To art history buffs, clouds are effectively synonymous with Dutch art (particularly that Golden Age style of landscape painting in which dramatic, sweeping, cotton ball-like formations overwhelm the terrain). Contemporary artist Berndnaut Smilde brings this tradition into the twenty-first century—and indoors. His real-life cloud installations consist of precise mixtures of machine-generated light, humidity, temperature, and smoke. Hovering inside empty galleries, the clouds confine boundless atmosphere within solid walls. Usually, Smilde’s clouds are seen only in photographs: after regulating his interior space to ideal atmospheric conditions, Smilde shoots a burst of fog from a smoke-machine to create a hazy, floating mass that disappears almost as instantly as it materializes. His clouds are just as transient as the real thing, which is bad news for those who wish to see the works in person.

This video from Italian television shows the artist creating one of his clouds from start to finish: