I always wondered that as well Anita.
I think it just gives a perspective on things. The party scene with the Joker could mean that mwhen eh gets closer, everything spins out of control literally, your control is out of your hands now that he's here. You're world is spinning at the presence of him.
With the rooftop scene with the three, it plays well with the tension.
It may just symbolize the loss of control and the confusion of the situation. Whenever you see the 180 degree camera angle, it's always seems to be like that.
The spinning camera isn't really an example of breaking the 180 rule. I mean, sure it crosses it, but there isn't a distinct cut and the disorientation isn't in the cut itself, it's in the movement of the camera. Cuts that cross the 180 line are disorienting since it's difficult for the audience to figure out immediately what the geography is.
I've always been impressed with the spinning camera around Rachel/Joker choreography. It starts in one direction, reverses, settles on a 180 line, starts moving again, then comes to a dead stop on a side shot of the two just as Joker says, "One day they carve her face." Forget about the hospital explosion, how many times did they have to practice
that?
In addition to the interrogation scene, they also cross the 180 line (which is between Wayne and Dent) during the fancy dinner scene early on the movie. The camera even starts to drift towards the line before it crosses, when Natascha says the word "vigilante." (The drifting is probably how they're able to get away with breaking the 180 rule.) The camera then crosses several times for closeup shots of Wayne and Dent before panning out to a crossed shot of Wayne offering the fundraiser.
There are like, a billion different shots and angles in that scene. It's awfully complicated for a scene over a dinner table.
As for the interrogation scene, it crosses first when Batman asks, "Where's Dent?" It crosses again when Joker says, "To them you're just a freak. Like me." In both cases, it could be an attempt from each character to take control of the situation and shift it to their liking. Of course Joker's in control the whole time, but anyway.
What's really fascinating is how deliberate this all is. They knew how they were going to shoot this and where to place the camera each time. I don't know how far in advance Nolan and Pfister organize their shot lists, but something tells me they don't shoot from EVERY possible angle (even ones that break filmmaking rules) when doing a scene.
