escher quattro 1

	Escher Illusion - Illusion à la Escher - Illusione a la Escher
	This "four" is clearly an impossible perspective. The vertical branch V cannot start under the top of the L shape part and then end up on top of it. The challenge was to create a 3 dimensions structure which would give the same illusion effect when observed from a specific viewing position. Click on the design at left to see the result of my efforts. And see below how it was done.	V L

	First I cut the L shape part on a 2cm thick wood panel. The cut was made at a 45° angle so as to give the perspective shon in the sketch above right. Then I decided that, in order to be able to adjust their positions depending on the viewer position, the longer vertical shape V and the shorter one which shall go under the L shape, should be mounted onarticulated supports capable of moving up, down, left, right, front and back. The various views shown here should explain this point.

	The result is only visible, as shown on the image at right, from a specific viewpoint. Click on it to enlarge it.