All of the new 3-D blockbusters hitting the theaters use digital 3-D effects combined with polarizing lenses to trick the eye into seeing three-dimensional images. Headquartered in Beverly Hills, RealD is the market leader in digital 3-D technology. Erica Taub, reporter with the New York Times, reported that nearly 4 million RealD glasses were worn on the opening weekend for "Avatar." RealD uses circular polarization, a passive technique that filters light in a circular pattern. The lenses on the RealD glasses have filters that move the light in a clockwise direction for the right eye and counter clockwise for the left.
IMAX 3-D also uses polarization to create the 3-D effect; however, it utilizes linear polarization instead of circular. The difference is how the light from the projector is filtered to each eye. In order to get the maximum effect of the IMAX 3-D imagery, the viewer must keep his head level to avoid bleed-over to the opposite channel.
In order to show 3-D movies at their best, multiplex theaters have had to make modifications to the the auditoriums slated to show 3-D films. RealD films require a special silver screen that retains the polarization effect and reflects it back to the audience. IMAX 3-D movies require a much larger screen and two separate rolls of film that are run simultaneously. All multiplexes showing 3-D movies need to have a ready supply of viewing glasses; however, a theater showing both RealD and IMAX 3-D movies will need to supply two different types of viewing glasses.
IMAX 3-D films shown in retrofitted multiplexes are not true representations of the famed, IMAX Experience. Classic IMAX Theaters are specially designed to deliver the highest quality video and sound, while the retrofitted multiplexes lack many of the IMAX company's specialized technology. However, in September 2009, The Neilsen Company, in cooperation with the IMAX company, conducted a survey examining audience satisfaction of the IMAX Experience in both classic and multiplex design theaters. The survey concluded that there was no meaningful difference between audience satisfaction with either IMAX Experience, and audience members generally preferred the IMAX format over all.
When it comes down to which format to chose, personal preference and cost tend to be the deciding factors. Ticket prices for both 3-D formats are more expensive than ticket prices for standard movies. However, the cost to see a movie in IMAX 3-D is greater than seeing a movie in RealD. When it comes to the quality of one format over the other, both RealD and IMAX boast having the best 3-D technology, but most movie goers have their own opinions as to which format is better.