Directed by Neo Sora, “Ryuichi Sakamoto: Opus” records the final performance of its namesake composer and musician prior to his death from cancer in March 2023. Per Sora, Sakamoto’s son, “Opus” is less a documentary than a concert film, capturing 20 tracks — electronic, orchestral, and everything in between — from his multifaceted career as they’re played on the piano in crisp black and white, in lighting that transitions from night to day and back to night.

As he explains, it was no small task to chronicle what he knew could be his father’s last artistic gift to the world. But when speaking about the film, Sora maintains a studied objectivity that focuses more on the process of making it than the feelings behind it — much less about his father in general. Even as a fan of Sakamoto’s since the days of Bernardo Bertolucci’s “The Last Emperor,” it’s unexpected to feel as a journalist like you’re more passionate about a filmmaker’s subject than he is. Yet Sora’s thoughtful practicality about the challenges of “Opus” belies the disposition of an artist perhaps unsurprisingly similar to Sakamoto, marrying a virtuoso control of technique and technology with intuitive inspiration for an end result that’s as powerful as it is precise. Lightly edited below are Sora’s thoughts about the film, which opens in New York March 15 with a national rollout to follow.

When you started, did you approach this as a filmmaker documenting a subject? Or did you approach it as a son documenting his father?

I don’t know if those things can be completely separated, but my intention was to do as good of a job as I could as a filmmaker to record this performance in amber, so to speak. But it was also not quite a documentarist’s recording a subject, because I definitely employed a bunch of fictional filmmaking techniques.

Did you feel a sense of responsibility, or was it something that was for you an act of love?

Obviously I have love for him and his music, but as soon as the filmmaking process started, I definitely feel the burden of making sure to have all the technical aspects correct, because it is a performance, especially in his physical condition, was something that we can only capture one time.

Were there any discussions that you and he had about an arrangement, or a selection of songs? I would not call it a “greatest hits” concert, but it definitely covers some of those.

There was a professional separation between his work and my work: for him, he’s the person who’s responsible for the music, and I’m responsible for capturing the music. But one imposition that I made as a filmmaker was to create and stick to the set list early, so that we could all prep for it. I had basically come up with this unifying concept of the concert will span from night to day back to night again. Ryuichi responded to that by reordering certain songs. Then the one thing that I asked for was that the final song of the concert was “Opus.” As a filmmaker, I get more moved by his music that has this extremely unaffected, quotidian feeling to it. “Opus” almost feels like Ozu films, where it’s just day to day, cutting from shot to shot of almost nothing — but then within the context of the whole film, it’s affecting. But he liked that idea, and so agreed to do it.

You mentioned Ozu. Were there any cinematic influences, or be it concert films, or cinematic influences in general, that you drew upon?

There’s obviously the stock of cinematic influences that has accumulated in my own life as a filmmaker, like Béla Tarr’s films or Taiwanese cinema, where the story is more in the details than a narrative. But in terms of specific songs, there’s “Solitude” from the film “Tony Takitani” that he plays. That film really is notable for its lateral tracking shots throughout the whole film, so we decided we would incorporate a little bit of that into the shooting of that song. But in general, what we always try to do between [cinematographer] Bill Kirstein and I, is to come up with whatever we feel is the necessary camera movements or shots to represent or express for a certain song. The reason why we wanted to shoot in black and white was to achieve this unifying idea of time passing in a day. Then also because we were thinking about the physicality of the performance, putting it in black and white, the texture of the piano and the texture of the skin on his hands almost become like one.

Ryuichi spent a long time deconstructing his relationship with the 12-tone Western musical structure. Though he’d done many retrospective piano concerts of his work, were there any of his songs that were more difficult for him to adapt to the instrument?

“Trioon,” which was originally a song that he and Alva Noto performed together, includes a lot of glitches and electronic sounds. With the piano, it’s really minimal, but the way that the piano [is placed] the space that he played it, and the way in which he plays it, really draws out harmonic frequencies. After a while, these kind of harmonic tones really start to sound a little bit like electronic tones. That’s something that he was really intentional about. “Tong Poo” was like a techno song [by Yellow Magic Orchestra], and in the film he plays it in this really slow way. And I remember there’s a section where he plays the main arpeggio over and over again, and when you play a piano note really low and then use the sustain pedal, it creates these harmonic frequencies again.

