The 180 Degree Rule

This is a simple principle. A lot of people don’t know what it is, but they recognize when it’s wrong. So, how to explain this…

The 180 degree rule is a line of action drawn through our scene. Now, pick one side of this line and stay on it. At least for the basics, try to stay on one side until you do it without thinking about it.

Imagine a table with a person sitting at each end. Their eye line is your 180 degree line. During a dialogue between these two characters the camera angles will generally be places over the shoulder of a character to face the person talking.

B is talking, the camera is placed over A’s shoulder.

When A reacts/responds, we place the camera over B’s Shoulder.

Bam. Done. The way to do it right in the most simple way. Now, how to do it wrong…

Now, if you go and shoot it this way, crossing the line like in the diagram, you’ll notice the person the camera is focusing on will end up on the right side of the screen facing towards the left. Follow the diagram and they’ll end up with the same framing. This will actually also make the characters appear to be on the same side of the table.

Now this is the basics of the 180. But it is still useful when developing an action scene. I’ll try to film a short sequence implementing the rule this coming week.

There are ways to break this rule and make it acceptable (as is the case with all rules.). To do so, the camera needs to move towards the line. This either needs to be a cut and the camera changes or be a physical move during the shot. If going with a cut, move the camera from the over the shoulder position (abbreviated OTS) to just on the line. If doing a physical move (like a dolly) then just approach the line and continue past it while still keeping the camera on the subject.

Now I want to talk about Psychological Mapping. The whole reason we do this whole 180-degree rule thing is to keep the audiences brain happy. Like I stated before, you notice when it’s wrong, not when it’s right.

What’s happening is your brain is building a mental map of the location and the people/objects within it. Filmmaking gives selective details that force the filmmaker to careful build his scene and shots. The better this is done, the happier the viewer.

Not only does disrupting the mental map jar your audience, it removes them from the experience of the story and makes them aware they’re watching a film.

I highly recommend planning every scene around this rule. Sketch it out if you need to. Just make it clear in your head before you begin shooting.