LASER SHOW : OBSERVATORY DISPLAYS ‘MOONROCK’

“Moonrock,” an upbeat multimedia laser show that premiered at the Griffith Observatory on Saturday, showcases the latest techniques for combining computer graphics with laser light, while also revealing the limitations of such entertainments.

The Laserium shows began at the observatory in 1973 with programs consisting of loops of colored light revolving in time to rock songs. The technology has grown considerably more sophisticated in the last 14 years: For “Moonrock,” the artists draw recognizable figures in lines of glowing color by reflecting laser beams off tiny, computer-controlled mirrors. These figures seem to move in three dimensions, gradually shrinking as they retreat into the starry dome of the planetarium.

The technique is most effective when used to create abstract figures, like the rectilinear pattern that continually redraws itself to the Rolling Stones’ “2000 Light Years From Home,” or the construction of turquoise loops that hop about to “Walking on the Moon” by the Police. The unique beauty of these non-objective shapes makes the attempts to produce recognizable images--like Neil Armstrong’s footprints--look awkward and silly.

The most striking visuals in “Moonrock” are a series of rapidly spinning patterns that juxtapose wedges and rings of brilliant color with bands of deep black. (The intensity of the pure laser light gives the contrasting darkness an almost tangible presence.) As these images retreat, they seem to draw the viewer into a lengthening tunnel--an uncanny illusion that induces a mild sense of vertigo.

The weakest aspect of “Moonrock” is the sound track, which mixes mid-’70s progressive rock (Led Zeppelin, Queen, Moody Blues) with old tapes of the astronauts and Presidents Kennedy and Nixon. The visuals warrant a more original accompaniment. And despite the technical advances, the laser artists still command a fairly limited vocabulary of effects: By the end of the one-hour show, the audience has become a little too familiar with them. (An additional caveat: The old-fashioned seats in the observatory will seem cramped to anyone over six feet tall.)

“Moonrock” represents both an advance and a promise. If laser imaging techniques continue to develop at their current rate, really dazzling entertainments should be possible within a few years. At present, the show is a pleasant, lightweight diversion for a summer evening, and the sweeping view of the brightly lit Los Angeles basin from the observatory provides an effective finale to the space-age imagery of “Moonrock.”

“Moonrock” plays at the Griffith Observatory in Griffith Park, Tuesday through Sunday at 9:15 p.m. and 10:30 p.m. Information: (818) 997-3624.