Todd Vaziri: Let’s Talk About The 180 Degree Line (Transcript)
One of the first things you’ll learn about when you start studying film making /visual storytelling, is the 180º line. There is a better explanation below, but so summarize there is an invisible line between characters and if you cross it in between shots it will disorient the audience.
Because of this disorientation you should avoid crossing the line at all costs. Or should you? Sometimes it might actually work really well to cross the line, if your intention is to disorient, or shock the audience. There are many great examples of this throughout film history.
Another option is to cross the line within a shot, to move the camera from one side of the line to the other in a single take. This is a really great way to visualize a change. It can be a change in relation. Maybe you want to show a change in power dynamic? It can also be used to show that a character gets a very important piece of information, that changes how he sees things. In one of my all-time favorite films, Heat (1995) this technique is used to show a very reserved character opening up.
On Twitter VFX artist Todd Vaziri analyzed this moment. Back in 2008 he spoke about a similar effect in Mission Impossible III on his blog. Below I’ve compiled, and slightly edited, his twitter thread and fragments from his older blogpost:
To establish a sense of orientation and understanding of a scene, particularly a scene with two characters talking to each other, the camera needs to stay on one side of the imaginary line that is created between the two characters. The camera, even within shot-reverse-shot sequences, needs to stay consistently on a single side, so that the scene is grounded for the viewer. The result: the audience is constantly oriented and understands the action.
If the camera moves to the other side of that line, especially in a cut, the audience is immediately disoriented. "Our hero has just spent the entire scene talking to a character to the left... and now our hero is on the right? Wait, what happened?" This can be used for dramatic effect, but in traditional Hollywood narrative filmmaking, this practice is frowned upon.
However, if you literally show the camera breaking the line in an uninterrupted shot, you can set up a new orientation of the scene properly. Plus, emotionally, the break of the line causes the viewer to realize that something is changing, something is different, something is disorienting
Let's talk about one of my favorite examples of a narrative use of crossing the line from HEAT (1995).
Seated at a bar, Eady starts a conversation with a guarded McCauley. The camera uncomfortably shoots this icy talk from behind the bar. McCauley lowers his guard, apologizes and introduces himself. The camera crosses the line and stops on the other side of the bar (the line).
The rest of the sequence is shot from the other side of the bar, with clearer views of their faces, as their relationship begins. The 180° line was purposefully crossed, marking an emotional shift in the sequence; awkward and off-putting replaced with warm and cordial. Additionally, it appears the actors were lit with warmer light in the second half of the sequence, as their relationship warms.
In summary, you can learn a lot about movies by watching "Heat" (1995).
