ALITA: BATTLE ANGEL EXCLUSIVE Interview With VFX Supervisor Nick Epstein From WETA Digital

James Cameron and Robert Rodriguez's Alita: Battle Angel was one of this year's most pleasant surprises, and, despite a mixed critical reaction, the film was met with a warmer reception from fans across the globe, scoring an "A-" on CinemaScore and grossing over $404.8 million worldwide ($85.7M domestic; $319.1M foreign). 

To mark the film's arrival on 4K Ultra HD, Blu-ray 3D, Blu-ray and DVD today, we recently got a chance to sit down with WETA Digital's Nick Epstein, who served as the visual effects supervisor on the film, and learned a whole lot more about the making of the movie, Jim Cameron's response to the trailer backlash, and the process of turning Rosa Salazar into the ultimate hunter warrior.

ROHAN: Alita: Battle Angel was in at least some stage of development for nearly two decades before it actually became a reality. How early in the development process do you and your team get involved with starting work on the visual effects?

NICK EPSTEIN: Yeah, I think it varies from project to project. On Alita, we already had the history with Jim Cameron, working with him on Avatar, so I think we were approached fairly early on for this film. It was something that was already an established collaboration, so we knew that this was coming up.

We obviously just didn't know exactly when it was going to happen. I don't think anyone did until they made the decision that Robert Rodriguez would pick up the directing reigns and then the project moved forward, but generally, in a film like this, we get involved quite early on when there’s some pretty heavy character work to handle. We like to be involved as early as possible.

ROHAN: I’m sure you’ve been asked this a million times, but could you maybe describe the process of turning Rosa Salazar into Alita? Was it similar to your work on Avatar?

NICK: Yeah, well this could potentially be quite a long answer, so I’ll try and cut it down a bit to just the important parts.

We had a really great, beautiful performance from Rosa as Alita and so, I think a paramount thing for us was observing that performance through Alita. The tricky thing there is that Alita is a slightly stylized, magna-fied version of Rosa and that's not necessarily something your brain naturally accepts as being realistic. So, that was really the challenge for us, taking Rosa’s very, very real performance and making sure that the truth of that performance came across in Alita. So, it did make sense for us to base everything we did on the one constant that we did have, which was Rose.

Another tricky thing was that, for anything beyond Rose's performance, we didn't really have any real reference as to how a stylized face like Alita’s would move and talk in a realistic way, so, that was actually a fairly subjective process. Trial and error, that’s basically what we had to figure out as we went along - how we would best translate and make sure we maintained Rosa’s performance, butt sort of retarget it to Alita’s slightly stylized proportions.

There are a few things that we learned along the way, one thing of particular interest might be that we had a lot of difficulty with the mouth and making sure that we - I think we always thought that the eyes would be the most difficult thing we had to deal with, but actually maintaining Rosa's performance through the mouth was actually one of the harder things for us, but there’s a saying that sometimes the simplest solutions can be the best ones and we actually ended up taking Rose's digital mouth, the digital version of Rosa, we took the mouth out wholesale and put that on Alita to get rid of any non-proportional scaling of the mouth and that meant we pretty much had a one-to-one match between what Rosa was doing and what Alita was doing in the region of the mouth, which is where we had the biggest problem.

Same thing for the eyes, albeit scaled up. Alita’s eyes are obviously bigger than Rosa’s, but it's actually Rosa’s eye shapes in there and that was there to maintain the truth of Rosa's performance and getting rid of any non-proportional scaling, which was what was causing this issue.

That’s probably, you know, in a very, very brief nutshell, some of the things we did.

ROHAN: Was there a reason Jim or Robert gave you as to why Alita was the only main character to receive this manga-fied, stylized look, while the other Hunter Killers were basically just faces added to robot shells? I think Michelle Rodriguez’s character had a similar appearance as well, was it just to differentiate their kind of warrior robot versus the newer models?

NICK: Yeah, I mean, that’s probably more of a filmmaker-level question, but I think just personally speaking, it does help you realize where I think Alita comes from and the reveals in the move do ultimately make it clear why Alita looks the way that she does.

ROHAN: What was the most difficult sequence that you had to realize, outside of just creating Alita? I’m guessing the Motorball stuff proved to be challenging?

NICK: Yeah, there were a few pretty, pretty, pretty tricky things. I think the way that the work was broken down at WETA, any of us, who were responsible for a chunk of the movie, we probably all have our own war stories - I think the lake scene was quite, quite tricky in particular. Underworld was was tricky, but it was quite a fun sequence as well. We certainly got to explore capturing the heart of the manga and making sure that we were capturing individual beats and poses from the manga, which was pretty fun.

