What sets digital 3-D apart from traditional 3-D films?

Modern 3D animated films, such as Meet the Robinsons, utilize techniques like shadowing, texture mapping, object scaling, and various other methods to replicate a three-dimensional setting. Explore more about the filmmaking process. Photo courtesy Walt Disney/Buena Vista Pictures

Contemporary animated films excel at simulating three-dimensional worlds. Movies like "The Incredibles," "Cars," and the "Shrek" series feature characters that appear as tangible entities, seamlessly interacting with their environments. Achieving this realism requires extensive effort and a deep understanding of visual perception. Filmmakers often create physical models, or maquettes, to visualize how a 3-D character would navigate a three-dimensional space.

In recent years, filmmakers have pushed the boundaries of recreating three-dimensional environments on screen. Through digital 3-D, animators can trick your eyes and brain into perceiving depth on a 2-D screen, creating the illusion of a three-dimensional world. The effect is akin to gazing through a window into a tangible, lifelike space or feeling as though elements of the scene are present in the theater. Though reminiscent of older 3-D techniques, the technology is far more sophisticated.

Both classic and modern 3-D films exploit the intricacies of human vision to craft immersive, expansive scenes or objects that appear to leap off the screen. Humans possess binocular vision—each eye captures a slightly different image, and the brain merges them into a cohesive picture. The brain interprets the angle difference, known as parallax

, to gauge depth. This is why individuals with vision loss in one eye often struggle with depth perception.

Traditional 3-D films employed anaglyph imagery to leverage binocular vision and parallax effects. These images combine two color layers within a single film strip, projected from one projector. One layer is primarily red, while the other is mainly blue or green. Viewers wear 3-D glasses with one red lens and one blue or green lens, which filter the image so each eye sees a different color layer. The brain merges these layers into a single three-dimensional image. However, the color-filtering process often results in inaccurate colors and can cause headaches, eye strain, or nausea for some viewers.

For additional details on 3-D imaging, visit the next page. 

Digital 3-D Imaging

As explained by director Steve Anderson and 3-D supervisor Kyle Odermatt, the scene in "Meet the Robinsons" where Lewis arrives in the future showcases the film's most extensive use of three-dimensional depth. Photo courtesy Walt Disney/Buena Vista Pictures

Digital 3-D also manipulates vision through imagery but relies on polarization instead of color filtering. Polarized lenses permit only light waves aligned in specific directions to pass through. In digital 3-D glasses, each lens has a distinct polarization—some differ by 90 degrees, while others use circular polarization. The screen is specially designed to preserve polarization when reflecting light from projectors. Without glasses, the movie appears normal but blurry, unlike the red-and-green mesh of older 3-D films.

Digital 3-D films utilize one or two digital projectors to display images on the screen. In dual-projector setups, one projector caters to the left eye, while the other serves the right. Each image's light is polarized to align with the corresponding lens. Single-projector systems often employ a polarization switch attached to the projector lens, which alternates between images for each eye rapidly. This creates a seamless, three-dimensional effect as the brain merges the frames. Some systems use active glasses synchronized with projectors via radio waves, though these are bulkier and costlier than standard polarized glasses.

Unlike anaglyph technology, this method preserves color accuracy and minimizes adverse effects like headaches. As a result, filmmakers are increasingly designing movies with 3-D projection in mind. For instance, "Meet the Robinsons," released on March 30, uses digital 3-D to enhance storytelling rather than relying on flashy visuals. Director Steve Anderson emphasizes that the focus was on narrative depth, scaling back 3-D effects during emotional scenes and amplifying them during action sequences, such as the dinosaur chase.

The future of this technology remains uncertain, but 3-D screenings of children's movies often yield higher box office returns. This trend suggests that more films may incorporate 3-D projection as the industry evolves.