By (author) Matthias Haldemann, Edited by Kunsthaus Zug
p.28 "Light is a sculptural material for Turrell and he it physically palpable, like sound. Precise, but inconspicuous structural devices are designed to create this impression. The circular opening of ""Skyspace Piz Uter" 2005 Zuoz, Germany
has a sharp bevelled edge that reinforces the impression of flatness. And, as far as Turrell is concerned, a round space is better suited to the realm of perception than a rectangular one anyway. Moreover, the intensity and brightness of the white in the upper part of the room not only make the sky seem flatter than it really is, but also make its colours deeper and darker, outside the intense, luminous ultramarine is but a pale grayish blue. The same is evidently not the same and we cannot trust our own eyes: they see more than is actually there."