Technology has evolved so much in the 25 years that Jay Schwartz has been hosting Secret Cinema screenings in Philadelphia that recounting his history requires a bit of explanation.

Now that almost every multiplex exclusively screens movies digitally, even regular filmgoers may be unfamiliar with the tactile pleasures of an actual film projector of the sort that Schwartz lugs to every Secret Cinema event. When  Schwartz began collecting film prints, almost two decades before his first public screening, there was no such thing as home video, let alone HDTV or instant streaming access to almost any title imaginable.

A key moment, in fact, was when Schwartz was a student at Temple, paging through the classified ads that then took up sizable real estate in the very paper you now hold in your hands (presuming  you're actually holding a physical newspaper, not a safe assumption in 2017).

Jessica griffin / Staff Photographer
Jay Schwartz in his Port Richmond studio.

"I was glancing randomly at classified ads in the Philadelphia Inquirer," he says, "and there was an ad for someone selling a used 16mm sound projector for a hundred dollars. I thought it would be important for my class work, plus it seemed like a really fun toy."

Thus, Schwartz's library grew beyond the handful of 8mm films that he had been screening for friends on his parents' old home movie projector, and the seeds were planted for a collection that now numbers in the thousands of reels and that has long since moved out of his closet and into a climate-controlled workshop/warehouse.

The projector seller threw in a stack of old educational films, including one that still shows up on the occasional Secret Cinema program: a 1950s promotional short on how to choose the correct size bra and girdle.

That kind of campy, oddball ephemera has become central to Secret Cinema, though when Schwartz first carried his almost antique (even then) 16mm projector up the stairs of the Khyber in 1992, the focus was on little-known feature films. (That first night, it was the obscure 1956 rock musical Don't Knock the Rock, featuring performances by Bill Haley and His Comets and Little Richard.)

“You can see all kinds of stuff on YouTube,” Schwartz says, "but I enjoy showing people things they probably wouldn't see without me."

To celebrate his silver anniversary, Schwartz will spend the remainder of the year reviving some of the more popular programs, along with a few gems that he feels were overlooked during their initial screenings. The series will kick off Friday (25 years and one day from that initial Khyber screening) at the Maas Building with "The Best of Secret Cinema Short Films: The Early Years," an eclectic collection of audience favorites from the series' first five years -- some of which haven't been seen since 1992.

The evening will include offbeat rarities like the 1940s etiquette how-to "Let's Have a Tea," a 1932 documentary about Florida's sponge-diving industry, a collection of vintage Latin music shorts meant to be played on a long-obsolete film jukebox, and a 1960s educational guide to sharing, "Yours, Mine, Ours," among others.

Future programs will include the ever-popular “Uncensored Cartoons,” featuring politically incorrect animations by giants like Tex Avery and George Pal,  later this month at Fleisher Art Memorial; a “Trailer Trash” collection of cult film trailers in April at the Bryn Mawr Film Institute; and a return to one of Secret Cinema’s most atmospheric sites, Eastern State Penitentiary, in the fall. It was there, in the center of the long-abandoned prison, that Schwartz hosted one of his most memorable screenings: As a rainstorm outside began pouring through the dilapidated ceiling of the historic prison, the audience stayed put in their folding chairs, opening umbrellas to continue watching the evening’s prison-set feature.

To a hardcore film fanatic like  Schwartz, those are his kind of people, which is another reason he has kept up Secret Cinema for 25 years. "I like to show things that might be hard to see otherwise and that I think will interest an audience," he says, "but at core, my programming philosophy is 'What do I like?' So, at this point, my audience has probably evolved into a bunch of people that think like me."

"The Best of Secret Cinema Short Films: The Early Years," 8 p.m. Friday, The Maas Building, 1325 N. Randolph St. Tickets: $9, 267-239-2851,