"Artscope," a nightly folk-fest for serious art enthusiasts, begins this Friday on the Mall behind the Air & Space Museum. It's a cross between a '60s happening and an art history survey course.

Billed as an after-dark cinema happening with 100 films nightly, it starts at 9:15, running for two hours an evening, through August 7. Cordless headsets that tune in soundhjtracks as viewers walk from screen to screen may be rented at the gate -- an option recommended for those wishing to avoid total confusion.

Unfortunately, sometimes dealing with the technology interferes with appreciating the art. At a preview, a group of Smithsonian Associates wandered among 16 screens set in a giant circle, waved magnetic-tape receivers as if pointing Geiger counters, adjusted headsets and carried optional plastic lawn seats. They took in as many of the films as patience and science would allow.

"You getting anything?" was the most- asked question. If they stood in the right place, they could hear the story of The Pieta, which screened next to a survey of Incan art, or pick up music and a brushstroke-by-brushstroke description of Turner landscapes. Looming behind the screens, the lighted Capitol Dome and Washington Monument provided the backdrops.

Dolby it ain't, and watching PBS documentaries is easier. People tripped over electrical cords and lit matches to read programs. Of course, the images always looked more interesting on the screen at the opposite side of the circle.

Art dealer and filmmaker Anthony Roland, who first offered the program at last year's Edinburgh International Film Festival, says Artscope represents "an effort not to impose the film medium on art." Indeed, the cinematic possibilities for adding life to the subject matter -- whether Greek pottery, Rembrandt or Picasso -- seem to have gone untapped.

But hardcore esthetes probably won't be bored even by the 1965 documentary from Czech television. Steve and Barbara Spangler of Arlington allowed that they probably could see similar films at free noon lectures at the National Gallery. But they raved about the High Renaissance film on Leonardo, Raphael, Michelangelo and Titian. Coralie Farlee of the District, who is studying watercolor art, said she expected more critiques in the show, rather than "primarily cultural narratives." But she got a kick out of the artsy picnic atmosphere. ARTSCOPE -- Opens Friday at 9:15, nightly through August 7 on the Mall between Fourth and Seventh Streets. (Raindates August 8-16.) Free. Optional headsets $4 at the gate or $5 in advance at Ticketplace.