May 22, 2013 2:55pm PT by Carolyn Giardina
Christie Testing 'Quad' Projection System
The first trial site for Christie’s new “Quad” projection configuration is Hollywood’s Dolby Theatre. It was quietly installed and tested for the first time before an actual audience last week for the Los Angeles premiere of Star Trek Into Darkness in 3D, and it might become a more permanent fixture in the theater.
It’s called the Quad because the configuration uses four digital cinema projectors (in this case, four Christie CP4230 4K DLP projectors). Four projectors have been used for events such as premieres before -- particularly for filling large screens such as the 70-foot installation at the Dolby -- but making this unique is use of a newly developed lens alignment system.
With the Quad setup there are two projectors facing the screen and two others coming in at right angles to those projectors with those images bouncing off mirrors. This is effectively two joined Christie “Duo” setups (the Duo is pictured above), for which two projectors are perpendicular to each other and one of the images bounces off a mirror.
The goal of the Quad system is to bring the four lenses closer together for more accurate alignment, which is especially vital when lining up left and right eye images to produce 3D.
“When the projection lenses are further apart it’s impossible to make the pixels overlap on the screen," claimed Don Shaw, senior director of product management for Christie Entertainment Solutions. "You can align them in the center of the screen, but as you go out toward the edge of the screen, the lenses are difference distances from the screen so you get geometric irregularities and pixel misalignments."
At last week's premiere, the Quad -- for which Christie is planning a commercial release -- was used in conjunction with the Dolby 3D system.