Over the past several years, KÀ has been thrilling audiences over and over again on the famous Las Vegas Strip. With a void as a performance space, it takes quite a bit of technological magic to fill that space. Combining scenic elements with lighting, sound, and projection, Cirque du Soleil has created a world for their performers to tell the story of two Imperial Twins separated by war and their journey to re-unite. As with every great story, KÀ as a production has undergone revisions to keep it contemporary with today’s expectations. The projection system, created by Holger Förterer, was groundbreaking at the time of the creation of the show. With the cinematic concept in mind, it was necessary to create a new way of projecting scenery. Although the system has been recently updated, as with any good story, we must start at the beginning. In 2002, Guy Laliberte (Founder of Cirque du Soleil) and Guy Caron (Director of Creation) conceived a new production at the MGM Grand. They brought in a world-class team under the direction of Creator and Director Robert Lepage. What they created was epic. To bring all the elements of their tale to life required a new way of thinking. Instead of starting with a stage, they decided to start with a void. This allows the ultimate flexibility in creating their world. The perimeter of the performance space has five stage lifts in addition to a network of catwalks in the house and behind the proscenium. The remainder is filled with two specially designed stages. Upstage sits the Tatami Deck, a 75,000 pound structure that travels downstage 46 feet over the void like a giant drawer. The second stage is the Sand Cliff Deck (SCD), which is also a critical part of the projection system. This stage weighs in at 80,000 pounds, measuring 25 feet by 50 feet and 6 feet thick. It can simultaneously lift 66 feet, rotate 360 degrees continuously, and tilt 100 degrees. It is supported by a hydraulic gantry crane, which combined with the deck is a massive 280,000 pound system. It contains 80 pegs which protrude from the surface. Yet, lying underneath the thin skin of this massive structure is a network of capacitive tiles, making the surface essentially a giant touch screen. This is but one element of the interactive projection system. Originally, to fill this space with imagery, the creative team chose three SXGA lumen DLP projectors stacked in the back of house. Their combined power (17,500 lumens each) was necessary to provide the necessary illumination competing with stage lighting. When you consider that the projected area was approximately 60 feet high by 75 feet wide, the actual brightness drops dramatically. The projection servers were custom built by Förterer and his team. The rest of the components were “off the shelf” items found in many video systems, with the exception of machine vision near-infrared cameras and infrared emitters used for motion tracking. Preset values for the projection servers are controlled by two lighting desks (main and backup). The data to the projection servers is DMX protocol converted to Artnet via two converter boxes. However, since the projections are part of the lighting department, the operator also controls switched power throughout the show (for example, arc-source lighting, hazer power and opto-isolator power) in addition to the duties of video. Those who may not have had the opportunity to see this production may ask how this all comes together. It is easiest to break it down scene by scene to describe how the elements are used. At the beginning of the show, the Imperial Family comes under attack by a rival force firing arrows. During this scene, live arrows are launched by the performers along with additional arrows being fired by pneumatic cannons. To add to the drama, additional arrows are projected by a single projector, which eliminates the separation of the stacked image throughout the open space. The twins attempt to escape by sea, but are separated. The scene plays out with the performers acting out survival on the ocean in stormy weather. To complement this scene, storm clouds are projected onto a massive scrim. The projection system is connected via Ethernet to the audio effects console for this and other scenes in the show. During this particular scene, the audio effects operator triggers thunder sequences which concurrently trigger a lightning effect in one of three layers of projected clouds. Unlike with the arrows previously described which are created through particle generation, the clouds are randomly created through celular automaton algorithms. After many of the performers have been “tossed overboard,” the boat finally sinks by way of lowering the stage lift. To accentuate this, a video-projected “wave” ascends the scrim, ultimately overcoming the clouds. Should there be any delay in this transition, the projectionist has the ability to take control over certain aspects of the program (such as the speed of the ascension) to keep the transition as fluid as possible. The audience next finds themselves viewing an underwater rescue. The Nanny character descends behind the scrim on an acrobatic harness. The scrim is being lit by a water effect created by