In 1945, near the end of “The Great Patriotic War” — the USSR’s costly repelling of the Third Reich — the Soviet Union designated Leningrad (now St. Petersburg) Russia’s first “Hero City.” Though running a close second to the Siege of Stalingrad in death toll, Leningrad’s ordeal was more than twice as long. The home of the Winter Palace (later the Hermitage Museum) and a repository of a fortune in pre-revolutionary art and literature, Leningrad was considered Soviet Russia’s head, not its heart. Nevertheless the city endured nearly three years of the German Army’s efforts to bomb and starve it.

Contrasting Tsarist splendor with Stalin-era endurance, the Siege of Leningrad has awakened the imagination of numerous filmmakers over the years. “Blokade,” a 1974 Soviet “super production” dramatizing the siege, was successful enough to spawn a sequel. Andrei Tarkovsky deals with the siege more tangentially in his autobiographical 1975 film, “The Mirror.” Sergio Leone died on the eve of commencing his own epic re-creation of Leningrad’s 900-day ordeal in 1989. Curiously, Aleksandr Sokurov makes no mention of it at all in his celebrated Hermitage-set history recap, “Russian Ark.”

No matter. The definitive film on the Siege of Leningrad has arrived. But it is neither a war epic nor an impressionistic personal reminiscence. “Blockade,” opening today on Film Forum’s main screen, is an hour-long compilation of found footage photographed during the siege. This new film’s black-and-white images are unadorned by narration, music, or explanatory intertitles. Contemporary filmmaker Sergei Loznitsa has only added background sound effects synchronized with footfalls and cannon blasts shown on-screen.

The effect is somewhere between watching an 1890’s vintage single shot proto-documentary Lumiere Bros. cinematograph and surveillance camera footage. In the early days of the siege, Russian soldiers walk enormous barrage balloons down bus lanes through busy traffic. A small cadre of captured Wehrmacht troops is led through the streets and you are there. Fall breaks, and the snows come. A pedestrian slips a little while scurrying across the street just ahead of a Russian tank. Bundled citizens transport their food rations on small sleds.

The siege wears on, one winter stretches out into multiple winters, and the same sleds are used to transport the dead. As thousands succumb to disease and starvation, winter’s dubious saving grace is that the corpses remain frozen. One montage of shots plays like a ghoulish “Candid Camera” where the gag is to see how long it takes before any passerby pauses over a shrouded body in the foreground.

Though there are a few staged moments in “Blockade,” for the most part the documentary cameramen keep a discreet physical distance from the growing misery they capture. The film’s minimal editorial manipulations and unfiltered presentation of survival helps “Blockade” to invest new meaning in the phrase, “raw footage.” In the late 1920s, filmmakers Walter Ruttman and Alberto Cavalcanti each made “city symphony” documentary abstractions that orchestrated everyday images of city life (Berlin and Paris, respectively) into intricate and dazzling montages. Using “Blockade”‘s lingering traveling shots of bereft survivors dragging their dead loved-ones to mass graves organized by the size of the corpse, Mr. Loznitza’s has created the cinema’s first “city dirge.”

“Blockade” is co-billed with “Amateur Photographer,” a disturbingly matter-of-fact travelogue created from photo albums and diaries belonging to a Nazi soldier charged with “administrative, economic, and retaliatory measures in captured areas” along the German-Soviet Eastern Front. Read as first-person narration and translated a beat later into accented English, the soldier’s gruesome play-by-play comes across like a language record for racist murderers. Atrocities are so effortlessly interpolated with banalities that one almost forgets to wonder how it is we’re hearing this horrible thug’s unapologetic genocidal war stories.

“Blockade” and “Amateur Photographer” are built on foundations of vintage black and white analog imagery. Unfortunately both films are projected from videotape, not from film. “Amateur Photographer” is particularly ill served by a slightly soft-focus color video sheen that dulls the sharp contrasty imagery in the snapshots of which it is almost entirely composed. Despite less than ideal digital makeovers, these films remain unvarnished and sobering looks at the extremes of wartime.

Until March 27 (209 W. Houston St., between Sixth Avenue and Varick Street, 212-727-8110).