The San Francisco Art Institute is for the first time exhibiting a group of photographs and screen prints by Andy Warhol that it acquired through bequests from the Andy Warhol Foundation for Visual Arts.

An avid photographer and Polaroid fanatic throughout his career, Warhol left behind a trove of candid and posed pictures, many of which ended up in the hands of the foundation after his 1987 death. There were so many photos, in fact, that in 2007 — on the 20th anniversary of his death — the foundation made gifts of randomly selected Polaroids and gelatin silver prints to 180 different academic institutions. The SFAI ended up with 100 Polaroids and 50 black and white photos, as SFGate explains, and now it's exhibiting a selection of them at its Fort Mason campus.

The show is titled "From the Tower: Andy Warhol," and it's free to the public at SFAI's gallery at 2 Marina Boulevard, Fort Mason. The hours are Wed-Sun, 11 a.m. to 7 p.m. The showing is partly out of obligation — with the gifts came a stipulation that the work had to be shown, and the school has only exhibited the Polaroids once before, appropriately for only 15 minutes, in 2009.

Among the pictures in the exhibit are photographs of celebrities like Debbie Harry and Sylvester Stallone, a series of John Lennon with his son Sean at the beach, and portraits of sports stars like Chris Evert and Wayne Gretsky.

Also being exhibited for the first time ever are seven Warhol screen prints that the foundation donated in 2013. These include several of film star Ingrid Bergman.

As the Chronicle notes, this mini-exhibition is on until March 24, and it precedes a major one that's happening at SFMOMA in late May. That show, "Andy Warhol: From A to B and Back Again," spans three floors of the museum and is the first major Warhol retrospective since 1989. Says the museum, the exhibit "reconsiders the work of one of the most inventive, influential, and important American artists. Beneath the glamour of Warhol’s wide-ranging creations is a deep engagement with the social issues of his time that continue to resonate today."