The documentary Ringl and Pit, completed in 1995 by Juan Mandelbaum, has been quietly attracting attention and praise, largely through an international network of screenings in museums and festivals. Tonight it can be seen on WNET. There's no reason to be quiet anymore.This is the story of Grete Stern and Ellen Rosenberg Auerbach, who met in Berlin in the 1920's after leaving their Jewish middle-class homes. It was the time of the fragile Weimar Republic, which one of them recalls as ''a unique moment of experiment and change.'' Both women were interested in photography, then a male-dominated field. But as a historian notes, this was the first female generation in Germany that ''could move to the city, live on their own and not be considered prostitutes.'' Here was the emergence of the ''new woman,'' her most prominent emblem being Dietrich.So Stern and Auerbach could very well be hailed as feminist pioneers as, in 1929, they opened their own advertising photography studio, reaching back to their childhood nicknames to call it ''Ringl and Pit.'' With a laugh, they confide that Stern and Auerbach would have sounded like a Jewish clothing manufacturer. They quickly became known for their unconventional depictions of women. At an exhibition in Brussels, they won first prize for a hair lotion advertisement. They used models with their backs to the camera, highly unusual for that time. One ad featured a woman being laced into a bridal corset. ''Maybe I had a pornographic streak in me,'' Ms. Auerbach says impishly.The most refreshing aspect of this portrait is that while the two women are deeply serious about their endeavors, they refuse to take themselves too seriously. Of their work in Berlin, they say, ''It didn't occur to us that we wanted to be different.'' They dismiss psychoanalytic interpretations of their work as ''these inexplicable, learned things.'' They simply lived in a breakthrough era that had as its center the Bauhaus, with its functional melding of art, science and technology.But in 1933, Hitler and the Nazis took over, and Weimar was finished. Ms. Stern and Ms. Auerbach were among the fortunate who realized what was happening (''In a country with concentration camps, you cannot live,'' Ms. Auerbach says simply), and they quickly left Germany. Ms. Stern went to England, Ms. Auerbach to Palestine for a couple of years.They met again in England, but then were separated for 10 years by World War II. Ms. Stern settled in Argentina, Ms. Auerbach in New York. They never worked together again, but they remained lifelong friends.The extraordinary story of Ringl and Pit offers a splendid cast of characters, from Brecht to de Kooning. Very much products of their time, the two women are deliciously blunt, cutting to the point without diplomatic embellishment. Ms. Stern still lives in Buenos Aires (Mr. Mandelbaum, the producer, has roots in Argentina); Ms. Auerbach lives in Manhattan. In May, Ms. Stern will be 93, Ms. Auerbach 91. They are remarkable women, and this documentary, vividly capturing precious slivers of history, does them full justice.