Hollyguard : Landmark: A security system with infrared cameras and radar-activated lenses is installed to protect Hollywood sign.

The Hollywood sign has taken a cue from the Hollywood studios: It’s putting people in pictures.

A new security system using infrared cameras and radar-activated zoom lenses has been installed to keep vandals, tourists and college pranksters from trespassing at the famed hillside landmark.

Seventeen intruders were caught last week when sophisticated surveillance equipment hidden around the landmark sign was switched on for the first time, officials said Tuesday.

Motion sensors scan trails leading to the sign and activate video cameras that can see both night and day. Intruders’ pictures are recorded on a computer disk as evidence and city park rangers are alerted. Then loud speakers warn trespassers that they are being watched and that authorities are on their way.

“We’re ironing the wrinkles out this week,” said Los Angeles Chief Ranger Hector Hernandez, shouting to be heard over a speaker that was blaring the “you are being monitored . . . a park ranger is en route” message over and over in English and Spanish. None of the first 17 trespassers caught by the motion detectors will face prosecution. Ten of them fled when the loudspeakers announced they were being watched; the others were counseled by rangers and released, Hernandez said.

The vandalism crackdown comes as officials prepare to repaint the landmark for the first time in more than 15 years. And for the first time in its 60-year existence, it is being insured against earthquake damage and destruction from disasters such as an airplane crash.

Officials are hopeful the $90,000 surveillance system will finally solve the trespassing problem that has plagued the sign since it was erected in 1923 to advertise the Hollywoodland subdivision being built in nearby Beachwood Canyon.

The 450-foot-long sign--which can be seen throughout most of Hollywood but cannot be reached by car--has always been a magnet for the adventurous and the curious. Countless people have been injured trying to climb it. Several have died in falls--including actress Peg Entwhistle, who committed suicide by jumping from the H in 1932.

In the 1970s and ‘80s pranksters began altering letters to make it read “Hollyweed” (in recognition of a new state marijuana law), “Caltech” (on Hollywood’s 100th birthday) and “Go Navy” (before a football game at the Rose Bowl).

More recently the sign has been attacked by graffiti vandals. Although most scrawls cannot be seen from neighborhood streets a half-mile south of the sign, city workers have struggled to cover the damage.

A paint company has agreed to provide enough free white enamel to repaint the sign this fall. The job will take about 200 gallons and should last 20 years, according to Frank Daniels, a Sherwin-Williams Co. executive from Cleveland, Ohio, who inspected the sign this week.

In exchange, Daniels’ company will be allowed to advertise for a year that it painted the Hollywood sign, according to officials of the Hollywood Sign Trust, a nonprofit group that manages royalties from use of the landmark in films and commercials.

The trust has allocated about $40,000 to hire painters, said Chris Baumgart, trust chairman.

It is also spending $5,500 on an annual insurance policy for the sign. Baumgart said his group realized after the January earthquake that neither the city nor the Hollywood Chamber of Commerce probably could afford the estimated $400,000 that it would take to rebuild the landmark if it were destroyed.

The sign trust--which also paid for the surveillance system--has asked the Los Angeles City Council to increase the fine for those caught trespassing, Baumgart said. Intruders now face a $103 citation for illegally entering a “mountain fire zone.”

The new equipment includes microwave-type intruder sensors that can differentiate between humans and coyotes up to 1,500 feet away. The television gear consists of four daylight video cameras and four nighttime cameras equipped with laser-like infrared light sources.

Pictures viewed on TV screens at the Griffith Park ranger headquarters a few miles away are recorded on a computer hard drive. They can be transferred to videotape for use in court, Hernandez said.

Prosecutors from the city attorney’s office will be shown the new equipment once all the kinks are worked out, officials said. The tapes will allow the city to prosecute graffiti vandals; in the past, few have been caught in the act of spray-painting--a requirement for charges to be filed.

But nearly half of all Hollywood sign trespassers are tourists, Hernandez said.

“They’re honest, law-abiding citizens who don’t realize what they’re doing is illegal” and potentially dangerous to nearby residents of the brush-fire and erosion-prone canyon, he said.

“From down below they see what looks like a trail leading up from Beachwood Canyon to the letter O. It’s almost an advertisement to come on up.”

Park workers hope to transplant native chaparral to cover the pathway, Hernandez said.