No one likes rules, we all want to be “free” and follow just our “feelings”. So if our gut tells us how what is best for the particular scene, why bother about rules?
Well, what are in the end rules? Simply common patterns in the works of the masters. A new master creates new rules, respects old rules, breaks old rules, breaks even the rules that he/she created. It has been always like that, since the beginning of Cinema.

That being said, let’s talk briefly about one of those famous rules: the 180° rule.

The “180-degree rule” is a fundamental guideline in filmmaking and cinematography. It’s especially important for maintaining spatial relationships and orientation in scenes where two characters are interacting. Here’s a breakdown of the rule and its significance:

1. Imaginary Line: First, imagine a straight line (often referred to as the “axis of action” or “line of action”) that runs through the main actors or subjects of a particular scene. This line establishes a reference point that the camera should not cross.
2. 180 Degrees: Once this line is set, the rule dictates that the camera should remain on one side of that line, covering a 180-degree arc, for the entirety of the scene. If the camera were to cross this line, it would lead to a sudden and confusing change in perspective, often referred to as “jumping the line.”
3. Purpose: The 180-degree rule helps maintain consistent screen direction, so that characters who are looking or moving to the right in one shot will continue to do so in the next, and vice-versa. It ensures spatial orientation and consistency, making it easier for audiences to follow the action and understand the spatial relationships between characters.
4. Exceptions: While the 180-degree rule is a foundational guideline, filmmakers sometimes intentionally break it for artistic or narrative reasons. In such cases, the audience might feel a jolt or disorientation, which can be used deliberately to convey feelings of confusion or chaos.
5. Matching Eyelines: Another related concept to the 180-degree rule is matching eyelines. When two characters are talking, if one is looking to the right in one shot, the other should be seen looking to the left in the reverse shot, ensuring that the audience feels they are looking at each other.
6. Establishing Shots: If a filmmaker needs or wants to change which side of the line the camera is on, they often use an “establishing shot” or a series of shots that gradually move the audience’s perspective across the line without disorientation.

In film schools and on sets, this rule is one of the basics taught early on because it’s vital for keeping visual coherence in a scene. However, as with many rules in art, it’s essential to understand it fully so that if and when you decide to break it, you do so with intention and purpose.