HMI, arc-source ellipsoidals with effects wheels. However, the performers are also being illuminated with infrared emitters, normally used for CCTV security systems. Their movement is tracked with the near-IR cameras, distributing their signal to video capture cards in the custom servers. The harshness created by the edge of the video black is mitigated by dousers placed in front of the projector lenses, softening the transition. Depending on the speed and amount of movement of the performers, projected bubbles are created around the performers. A trigger is sent to the Sound Effects console with intensity of the bubbles as well as positional data to audibly track the movement. The survivors eventually end up on a deserted beach. The beach is actually the SCD covered in one ton of granulated cork. To transition out of this scene, the automation operators tilt the deck to 90 degrees, allowing all of the cork to drop into a collection system in the basement. During this transition, the projected image of a cave wall appears on the now vertical deck. As previously stated, the scope of the projected image is much greater than the surface of the SCD. The projection system takes data from the automation system, then including the exact lift, tilt, and slew (rotation) of the deck at any given moment. The data is taken down to the 10,000th of a degree to ensure the highest precision of the image. With all of that data, the server maps the image live. Since the projection surface moves and can change instantaneously, there is no way to pre-record the effect. The image projected for the Shadow Play, Climb, and Blizzard (the next scenes of the show) takes the information of the automation, along with that received from the capacitive tile system, to create scenes from various rock textures to an ice wall. Sound effects are triggered by mechanical pegs that shoot out from the deck (the illusion of arrows being fired into the surface) and “rocks” that fall as the performers climb the ice wall. The three projectors originally received the same image at all times during the show. It was up to the projectionist to keep them aligned as much as possible to have the least amount of separation in three dimensional space. To best accomplish this, there were two separate alignment files saved in the projectors to align the stack onto the two main projection surfaces (scrim and SCD). However, with the newly upgraded system, each projector gets its own uniquely mapped image, allowing the image to stay aligned, no matter how the projection surface changes. This requires processing power for the 3D modeling that was unavailable during the creation of the show. In addition, the new projectors are brighter with more pixels and a greater contrast ratio. This allows for an even more detailed image over a larger area (now 60 feet high by 80 feet wide). During the scenes where the SCD is used with projection, the main source of light for the performers comes from the projectors themselves. By using three projectors, we reduce the chance that a single projector failure will be an issue. The projectors are powered by an uninterruptable source. Since the projectors themselves are only one component, the rest of the system also runs with live tracking backups. For instance, there are two projection computers running in tandem throughout the show (main and backup) and can be switched by the operator or automatically should one program fail. The Twin Sister ends up in a forest of giant snakes, bugs, and the Forest People. The projection helps to enliven the set of “trees” by adding vines. These vines react to the performance in two ways. First, the IR cameras track movement throughout the space and gather the vines to points where the movement surpasses a set threshold. Secondly, the operator can select an object (generally the character Firefly Boy) using the computer mouse and gather the vines to that point. This allows the projectionist to selectively track an object without relying on the camera to sense movement. The finale of the show is a battle between the Imperial Twins, helped by the Forest People, against the Archers. The SCD rises into a vertical position, giving the audience a birds-eye view of the battle. Each performer has an independently remote-controlled winch, allowing them to control their vertical movement. As they traverse the surface of the deck, they create an image akin to water ripples. Ninety capacitive tiles cover the surface of the deck with up to 64 sensing positions per tile. Every point can simultaneously report the amount of capacitive data at 60Hz. The data is sent from the SCD to the basement via wireless bridge, using broadcast frequency to avoid collision from other wireless traffic. That data is then sent over fiber optic transmission to the control booth via Ethernet protocol. The end result, according to Förterer, is an expression of “poetry, emotion, and content in the language of mathematics and algorithms.” The next time you visit Las Vegas, come see for yourself how art and technology combine for the ultimate live production: KÀ by Cirque du Soleil. For additional information on the show and for tickets,visit KÀ | Las Vegas show at MGM.