3D projection systems have combatibility issues
 

From imdb:

'Lack of Standards Plagues 3D Digital Distributors
Since 3D digital projection systems currently installed around the world employ incompatible file formats, studios must now distribute dozens of different versions of their films, Disney's chief of production technology said Wednesday. Speaking to the ShoWest exhibitors convention in Las Vegas, Howard Lukk observed that digital projectors currently use eight different file formats. He noted that, with the addition of numerous language soundtracks, Disney is being forced to create 42 different release prints of its upcoming Meet the Robinsons for about 650 3D digital screens -- a "time-consuming and expensive" process. Lukk said that although the Society of Motion Picture and Television Engineers (SMPTE) is working on standardizing 3D digital projection systems, manufacturers of the equipment ought to come together to speed up the process.'

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