In the 1930s, Grierson further argued in his essay First Principles of Documentary that Moana had "documentary value." Grierson's principles of documentary were that cinema's potential for observing life could be exploited in a new art form; that the "original" actor and "original" scene are better guides than their fiction counterparts to interpreting the modern world; and that materials "thus taken from the raw" can be more real than the acted article. In this regard, Grierson's views align with Vertov's contempt for dramatic fiction as "bourgeois excess," though with considerably more subtlety. Grierson's definition of documentary as "creative treatment of actuality" has gained some acceptance, though it presents philosophical questions about documentaries containing stagings and reenactments.
In his essays, Dziga Vertov argued for presenting "life as it is" (that is, life filmed surreptitiously) and "life caught unawares" (life provoked or surprised by the camera).
Documentary Practice is the complex process of creating documentary projects. It refers to what people do with media devices, content, form, and production strategies in order to address the creative, ethical, and conceptual problems and choices that arise as they make documentaries.
Early color motion picture processes such as Kinemacolor and Prizmacolor used travelogues to promote the new color process. (In contrast, Technicolor concentrated primarily on getting their process adopted by Hollywood studios for fictional feature films.)
Also during this period Frank Hurley's documentary film, South (1919), about the Imperial Trans-Antarctic Expedition, was released. It documented the failed Antarctic expedition led by Ernest Shackleton in 1914.
With Robert J. Flaherty's Nanook of the North in 1922, documentary film embraced romanticism; Flaherty went on to film a number of heavily staged romantic films, usually showing how his subjects would have lived 100 years earlier and not how they lived right then. For instance, in Nanook of the North Flaherty did not allow his subjects to shoot a walrus with a nearby shotgun, but had them use a harpoon instead. Some of Flaherty's staging, such as building a roofless igloo for interior shots, was done to accommodate the filming technology of the time.
Pare Lorentz's The Plow That Broke the Plains and The River are notable New Deal productions, each presenting complex combinations of social and ecological awareness, government propaganda, and leftist viewpoints. Frank Capra's Why We Fight series was a newsreel series in the United States, commissioned by the government to convince the U.S. public that it was time to go to war.
In Canada the Film Board, set up by Grierson, was created for the same propaganda reasons. It also created newsreels that were seen by their national governments as legitimate counter-propaganda to the psychological warfare of Nazi Germany (orchestrated by Joseph Goebbels).
In Britain, a number of different filmmakers came together under John Grierson. They became known as the Documentary Film Movement. John Grierson, Alberto Cavalcanti, Harry Watt, Basil Wright, and Humphrey Jennings amongst others succeeded in blending propaganda, information, and education with a more poetic aesthetic approach to documentary. Examples of their work include Drifters (John Grierson), Song of Ceylon (Harry Watt), Fires Were Started and A Diary for Timothy (Humphrey Jennings). Their work involved poets such as W. H. Auden, composers such as Benjamin Britten, and writers such as J. B. Priestley. Among the most well known films of the movement are Night Mail and Coal Face.
Cinéma vérité and similar documentary traditions can thus be seen, in a broader perspective, as a reaction against studio-based film production constraints. Shooting on location, with smaller crews, would also happen in the French New Wave, the filmmakers taking advantage of advances in technology allowing smaller, handheld cameras and synchronized sound to film events on location as they unfolded.
Although the terms are sometimes used interchangeably, there are important differences between cinéma vérité (Jean Rouch) and the North American "Direct Cinema" (or more accurately " Cinéma direct", pioneered among others by French Canadian Michel Brault, Pierre Perrault, Americans Robert Drew, Richard Leacock, Frederick Wiseman and Albert and David Maysles).
The directors of the movement take different viewpoints on their degree of involvement. Kopple and Pennebaker, for instance, choose non-involvement (or at least no overt involvement), and Perrault, Rouch, Koenig, and Kroitor favor direct involvement or even provocation when they deem it necessary.
The films Primary and Crisis: Behind a Presidential Commitment (both produced by Robert Drew), Harlan County, USA (directed by Barbara Kopple), Dont Look Back (D. A. Pennebaker), Lonely Boy (Wolf Koenig and Roman Kroitor), Chronicle of a Summer (Jean Rouch) and Golden Gloves (Gilles Groulx) are all frequently deemed cinéma vérité films.
The fundamentals of the style include following a person during a crisis with a moving, often handheld, camera to capture more personal reactions. There are no sit-down interviews, and the shooting ratio (the amount of film shot to the finished product) is very high, often reaching 80 to one. From there, editors find and sculpt the work into a film. The editors of the movement — such as Werner Nold, Charlotte Zwerin, Muffie Myers, Susan Froemke, and Ellen Hovde — are often overlooked, but their input to the films was so vital that they were often given co-director credits.
Famous cinéma vérité/direct cinema films include Les Raquetteurs, Showman, Salesman, The Children Were Watching, Primary, Behind a Presidential Crisis, and Grey Gardens.
Box office analysts have noted that this film genre has become increasingly successful in theatrical release with films such as Super Size Me, March of the Penguins and An Inconvenient Truth among the most prominent examples. Compared to dramatic narrative films, documentaries typically have far lower budgets which makes them attractive to film companies because even a limited theatrical release can be highly profitable.
The nature of documentary films has changed in the past 20 years from the cinema verité tradition. Landmark films such as The Thin Blue Line by Errol Morris incorporated stylized re-enactments, and Michael Moore's Roger & Me placed far more interpretive control with the director. Indeed, the commercial success of these documentaries may derive from this narrative shift in the documentary form, leading some critics to question whether such films can truly be called documentaries; critics sometimes refer to these works as "mondo films" or "docu-ganda." However, directorial manipulation of documentary subjects has been noted since the work of Flaherty, and may be endemic to the form.
The recent success of the documentary genre, and the advent of DVDs, has made documentaries financially viable even without a cinema release. Yet funding for documentary film production remains elusive, and within the past decade the largest exhibition opportunities have emerged from within the broadcast market, making filmmakers beholden to the tastes and influences of the broadcasters who have become their largest funding source.
Modern documentaries have some overlap with television forms, with the development of "reality television" that occasionally verges on the documentary but more often veers to the fictional or staged. The making-of documentary shows how a movie or a computer game was produced. Usually made for promotional purposes, it is closer to an advertisement than a classic documentary.
Modern lightweight digital video cameras and computer-based editing have greatly aided documentary makers, as has the dramatic drop in equipment prices. The first film to take full advantage of this change was Martin Kunert and Eric Manes' Voices of Iraq, where 150 DV cameras were sent to Iraq during the war and passed out to Iraqis to record themselves.