What method is "better" for recording audio of objects (f.e. cars) in the distance coming into the shot?
Mic picking up sound from the camera's position or recording the sound from near by and then applying the effect in post? Any "rules" how those scenes get recorded?
The way that it's done in films with a sound post you go out and record a bunch of car bys, ideally with the "right" car. As a general rule you won't get a good sound from the same setup you will get the picture from.
For instance you don't want to record cars going fast, even if in the shot they are. Also lenses change the perceived distances in ways that a microphone can't.
and you can't easily make perspective changes in post, so you do want to record the type of perspective you will need.
What you always have to remember our job as filmmakers (or a member of one of the crafts) is to create a believable artificial reality.
Mics do not hear the way our ears do. Mixers do not process and recorders do not remember the way our brains do. And audio reproduction systems run an extremely poor second to reality. So we use technical artistry to transform all of this artificiality into something believable.