Theater has a reputation for being among the most ephemeral of the arts: Once you’ve missed a live performance, it’s gone for good.But that’s not quite true — at least not at the New York Public Library for the Performing Arts. It’s well-known among legiters that if you need to catch up on a production you missed — stretching back to 1970, when the Theater on Film & Tape Archive was started — the Library for the Performing Arts (LPA) at Lincoln Center is the place to go. But it might not occur to most library users that the LPA’s initiatives for recording and archiving theater, dance and other performing arts push this library out of the realm of the Dewey Decimal System and into the production and preservation of film and video. “We’re not just a repository of people’s materials,” says LPA exec director Jacqueline Z. Davis. “We’re actively documenting theater and dance in this country.” Those efforts, including the production of videos of shows on Broadway, Off Broadway and playing regionally, require a budget that hovers around $915,000 per year, but can vary according to the vagaries of nonprofit funding. It’s a budget with limits, which means not all shows get the nod to be filmed by TOFT, as the Theater on Film & Tape archive is called. Just ask stage producers who’ve been disappointed when their productions were passed over. “We don’t have the money to get, for instance, everything on Broadway,” says TOFT director Patrick Hoffman. “We have to make some very tough curatorial choices as to what will be documented and what will not.” Among the curators who help make such decisions — not just for the filmed components of the LPA collections but also for the performance documents that include photos, press coverage and stage manager scripts — are Karen Nickeson, acting curator of LPA’s Billy Rose Theater Division, and curator Jan Schmidt of the Jerome Robbins Dance Division. “We’re interested in documenting individuals and artistic organizations that have really made an important contribution to the culture and history of the art,” Nickeson says. “It’s an evaluation process that looks at an individual’s output over the years and how important we think it is. It might be somebody who is considered somewhat obscure, but if they made a huge contribution in a certain genre, we would certainly want to have them in our collection.” The filming of a Broadway production generally costs around $15,000, according to Hoffman, with the number of cameras and their placement in the theater tailored to the specifics of the show. Vanessa Redgrave’s solo outing “The Year of Magical Thinking,” for instance, was filmed with a single camera; Disney tuner spectacle “The Lion King” was shot with five. Editing is done on the fly during the performance, sometimes with the input of the helmer of the show being recorded. (A show for the dance collection, on the other hand, is edited post-performance.) The number of productions documented varies per season. Last year, TOFT filmed about 60 shows total around the country, with the dance division shooting an additional 35. For some shows, depending on funding availability, TOFT also produces on-camera interviews with those involved in the production. Hoffman points out that producers can always opt to have a show filmed on their own dime, in which case TOFT is happy to add it to the archive. In addition, sometimes funders step forward to back the recording of specific productions — as was the case with the devoted Ralph Fiennes fan who supported the filming of the Fiennes-toplined Broadway revival of “Hamlet” in 1995. Because the TOFT archive’s most frequent users are industry types with a specific professional goal in mind when they take a look at a show, the recordings aim to capture more information than a casual viewer would require. “We’re trying to document not just individual performances but also the director’s work, the blocking, the choreography, the set design, how the set moved on and off the stage, the lighting design, the projection design, all of that,” Hoffman says. Such elements come in handy when, for instance, a show that originated Off Broadway makes the move to the Main Stem after a hiatus. Hoffman reports that a handful of people involved in the upcoming Broadway production of “The Scottsboro Boys,” for instance, came in to check out the taped version of the Off Broadway incarnation that played the Vineyard Theater in the spring. The LPA was founded in 1965 by the developers of Lincoln Center, of which the library serves as a constituent (although it is run by the New York Public Library system). The film and video archives were established soon there-after. With a theater collection that stretches back 40 years — and in the case of the dance division, even longer — the performance recordings include a number of different formats reflecting the march of technology from film to video to DVD. “We preserve materials when they come in, but in the course of 20 years, the way we preserved them becomes obsolete, and then it all has to be re-preserved,” says dance division curator Schmidt. “We’re constantly working to get funding to preserve and, eventually, move everything into a digital form.” Part of the process includes the imminent establishment of a “trusted repository” for digital materials, which can maintain high standards of authentication, verification, and format migration. Execs in the library hope eventually to increase general online access to parts of the LPA’s film and video collections. Barred from such online availability, however, would be the TOFT collection of performance titles. Due to legit union protections for their members and their work, the TOFT archive is restricted to a vetted crowd that includes industry types as well as scholars, students and journos. That means no strolling in off the street just because you feel like watching a show. “If it’s just that your grandmother never bought a ticket to see Nathan Lane in ‘Guys and Dolls,’ that’s not a legitimate reason to look at the collection,” Hoffman says.