The Ultimate Card Levitation is the next entry in our series of digital magic tricks. Following the success of our previous video; "Greatest Card Trick Ever" we wanted to go for a slightly grander effect. Having seen a variety of web videos of magicians levitating a single card using wire, we thought it would be fun to see something that couldn't be done by traditional methods. Eventually we decided that instead of levitating one card, our magician would float an entire deck of cards over the crowds in Times Square.
Much like our previous card trick, the majority of the people seen in this video were not planted in the audience. To achieve believable reactions to the CG trick, we shot for several days with a Canon 5D Mark II, recording real visitors gesturing at a giant interactive display. This enormous screen gathers people throughout the day to play a virtual dunk tank game, which requires people to fix their gaze upward and extend their arms outward in order to guide a virtual beach ball to a target. This allowed us to record a plate of real people who look surprised, entertained, and appear to be interacting with the floating cards that would later be added in.
The levitation trick was a far more ambitious project for us than our last video. Although character animation wasn't required, there was a significant amount of complex camera-tracking to be done. To maintain a candid, hand-held feel, the camera needed to be constantly moving and whipping around to different points of interest. This often left nothing more than a blurry streak for our tracking software to process. In the end, three separate software packages were required to get the job done. We used Autodesk Matchmover on the stable footage, PF Track for the more erratic and complex shots, and when all else failed, we used Mocha Pro's 3D planar tracker for the problematic, blurry and nearly hopeless camera moves. Sometimes we used two tracking programs in the same shot. The end result was a series of VFX shots that don't feel staged or professionally shot, but rather recorded at random by an onlooker with a cell phone.
Because the gestures of the crowds were very specific, we chose to hand-animate the cards. This method, though more labor intensive, allowed for an extra level of control over each individual card. Only on some shots were dynamics necessary to achieve believability in the motion of the cards, such as when they interact with surfaces or each other.
In the end, the Ultimate Card Levitation is a video trick designed to fool your eyes. It is meant to give the viewer a brief moment of surprise as you witness the impossible and experience an ephemeral belief in magic.