I actually bought two tickets to the tour that included the “portal” illusion, just to figure it out. Like all magic, it is disappointing once you see the gag.
The person “transported” is a plant. Despite the magician’s excuse for not picking a random person in the audience, it was the exact same guy. The initials transported to the remote island and later revealed are a mere video trick. If you do the math, it would take less than a day or so to shoot all the possible initials on the person’s arm and call up the appropriate video from a hard disk on demand. In one of the performances I attended, Copperfield didn’t like the way the person had written the letters (with some flourishes) and made them redo them to look more “normal” so “everyone could see them clearly” (in other words, closely match the prerecorded video).
In the same show, they did the license plate illusion. I handled the plate. The guy bought a
license plate machine and some quick drying paint.
Unless you are a fanatical magic geek like me, take my word for it, just enjoy the sense of wonder and forget about the technique.
In one continuous shot, David and the audience member (who is in on it), pre-recorded a beach scene in Hawaii. Much of what you see is David and the guy on that day. When you can see their feet, or they are in the water etc., it’s them on that day. At one particular moment, the camera pulls back to a blank landscape which is mostly empty sky. For now, David is not there, but will be later.
During the show, the pre-recorded footage is being projected onto a bright, high-quality screen backstage. In front of this large screen, there is a camera set up that is broadcasting a live feed of this video to the audience. On the huge screen on-stage, the audience is seeing a live feed of a pre-recorded image that is projected onto a screen. With this set-up, David can stand in-front of the screen with his polaroid and arm and the audience will see him in front of sky and landscape.
It would work like this:
Video- David is seen walking on the beach (it’s the real footage). THe camera swings over to the guy playing in the water. When the camera swings back to blank sky, The real-life David is now standing in front of the screen that is being fed to the audience. He shows the polaroid, camera swings away and pans back to the pre-recorded David walking up the beach. All in one continuous shot, no green screen, no digital editing. simple. After reading this, watch it again and it’s very obvious.