With regards to camera rotation, why was 180 degree rule introduced to cinematography?
a.
Early cameras were difficult to move any more than 180 degrees around a subject.
b.
It helps to orient the viewer's perspective and stops them from becoming confused about the image or the location of the subjects or objects.
c.
Lighting could only be placed for 180 degree shots, otherwise the lights would show up in the final product of the film.
d.
It ensured that the faces of all the subjects in the film would be shown on camera.