180 degree

The meaning

It is a basic rule that means that two characters should always have the same left and right relationship to each other. When a camera crosses the line 'axis' connecting to two subjects it is called "crossing the line". The new shot is called the reverse angle shot.


An example
This diagram shows an axis between two people and the 180 degree arc and the camera may be placed in the green airier. When cutting from the green arc to the red arc, the people would have appeared to have switched places on the screen. 








you can only brake the 180 degree rule is by moving the camera a long tracks wile filming.