After recent exhibits of Gene Davis, Thomas Downing, and Sam Gilliam, the summer of “All Washington Color School, All the Time” comes to a close with its final local celebrity: Morris Louis. Educated at the Maryland Institute of Fine and Applied Arts, Louis lived in D.C. for his most prolific period, where he painted his multihued large canvases in the dining room of his home. The Hirshhorn categorizes the exhibit by the method Louis used to stain his unprimed canvases—“Veils” are translucent and overlapping, “Florals” stem outward from the center of the work, “Unfurleds” creep inward from the edges of the canvas, and “Stripes” are the most recognized mark of the Washington Color School. Louis’ major contribution to contemporary art was his decision to eliminate the brush when spreading his diluted paint, manipulating the canvas instead—a technique he adopted from Helen Frankenthaler. Exemplary of this method is Point of Tranquility, a piece in the permanent collection of the Hirshhorn, and a part of the “Florals” period. Every color in the spectrum emanates from a central point, with colors bleeding into one another and creating a halo of pigment around each petal; like many of the artist’s works, it satisfies Louis’ goal, which he once claimed was to “produce a delicious pain in the eye.” Diane Upright, the foremost authority on Louis, will give a free lecture on the exhibit at 7 p.m. Thursday, Sept. 20, in the Hirshhorn’s Ring Auditorium. The exhibition is on view from 10 a.m. to 5:30 p.m. daily, Sept. 20 to Jan. 6, 2008, at the Hirshhorn Museum and Sculpture Garden, Independence Avenue and Seventh Street S.W. Free. 202-633-4674. —Maura Judkis