That's not photoshop; that's an actual cloud hovering inside an actual room. Artist Berndnaut Smilde merges art and science to create small man-made clouds that exist — albeit for just a moment — indoors.
Smilde uses a fog machine to make the actual clouds, but also carefully regulates the humidity and temperature. Even so, these installations exists for a mere moment before dissipating inside the room. If you're not there in the moment, then you only get to experience these brief scientific sculptures as photographs.