In the world of filmmaking there are two “rules” which each share the same name. The 180 degree rule. One has to do with the position of your camera with respect to your actors/subjects. The other has to do with the relation of shutter speed and frame rate. Both “rules” are established to improve the viewing experience of your audience. I put the word “rules” in quotes, because like every other rule, they can be broken…if you know why you’re breaking it and it serves the story. However, IMHO, I see a lot of newbie filmmakers breaking these rules because they seemingly don’t know. So, I wanted to give two quick blogs posts on these rules and why you should keep them; and why (and when) you’d want to break them.
DON’T CROSS THE LINE
The first 180 degree rule I want to discuss is the 180 degree line rule. It states that if you have two subjects speaking to one another in a scene, draw an imaginary line through the middle of them. At all times, you need to keep the camera one the same side of the line. If you cross that line, you’ve “crossed the 180.” (And yes, that was the origin of the name for my podcast, “Crossing the 180: The Filmmakers Podcast that Breaks all the Rules.”) The purpose of the rule is to keep the audience properly oriented. If actor A on the screen is looking from left to right, and actor B is looking from right to left, they will be properly oriented as long as you stay on the same side of the 180 degree line. But, if for whatever reason, you move the camera around for another part of the dialog, and you cross that 180, then both actors will be looking from either right to left, or vice versa, as you cut back and forth. That will be off-putting to the viewer.
But it’s not just narrative films where this rule applies. You can apply it to event video or documentaries too. Let’s say you’re shooting a wedding, ideally you should keep the camera on the same side of the 180, using the bride and groom as the two subjects. If in a documentary you have two people talking and let’s say you’re shooting with two cameras, keep both cameras on the same side of the 180 for the same reason.
BREAKING THE RULE
Many newbies break this rule because they simply don’t know and aren’t aware. Many experienced people even break this rule from time to time because they may have had so many camera changes or are trying to get interesting angles, they forget where the 180 degree line started. Having a dedicated script supervisor (the person in charge of keeping track of how actors deliver lines, where props were for each shot, etc.) can help. But, I would bet many of you reading this don’t have that. So, you just gotta keep a mental note.
It usually makes sense to break this rule if you’re in a situation (usually an event video like a wedding) where you are forced to stand or set up your camera in such a way that it breaks the rule. Other than that, I can’t think of any other times I’d want to break this rule on purpose, unless for some reason I’m purposefully trying to disorient the audience. If you have ideas of when it would make sense to break this rule on purpose, please share in the comments.