THE motion-picture branch of anthropology, known as ethnographic film, is a field that never tires of asking big questions - about the world and also about itself.
True, some ethnographic filmmakers are content to make conventional documentaries that simply show new things, teach new facts, and, at best, guide moviegoers to a new awareness of human diversity and complexity.
But others regard their own profession as grist for critical examination. They wonder what gives scientists and documentarists the right to proclaim themselves ``experts'' on other cultures and ways of life. They worry about film's ability to turn living people and societies into fixed cinematic patterns that diminish their wholeness and variety. They ponder the responsibility they bear for lapsing into simplistic concepts and reinforcing unconscious stereotypes - which may then serve the designs of commercial or political interests with oppressive or exploitative goals.
The Margaret Mead Film and Video Festival, established in 1977 by the American Museum of Natural History, has become the most visible and valuable United States forum for addressing these issues. Named after a renowned anthropologist with a special interest in visual communication, it screens an annual program of films and videos representing a broad spectrum of cinematic theories, practices, and opinions.
This year's edition signals the continuing thoughtfulness of the festival by presenting a retrospective of Timothy Asch's major works. A central figure in ethnographic film since the 1960s, he has wrestled openly and intelligently with the challenges of his field.
Included in the series is Asch's best-known work, ``Ax Fight,'' made in 1971 and an excellent example of his innovative approach. Filmed in the Amazon Basin with his colleague Napoleon Chagnon, it centers on a violent conflict that erupted just as the filmmakers started their camera. Instead of merely recording the event, the movie deconstructs and reconstructs the images captured by the camera, acknowledging the filmmakers' uncertainty as to what really happened and showing how deceiving appearances and assumptions can often be. It is a classic documentary that opens up many of the provocative questions Asch has explored during his career.
Also featured in the festival is Jean Rouch, a towering French filmmaker who is equally reluctant to assume the role of ``objective expert'' when approaching a different society. Rouch's solution to this problem is to plunge himself as deeply as possible into the West African cultures he likes to film, inviting people from the region to join him in improvising stories that express their ways of life from their points of view.
His latest movie, ``Madame L'eau,'' visits an area of Niger where drought and changing riverbed patterns have brought hunger and distress to the community. Deciding that a windmill would solve their difficulties, they head for Holland to learn the skills and acquire the equipment they need.
Rouch's camera goes right along with them, and during their odyssey they act out subplots and stories that reflect the tensions, trials, and triumphs that arise from their encounter with European society. Some might fault ``Madame L'eau'' for showing African people as less than self-sufficient and needing European support to survive; but Rouch's obvious respect and goodwill toward his African friends, who have collaborated with him in other films over many years, lays such criticisms largely to rest.
Another probing work in the festival is ``The Anthropologist,'' by Andrea Gschwendtner, a German director. It is an ethnographic film about an ethnographic filmmaker: Rudolph Poch, an Austrian anthropologist who pioneered the use of cinematic and phonographic devices, doing field work in the Kalihari Desert and elsewhere before transferring his activities to Austro-Hungarian prison camps during the World War I era.
Gschwendtner's study shows how Poch's notion of ``objective research'' led him to treat his human subjects more like objects than people - and demonstrates how readily this ``scientific'' attitude was picked up and exploited by Nazi murderers with a ``master race'' ideology. This is a chilling and compelling film.
Other items on the Mead program include:
* ``Imagining Indians,'' by Victor Masayesva Jr., a Hopi filmmaker and video artist. This fascinating study looks at popular American movies such as ``Dances With Wolves'' and any number of John Wayne westerns, showing how they convey misrepresentations of native-American life and history. Lending more complexity and interest to the subject, Masayesva also indicates how Indians contribute to this process by participating, consulting, and otherwise legitimizing Hollywood's frequently dubious projects. The result is a stimulating, unsettling, and sometimes humorous look at an important topic.
* ``Zoo,'' by Frederick Wiseman, a leading documentarist. Here he visits the Miami Metrozoo, where - for his curious camera, at least - people are often more interesting to watch than the animals they've come to gawk at, care for, or study. Wiseman breaks no new cinematic or sociological ground, but his images are consistently vivid and revealing.
* ``Black Man's Houses,'' by Steve Thomas. During the 1830s, a reservation was established in Tasmania for aboriginal people whom European settlers wanted to place out of sight and mind. Today their lighter-skinned descendants have reoccupied the area, and Thomas's carefully made film explores the history of their racial oppression through their impressions, experiences, and memories.
* ``The Schvitz,'' by Jonathan Berman. ``The steambath,'' that is, where diehard heat-lovers sit in 240-degree F. temperatures and enjoy every minute of it. Berman's jokey film doesn't explain why this European-Jewish tradition has persisted so long in the US or why it's apparently fading out today, but it's entertaining while it lasts.