Eliasson's pieces try to make the viewer participate and be aware of their physical environments. He also explores the often unnoticed relationship between the viewer and the object and how they can be interchanged. Moma curators describe his works as "ongoing exploration of subjectivity, reflection, and the fluid boundary between nature and culture."1
Round Rainbow from 2005, exemplifies Eliasson's portfolio very well. His focus for this piece centers around the element of rainbow formations that form in nature. The piece called for a tripod, a acrylic glass ring, HMI spotlight, and a motor. It appears to be set in a dark space, where the shadows and visual light patterns are the only focus. This installation piece looks very simple, construction and concept wise, but it has a very poetic and calming effect on viewers. The natural phenomenon behind the concept developed by the matierals and the environmental aspect of the piece seem to go very well with each other. The piece is currently located at the Hirshhorn Museum in Washington, DC.
The following link is an interesting podcast from a couple of visitors that saw the piece and give great detail, explanation, and critique of the artwork. Take a listen... http://www.podcast-directory.co.uk/episodes/%E2%80%9Cround-rainbow%E2%80%9D-by-olafur-eliasson-14473019.html