Andrew Weisblum, ACE, was familiar with director Darren Aronofsky's work when he took on Black Swan, a psychological thriller about a ballerina who unravels as she dances the challenging role of the Black Swan. Weisblum was the visual effects editor on The Fountain and the editor on The Wrestler. I spoke with him yesterday about cutting Aronofsky's latest film: Black Swan, starring Natalie Portman as Nina, a tortured ballerina; Mila Kunis as her rival and love interest; Vincent Cassel as the ballet troupe's director; and Barbara Hershey as Nina's over-protective mother.

How did you prep for editing this movie?

Darren and I had some discussions about genre and editorial styles that would be applicable. We discussed psychological thrillers and horror films. With horror films, we were referencing scary moments to see how those moments were executed and what were the tricks of the trade. There was a mandate to always concern ourselves with Nina's subjectivity. We were concerned with when and how to cross the line between realism and impressionism and how to blur that line as much as possible.

I read that Aronofsky says Black Swan is a bookend to The Wrestler, since both of them are about people pushing themselves to physical and psychological extremes. Were there similarities with regard to the editing?

Darren as a filmmaker is interested in point of view, and getting inside a character's head. If that main character were to be able to recount everything that happened to him, it's how would he tell the story.  In editing, that was in terms of where you start and stop a scene and where your transitions are. It was less about connecting images or keeping it fluid, and more just about where his or her thought process was.

I understand you were actually editing on the set.  How did this work?

I cut the film on an Avid Media Composer with the DNxHD 36 codec, and our home base editing room was set up with Unity MediaNetwork. But I also spent more than half the shoot on the set using a laptop [with software-only Avid Media Composer] with FireWire drives. I was on set for all the dance sequences and all the horror beats.  We did that because the schedule was so pressured and Darren wasn't storyboarding, so we wanted to make sure we were covering all the bases. I could try things out, make sure that things would time out in a way, particularly towards the last third of the film when the ballet and the film merge.

Where did you do the edit?

We edited at a facility in Midtown called Sixteen19, in the Brill Building. Sixteen19 also has a proper screening room/DI theater with a high-quality 2k projector. This theater is hooked up to the same central Avid Unity that our cutting rooms and systems were connected to, so whenever we wanted to screen the cut on the big screen in a proper environment, all we had to do was go down the hall to the theater (if it wasn't already booked), open our project on the Avid in the DI theater, and press play! It was instantaneous and a really useful and exciting way for me and Darren to step back and see how the film was playing.

What ended up being the most challenging scene?

Technically, the most complicated scene was when Nina and Lily go clubbing. There's so much going on subliminally. There are 20 instances of Nina thinking she's seeing herself. We pushed it farther and went all out. Every image of that scene — which is 45 to 50 seconds with 1,000 images — is manipulated.  Frame by frame, we manipulated the environment so the backgrounds were a selective mix of things from her reality and her imagination. Things from Swan Lake are hidden in there. It's a crazy collage.