The 180 Degree Rule

The master producers follow an established set of rules for a reason - to move the story along in a logical way that won't confuse the viewer. There are many things that we "know" about movies simply from having seen lots of them. We "know" for example that when the camera pans across a vast expanse of city and zooms in on a sign on a building that says International Widget, that the action that takes place after the cut is happening at International Widget. There are a number of rules we all know subconsciously even if we've never been told them. The 180 degree rule is one of them. The rule states simply that when filming (or videotaping) two elements (people, cars, armies, sports), the camera should stay within a 180 degree field and not "cross the line".

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