I actually, to be honest, from my personal experience, the hardest thing I had was the Kinuba (Leonard Wu) scene. When Kinuba comes out of the bar, he’s actually carrying two girls on his shoulders and that type of work where you've got to basically replace everything but the face and deal with hair and body interaction with live-action actors, that some pretty tricky work and all the subsequent shots where he’s on the ground and so on - everything that happens to him, that stuff was actually quite difficult.

ROHAN: Oh cool, I wouldn't have expected that.

NICK: Yeah, I think it's a pretty brief scene, it's over in about a minute or two, in terms of the whole movie’s runtime, but I think, in terms of personal war stories, that's the thing that stands out because it was actually really, really difficult. Some of the bigger things that we were responsible for, they were obviously hard too, but you sort of see that reflected in the runtime, like, for instance, Underworld played for six or seven minutes, so you see that, but when you do a really difficult scene that’s over in about a minute, that’s usually the thing that stays with you.

ROHAN: Was there any scene or sequence that you thought was really cool or had a blast working on and that you actually finished that ultimately ended up on the cutting room floor?

NICK: I’m not sure about if anything finished ended up on the cutting room floor.

I think the most fun sequence that I worked on was Underworld and you may have seen this in some of the marketing materials of how we were able to really explore capturing key beats and poses from the manga. That was a really, really rewarding process for us and actually being able to go back at the end and sort of compare the film to the manga and see how close we were able to get for fans fo the manga, like me and my animation supervisor, that was a really satisfying bit of the process.

ROHAN: With social media nowadays, we’re getting a lot more instant reactions to trailers, which usually feature unfinished effects, and how characters fans know and love from other media look in live-action. It’s been positive and negative, probably leaning toward the latter as we saw with Sonic recently, which resulted in the film’s director essentially going back to the drawing board to completely redesign the lead hero. I think we also saw a similar situation with Justice League when they had to remove Henry Cavill’s Mission: Impossible mustache just weeks before release.

If I remember correctly, Alita’s appearance in the first trailer also received a mixed reception, but you guys stuck to your guns and stayed true to Jim and Robert’s vision, which obviously turned out to be the best decision.

Would you mind sharing your thoughts on that divisive reaction, and what the process would be like to make such a big change so late in the filmmaking process?

NICK: Yeah, I mean, we didn't really have any really big changes in direction. Jim and Robert, they set out to make a live-action manga movie and I'm really glad that they did that. I think it ultimately really paid off. You can see differences in Alita's appearances between the first trailer and the second trailer. And yeah, I think that there was a fair amount of internet reaction, shall we say, from that first trailer.

So, after the first trailer’s release, we were discussing the eye size with Jim, expecting that we may get a note to reduce the size of the eyes and Jim’s response was actually “screw the haters, we’re going bigger,” and that wasn’t really an off-the-cuff, ill-considered statement - what he meant by that was that the ratio of the eyes needed to be more realistic, so we needed to increase the size of the pupil, increase the size of the iris, so that we didn’t have so much waste around the eye, the sclera basically, and we’ve done large-eyed characters before like Gollum.

He had huge eyes and the Na’vi have really large eyes. I think Jim knew we could do it, he just wanted us to correct the ratio so, that we had a realistic ratio in the eye and then, there was no problem in Alita having those big, large manga eyes. It's just that the ratio between pupil, iris and sclera needed to be more realistic, so that was, sort of, the main thing that we changed. And I think if you compare the footage from the first trailer to the second trailer, it's not a huge change, but just making that ratio realistic actually made a huge difference in your perception of those eyes.

ROHAN: Oh yeah, I thought she looked phenomenal in the movie.

Before we run out of time, I just wanted to quickly try my luck! I know you’re not allowed to say much, but was just wondering how your work on Avatar 2 and its sequels is going?

NICK: *laughs* Sorry, I’m not allowed to disclose anything for Avatar just yet, those are all filmmaker-level questions.

Get all the details on the Alita: Battle Angel 4K Ultra HD, Blu-ray 3D, Blu-ray and DVD release and watch the first ten minutes of the hit film by heading HERE!

From visionary filmmakers James Cameron (AVATAR) and Robert Rodriguez (SIN CITY), comes ALITA: BATTLE ANGEL, an epic adventure of hope and empowerment. When Alita (Rosa Salazar) awakens with no memory of who she is in a future world she does not recognize, she is taken in by Ido (Christoph Waltz), a compassionate doctor who realizes that somewhere in this abandoned cyborg shell is the heart and soul of a young woman with an extraordinary past. As Alita learns to navigate her new life and the treacherous streets of Iron City, Ido tries to shield her from her mysterious history while her street-smart new friend Hugo (Keean Johnson) offers instead to help trigger her memories. But it is only when the deadly and corrupt forces that run the city come after Alita that she discovers a clue to her past – she has unique fighting abilities that those in power will stop at nothing to control. If she can stay out of their grasp, she could be the key to saving her friends, her family and the world she’s grown to love.