Was there a lot of after-the-fact identification in the editing of those sorts of details? I imagine detecting them took a very detailed-oriented approach.

I was definitely aware that’s something that we were going to capture. Especially in his last few years, even from the point of [the 2016 documentary] “Ryuichi Sakamoto: Coda,” he was really interested in the decaying of sound, and the undefinable moments where sound turns into silence. So that is something that the recording engineer, ZAK, was really tuned into, and really tried to capture. So he was putting mics in places that are really weird to try to capture those kinds of moments as the sound turns into silence and fades away. The other thing was that Bill and I were really careful about making sure that until the performance ends, everyone’s filming, so I was making sure to only call “cut” once the sound is completely gone. We really wanted to take any of his physical sounds — of the piano, but his breathing and his rustling and all that stuff — as part of the musical experience as well. So ZAK made sure to mic everything so that his physicality was also really present in the film.

What was your concept in including him stopping and restarting “Bibo No Aozora,” if it was more than just showing Ryuichi figure how to play the song in real time?

That’s a moment that I feel like is where “something happens.” I feel like as soon as the film starts to lull you into, “Oh yes, it’s a performance,” it wakes people up. But a little before this, I was filming him playing some music, and there were these moments where he would try to play a phrase and just wasn’t able to because of his physical inability. That to me captured everything about the story of the film. For the most part, he was able to play everything really well. [But] it really gives you a glimpse into the thought process that a musician or composer has behind composing. Because something goes wrong, and he just stops. But then he decides to take it as an opportunity to just figure it out, [and] the mistake actually frees him to do whatever the hell he wants for that moment.

When this was originally conceived, did Ryuichi look at it philosophically, or did he approach it from the standpoint of documenting him performing, knowing that there might not be another opportunity?

It was definitely talked about from the beginning that it could be the last performance, but also it’s difficult to know, obviously, because he wanted to live. I don’t know if he was really interested, or thought it was possible that one performance could capture his everything, because obviously it can’t. But I don’t know if you’re familiar with Glenn Gould, but there’s two recordings of the “Goldberg Variations” by Glenn Gould, one where he is super young, and one at the end of his life. Those two together really tells the story of his whole life, in a way. I feel like this film maybe is the position of the “Goldberg Variations” at the end of Glenn Gould’s life, where it’s not the best hits necessarily, but there are a lot of hit songs that he plays a lot. For example, “Tong Poo” is a song that a lot of people react to because they’re so surprised at how slow it is. But I feel like that captures his life, and aging, and all those things.

Were there moments during the performance that emotionally impacted you, whether it was with a memory of yours, or just something you associate with your father?

I feel like I should have a more emotional answer, but during the process of the filming, I was more concentrating to make sure we got everything. I was in a different room, a soundproof booth with all the camera feeds coming in on the screen. So I’m doing five things at once, and so it was really hard to actually be emotional about the music as you’re doing that. But Bill Kirstein and the two other camera operators were the ones that are actually reacting to the raw emotions of everything the most. My one big direction to that was to, “Just follow what you want to see, and how you feel yourself react the most.”

Knowing that this ended up being at least his final public performance, but knowing that it became that, do you feel a sense of catharsis or satisfaction of capturing this?

I have conflicting feelings about it. On one hand, I’m really happy to have been able to collaborate with him before he passed away. A lot of people have come up to me after screenings or film festivals, telling me, “My parent also passed away, and I’m so happy that you were able to do this with your father before he passed.” So I really realized that it’s a very rare thing to be able to have done something like that with your parent. On the other hand, I experienced this a lot with reading obituaries of him, that when somebody becomes narrativized, it almost “contains” the person within this thing that is finished. The fact that this film ended up being this conclusive final performance, in a way is similar to that kind of sadness, where I feel like, “Oh, it ended up containing him in a way as well.” But then again, something that I’m happy to have done with the film is to not have given it any documentary aspect, so that whenever anybody’s watching it, they can take from the film whatever they want, and that lets him continue to be interpreted in whatever way people want to.