Fred Wiseman is the grand old man of documentary film making. Over the course of his long career, he has made 41 movies, the vast majority of them documentaries. They tend to share certain traits. They are often quite long. They rely entirely on dialogue: Wiseman never uses narration in his documentaries. And they often focus on institutions. Wiseman has done films about a mental hospital (“Titicut Follies”), a police precinct (“Law and Order”), and a high school (“High School”). Some of his films have the force of an exposé; others impart the documentary equivalent of a big wet kiss.

Wiseman’s latest film falls into the second category. Entitled “At Berkeley” — and running some four hours long — it attempts to do nothing less than capture the breadth of activities at the University of California, Berkeley, probably the finest public university in the country. When I asked Wiseman recently what he hoped viewers would get out of the film, he said, “I hope they come away with a feeling that it is a great university, run by people of intelligence and sensitivity, and working hard to maintain standards and integrity.” That comes through loud and clear. We watch a doctoral candidate who appears to have designed an apparatus allowing a paraplegic to walk. (At least that’s what it looks like; sometimes a little narration would help.) An English professor teaches Thoreau. A string quartet plays. A field hockey team scores a goal. Robert Reich, the former labor secretary, engagingly teaches a class. And so on.

In the forthcoming issue of the Carnegie Reporter, my friend Nicholas Lemann has a wonderful essay about the dual — and in some ways, conflicting — roles of the American university. One role is mass higher education, which is “mainly concerned with teaching.” The other role is high-end research, in which tenured faculty “pursue knowledge and understanding without the constraints of immediate practical applicability,” as Lemann puts it. “At Berkeley” has plenty of scenes of both — but never stops to contemplate whether this is still the best way to run a public university.

The reason that is a question worth asking is that the real story being told in “At Berkeley” is about money. From August to November 2010, when Wiseman was filming, the university was going through a brutal time. State funding had dropped from some 40 percent of its budget not all that many years earlier, to just to 16 percent in 2011. This school that had once been quite affordable for its students — like the rest of the California university system — now costs $33,000 a year for California residents, including room and board.

Thus there are scenes of meetings in which administrators talk about imposing centralized purchasing on the faculty. Students furious about increasing tuition and fee increases occupy a library. A faculty member tells her class how outraged she was that a $6,000 “discretionary fee” was being added to several graduate programs. In one scene, administrators talk about their new push to find students in Asia; what is not said is that at a school where 40 percent of students still pay very little — because they are poor and can get scholarships — the Asian students are likely to pay the sticker price.

Throughout the film, the university’s then-chancellor, Robert Birgeneau, laments the plight of the middle-class student — students whose parents make too much money to get them financial aid, but who fundamentally can’t afford to go there. Implicitly, Wiseman is asking whether, for all its dazzling breadth, Berkeley can still be that first step on the ladder of upward mobility for California’s middle class, which is what the university system was originally designed to do.

Berkeley, however, is the wrong place to find that answer. Just in the two years since Wiseman stopped filming, the school has raised $3 billion, while handling, last year, 67,650 applications, the most in its history. Its status as one of the country’s elite universities means that it is not forced to ask any financial question tougher than whether faculty members will go along with centralized purchasing. (It has also since begun a financial aid program for middle-class students.)It’s the other schools in the California system where the harder questions about the role of a public university need to be asked. Like Berkeley, they have seen their state funding slashed. But unlike Berkeley, it hasn’t been so easy for them to bounce back. Should they use more online courses? Change their mix of research and teaching? Aim for the same students as Berkeley, or focus on educating the middle class? The real issue is: how do you make college affordable again? Berkeley, being Berkeley, will do just fine. But unless everyone else in higher education takes a hard look at their model, the promise of higher education as the means to upward mobility will continue to diminish.