polarization. Televisions can't do two different light waves, just not made to do it. There are televisions that can but they have to be made to do it.

    The other 3d format is field sequential which uses shutter glasses that open and close. The one lens opens will the other one closes and they do this back and forth. When a lens opens the image for that eye will flash on screen. If the refresh rate of the television is under 100 hz (refreshing 100 time per second) then you will notice a flickering effect. Old plasma lcd television are 60 hz, rather slow. The flickering is bad. Now they can make them higher than that like 120 hz, even 600 hz. You just need a tv that can flash the images for each eye alternately at a fast enough rate and sync that up with the lenses.

    See it is not as simple as just plopping a 3d dvd in any old dvd player on any old television and watching it.
    There will be "3D capable" televisons on sale probably this year and certainly next year. They will cost about 15% more than an ordinary HD set of the same size. These new tvs will have field scanning rates of at least 200Hz (it's 50Hz for an 'ordinary' tv). Slower scan rates would make you seasick.

    In practice the polarised light system will not give you great 3D results beacuse the tv screens and scanning systems cannot generate accurate polarised light. Also, if you moved your head or sat off-centre you would loose the 3D affect. Of course it is a cheap system so Sky will transmit some sports this year to see how the public like it. They will probably charge a lot of 'subscription' fee for the privavidge too.

    The shuttered specs system pioneered by Sony and Panasonic is technically the best but requires special dynamic glasses.
    I found these answers here (I give credit where credit is due):
  4. LookinAround

    LookinAround Ex Tech Spotter Posts: 6,491   +184

    Good summary :grinthumb Thanks for that info as well
  5. matrix86

    matrix86 TS Guru Posts: 838   +32

    I had asked myself this question after watching Avatar and found that answer. It was a bit more info than I really wanted, but am glad to have learned about all of it. It looks like this 3D technology still has some kinks that need to be worked out.
  6. LookinAround

    LookinAround Ex Tech Spotter Posts: 6,491   +184

    yea, and in addition to the kinks.. I already spend too much time looking for my reading glasses when i need 'em.. not yet ready to start looking for my 3D glasses for TV as well! ;)
  7. TorturedChaos

    TorturedChaos TechSpot Chancellor Topic Starter Posts: 839   +29

    wow thanks so much for the answer! I spent some time searching online and only found bits and pieces of that info, and was just making myself confused :p.
    i guess no easy 3D with that new projector :( unless i do the annoying blue & red one....
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