ROBERT OLSEN was a great painter—and one of the most dedicated and humble artists I have worked with. Over the course of a decade, from 2000 to 2010, my gallery presented ten solo exhibitions of his work and featured his paintings, drawings, notebook pages, and videos.

Robert was a nighttime painter. He was out in the street of Los Angeles night after night, taking photographs to use as source material for his paintings. He preferred the very early morning hours, when the streets are empty and the city sleeps. Like no other painter, he was able to capture the quiet beauty of urban desolation and the profound sense of loneliness that life in Los Angeles triggers. His paintings, often small in scale, pinpoint that exact moment where the noise of the everyday quiets down into silence, where people confront their fundamental questions: Why am I here? Where am I going? And while many artists have examined the dark side of this vast city, no one has captured the urban anxiety brought on by the relentless pursuit of the American dream quite like Robert.

Robert was kindhearted and deeply supportive of his fellow artists. Even though he was a very active member of a community of artists, many of whom he knew from his time at UCLA, he had a singular determination that kept him apart from the crowd. Working with him was a profound pleasure. He was utterly professional, deeply dedicated to his work, and one of the hardest-working artists I have known.

I miss him greatly and mourn that Los Angeles has lost a great painter before his time.

Susanne Vielmetter is the director of Susanne Vielmetter Gallery in Los Angeles.