We’ve all seen the cut-out of triangles and squares that, when rearranged, results in a new shape that has a larger or smaller square footage than the original. This is achieved through imperceptible differences in the sizes of the shapes (slightly different angles or thick versus skinny borders, etc) between the before and after shots.
But the video linked above is real time and I don’t see where the extra tile comes from (three times, no less!). Is there slight of hand involved? Is he palming the extra three tiles when he “puts them back” into the puzzle?
If I create a puzzle like that, will I easily be able to duplicate the result or is there some slight of hand involved?
Yes, it is not “sleight of hand” as he says in the explanatory video, it is (rather basic) camera trickery. Not all deceptive trickery is sleight of hand, which means actually doing something deceptive with your hands. It is stuff like palming objects or manipulating things with your hands in such a way that it is not visible, or not noticed. None of that is involved here, just camera trickery and some clever geometry.
I happened upon another video of the same trick - and this time without the cuts that the first one has. It’s clear that the guy flips over the large piece in the middle, he doesn’t truly switch it out with another differently sized piece as suggested. For this to work, it’s clear that the surface areas of the top and bottom must be different, which would require a slightly slanted edge on the near and far side of the large piece.
So yes it is sleight of hand, and even though it’s a pretty simple move, I’m not sure how easy it would be to pull off with people sitting in front of you watching your every move. Obviously the flipping over was so obvious in the first video, the guy felt he had to edit it out.