Did early Westerns actually film at night or just close down the lens?

For night scenes in early Western films, did they actually film at night or just close down the lens? George Young Miami, Florida Our boss Bob Boze Bell has the answer: “In the old days, most movies, especially Westerns, utilized what’s called ‘day for night,’ which means they shot in the daytime but underexposed the film so it looked darker. Also, many old Westerns utilized sound stages for nighttime effects where they could control the light. “Today, with greater lens capacity, ma