Hollywood slang for B-Western — cheaply made, thin plot, horses as special effects. Exploitation fodder for quick returns, not art.
The term originates from the 1920s and describes those rapidly assembled Western films that studios used as exploitation machines—named after the oatmeal (oats) that horses ate, which stood metaphorically for cheap, fast production. On set, you immediately notice what you're working for: minimal shooting time, reduced budget, local extras instead of established character actors, landscapes that had to function, not impress. The story was secondary—chases, simple good-vs.-evil constellations, repetitive action patterns. Cinematographically, this meant: simple lighting, quick takes, few repetitions. The editing was brutal and efficiency-driven.
What distinguished an Oater from a regular B-Western was not primarily the budget—which was similarly tight for many productions—but the internal attitude towards quality. Oater producers preferred to calculate in feet of film per dollar. A horse chase scene was cost-effective, visually effective, and filled runtime. That's why these films also looked glued together: abrupt cuts between long shots and close-ups, reuse of stock footage from other productions, the same canyon location in five different films. As a DoP, you had to work with natural light, often in real dust or sunset, because there was no time for perfectly lit sets.
The Oater era (peak: 1925–1955) didn't disappear because quality became a problem, but because television took over this function. Daily soaps and Western series absorbed the viewers who had previously watched such quickies in the cinema. Today, the term is archaic, but in the industry, veterans still talk about an "Oater mentality" when a project is developed under time pressure and with a minimal budget—without artistic ambition, pure exploitation. The technical signature remains recognizable: rough cuts, pragmatic camera work, maximum output with minimal effort.