Beckie Kravetz, assistant wigmaster of the Los Angeles Opera, primped the mountain of blond yak hair atop the singer’s head.      “I’m wearing yak hair?” asked Dale Wendel-Franzen,who plays Papageno in the production of Mozart’s “The Magic Flute” that opened last night at the Music Center/ “I’m not so sure I like that idea.”      For Kravetz, 33, a Venice resident who has been with the company since the fall of 1987, explaining the tricks of her trade to opera performers is part of the job of turning ordinary people into dreamlike visions of fantasy.      “It’s been sterilized,” said Kravetz, reassuringly. “Yak hair is coarser, and it holds a lot better than human hair. We like using it because it won’t fall down halfway through a performance.”      Kravetz, along with Wigmaster Rick Geyer, are responsible for the wigs, makeup and masks for the opera company, which for this show has 18 principal performers, 35 chorus members and 19 non-singing cast members. Formerly a Drama Student      The New York native who grew up in Arizona says she has come a long way from studying dramaturgy—the history of theater—and taking acting lessons at Yale.      “I did that for about a year and wasn’t really happy,” she said during an interview last week. “I kept volunteering to paint sets and make props when I should have been reading and writing. I wound up staying an extra year to do an internship in prop making.”      It was during that internship that Kravetz took a class in mask making.      “I had always loved the theater, and pursuing makeup and mask making seemed like a natural for me,” she said. “I just never knew you could have a profession doing it.”      After a brief stint making masks with puppet masters in New York, Kravetz moved to New Mexico and realized “the West is where I belong.” She was doing masks for the Santa Fe Opera when she met a wig and makeup specialist who had just signed a contract to open a new opera house in Houston. The woman needed an extra assistant.      A job opening with the Los Angeles Opera brought her to the West Coast during the fledgling company’s second season.      When she first arrived in Los Angeles, she worked on the chorus and crew members. Now she works on the cast’s lead members like Wendel-Franzen and Placido Domingo.      “Beckie knows my head really well,” Wendel-Franzen said, as Kravetz touched up the complicated mesh makeup used to give the performer a cartoonish look—making skin not look like skin. “I can’t complete my character, especially in a show like this with so much body language until I see the costume, the makeup and the wig.”      Much of Kravetz’s work has been on the job training.      “It’s the kind of business where you’re always learning, like an apprentice,” she said.      “Sometimes, you have to suffer through the mistakes to further the craft. But one of the things I like most about it is the legacy. There are some aspects of wigmaking that haven’t changed in 300 years.”      Wigmakers form their creations on wooden blocks stowed in a cluttered makeup and wig room at the Dorothy Chandler Pavilion.      For the principal performers, whose wigs must fit perfectly, canvas blocks are used. A plastic cap of the performers head is made, complete with hairline, and wigs are created on the form.      “Sometimes we’ll have a dark-haired lead who has to wear a blond wig,” Kravetz said while giving a tour backstage. “The wigs have to fit perfectly. Most of them are made from human hair, but we do use some synthetics and yak hair when we need a stiffer look.      “One of the roughest jobs we have is changing the age of people. Performers are cast for their voices and not for the way they look. Often I’m given someone who is very young but is going to play someone very old. Not only do we have to get the look right, but the makeup has to withstand the hours on stage.” Excitement Alive      Unlike film, opera offers the excitement of being in like theater, something that Kravetz loves.      “There’s a popular misconception that we’re hairdressers,” she said. “My art goes for exaggeration. I’m working in a 8,000 seat house, and you’ve got to ‘read’ to the back wall.”      Until she started working in the field, Kravetz didn’t like opera. “I was not a fan,” she said. “Now, I love it. I love the music and scale of the experience It’s a heightened reality. There’s a lot of opportunity for me to be an artist. I’m given faces as a canvas to create characters.”      Kravetz works about 9 1/2 months out of the year for the opera. She also does work on commercials and has taught art to mentally retarded and developmentally disabled adults at the Exceptional Children’s Foundation.      But there’s one time of year Kravetz work: Halloween.      “I totally ignore Halloween,” she said. “I live this stuff all year round.”