Dolby Digital 3D at home?

[rolypolyman]

I'm not sure whether this is an encoding, hardware, or general question so I'll just post it here.

I am curious whether anyone here has managed to experiment with Dolby Digital 3D. I remember being amazed by this technology a couple of years ago, and seeing no homebrew topics about it anywhere, I forgot about it. Last night we took our kid to see Puss N Boots in 3D, which got me to thinking about it, but once again, there's pretty much nothing in terms of homebrew on the forums.

I know 3DTV may be around the corner, but it's not really here yet, and traditional anaglyph sucks and polarization technologies (Real3D, etc) are dealbreakers in the home theater due to the screen expense & dual projector requirements.

Dolby Digital 3D simply uses glasses with special bandpass filters to extract different parts of the color spectrum, which the eye them composites into what seems like a color image. From what I can tell this is a rather simple technology which in principle should require no special hardware aside from the glasses. I don't see any reason why this format would require color wheels or dual projectors if all the colors being projected are in the ballpark.

So my questions are along the lines of: what is your take on this with regard to home theaters or video encoding? Is it possible to get this format on BluRay or DVD? All I see anywhere is traditional anaglyph. Can I encode my dual-camera home movies to this format using some kind of AviSynth script?

[kakomu]

I imagine one of the big problems with Dolby 3D at home would have to be the fact that color reproduction by TVs and projectors isn't consistent. This can be a problem when the technology is based on a pair of glasses with expensive, finely tuned filters.

[rolypolyman]

Well, see, that's the thing -- color fidelity shouldn't be that much of an issue because Dolby has a vested interest in making the color bands as wide as possible to accommodate more shades and hues. Plus there's only two channels involved. I would think consumer equipment would be well within the range needed to produce decent images... but of course I won't know for sure until I get the glasses.

[kieranrk]

http://www.avsforum.com/avs-vb/showthread.php?t=1325342

[Asmodian]

Well, see, that's the thing -- color fidelity shouldn't be that much of an issue because Dolby has a vested interest in making the color bands as wide as possible to accommodate more shades and hues. Plus there's only two channels involved. I would think consumer equipment would be well within the range needed to produce decent images... but of course I won't know for sure until I get the glasses.

It doesn't seem to work quite like that, it still needs two projectors. It would be best with two laser displays using a slightly different wavelength for red, green, and blue on each display. There is no limit on the range of colors displayed to either eye. Since humans only see red, green, and blue, and derive a sense of color from the relative brightness of each you block the specific red/green/blue wavelength used for the other eye. It is just like rotational polarization but it should be easier to get higher brightness as you don't need to have a polarized light source or polarized glasses.

The diy method is to use the lenses from a pair of glasses to filter the correct set of wavelengths for each eye using two projectors. The problem with this is that the relative brightness of red/green/blue in the light source can be different in the two different sets of wavelengths, giving slightly different colors in each eye.

http://www.avsforum.com/avs-vb/showthread.php?t=1325342

This is a very cool idea, much easier than getting a very clear but very strong polorizing film. :eek: