Early on Monday evening, Iris van Herpen could already feel the vibration in the room. The designer was standing in the glass lobby of the Brooklyn Museum , light streaming in, as her exhibition “ Iris van Herpen : Sculpting the Senses” welcomed its first visitors during the Brooklyn Artists Ball. “It’s been such a joy, because I’ve been working on the exhibition for such a long time,” said the designer of getting to experience the final installation. “It was just finished yesterday, and that was when all the light was done, and the sound was on — and then it just suddenly feels it’s all one whole,” she added. “It’s really a dream come true.” While the exhibition opens to the public later this week, the museum offered an early preview during its annual gala fundraiser, which honored the Dutch fashion designer. You May Also Like Van Herpen has been tweaking her retrospective exhibition as it travels to various museums.…