The identical Oakes twins,Trevor and Ryan, who were profiled in the Reader in October in The Magic Easel, return to Chicago this week to begin a residency at the Field Museum. They’ll be using their remarkable method of splitting what the eyes see to create a perspective drawing of the museum’s great hall. From Damien James’s Reader story:

Their tripod apparatus, which they call “the easel,” in a sense allowed Trevor to see through the paper he drew on to the object beyond it being drawn. Normally, our two eyes unite what each sees individually into one picture; but the easel is designed to separate what they see. In this case, Trevor’s left eye saw the paper, his right eye Cloud Gate and the plaza around it.

The brothers liken the effort required to the effort most of us must make to see the three-dimensional picture in a Magic Eye puzzle. . . . “It is the same action by the eyes of separating one’s sight lines at that paper plane (such that they would be converging at a point behind the paper).”

The effect of this technique at Cloud Gate was that the two images seemed to overlap, as if the paper were transparent and the sculpture could be seen behind it. But this overlap occurred in a narrow band—roughly the distance between Trevor’s eyes—which was why he was drawing in two-inch vertical strips. When the paper was whole, Trevor looked past the concave grid that held it, but as it was sliced and narrowed, his right eye looked through the grid. The easel is the product of months of rigorous calculation and physical labor—its bars are precisely designed to all but disappear as Trevor looks beyond them.