Although he’s off-screen and rarely heard from during “The B-Side: Elsa Dorfman’s Portrait Photography,” there’s a moment when Errol Morris can’t help but squeal in delight when he sees a picture that he’s never seen before as Dorfman, his friend for decades, pulls out flat files of her 20” x 24” Polaroid photographs. Discussing images that are rare for how they’ve been produced on a large-format camera that few have had access to, but rarer still for what they capture, it’s telling that Morris leaves this pure expression of joy in the film, as if to act as punctuation on the pleasure he so effortlessly conveys of being in the same room as Dorfman, who will frequently refer to herself as a “nice Jewish girl,” yet recalls with each photograph a wild youth spent with Allen Ginsberg and Bob Dylan, among others.

The occasion for these recollections isn’t exactly a happy one – with Polaroid retiring her format of choice, Dorfman has little choice but to call it a career on the eve of turning 80, but “The B-Side” is nonetheless ebullient as the photographer presents one portrait after another, reminding herself of the moment in her life when she took it and often letting the pictures, brimming with life, speak for themselves. Although the film’s title may refer to Dorfman’s habit of taking two pictures for each of her subjects – one composed and the other freestyle, it could just as easily refer to how Morris eschews his trademark exacting visual style in favor of something with a looser, handmade feel, perhaps a necessity when the filmmaker had to hastily organize a shoot upon hearing news of the photographer’s retirement, but results in one of his warmest and most deeply satisfying films.

As Morris told me recently, “If there aren’t surprises, what’s the point of making a film?” and while he comes across plenty of his own in sitting down with Dorfman, “The B-Side” proves revelatory for fervent fans of the filmmaker. Now that the film starts its rollout across the country, he spoke about how he changed things up to profile his longtime pal as well as how he’s been affected by technological change himself.

Elsa Dorfman in "The B-Side"Did this feel like going back to basics?

I don’t think it’s back to basics, but it’s making a film with very little preparation, very little money, but deciding you’re going to make it and making it. I had known for a while I had wanted to make a movie about Elsa, but I didn’t know when I was going to make it or how. When I heard that she was moving these huge polaroids out of the house and had hired a moving company, I felt I should be there and I should record it, which I did. And that led to more filming, but it happened very quickly and all of a sudden, we found we had a film.

One of my favorite shots in the film is seeing Elsa’s husband Harvey at his desk watching as a large-scale portrait of him as a younger man passes him by quite literally. Was that the first day?

That was and we just followed them. We see them removing the first two huge polaroids from the wall — both a polaroid of Harvey and a polaroid of [their son] Isaac and then taking them out of the house, so yeah, that was day one.

You don’t use the interrotron. How did you decide how to film Elsa?

I certainly didn’t want the interrotron to be the only camera because it’s too restrictive in a way. In many ways, it’s not restrictive. It makes many things possible that would otherwise be impossible. But I liked the idea of capturing Elsa [in] the garage where she has all of the flat files [of her Polaroids] and somehow getting a feeling for that space and Elsa in that space. So I used a camera called the Revolution, which is a device I’ve used on commercials endlessly. It allows me actually to operate a camera, and there’s this shelf that runs the length of the garage. I put the Revolution on a camera head and operated the A camera myself. There were at least four cameras, maybe five, in the garage — [an] overhead cameras, then there’s cameras to the side and then the Revolution.

And [with] the Revolution, it’s very, very easy to manipulate the image, to dutch the image in particular. It’s a problem – it’s actually an interesting problem. How do you make a film about a photographer where the images are basically vertical? They’re portrait rather than landscape. Much taller than they are wide. You can’t put them in this band-aid shaped film frame because I wanted to shoot in scope for whatever crazy reason. And I knew I wanted to be able to sometimes seriously dutch the camera and I wanted to be able to manipulate it myself. I wanted in part to do my own camerawork. And it worked. From the beginning when Elsa starts holding up these photographs, it’s so strange because she would hold up the photographs in front of herself and [you] couldn’t see Elsa anymore, just her hands holding up the photograph to the top of her head and her voice from behind. It is a wonderful effect. And I thought to myself, I wonder if I shouldn’t do it this way, but the minute we started doing it, it felt very right, so we continued.

Elsa Dorfman in "The B-Side"You’re working on a series for Netflix and I understand when this film was submitted for Telluride, it ran about 40 minutes. In this day and age, is it interesting determining how long you want something to be?

It’s very different because it used to be everything had to be carved up into well-defined media chunks – [for] television with advertising, you knew that you had to have 23 minutes and you had to have a full half-hour if there was no advertising or close to it. Feature-length film had to be 90, 100, 110 minutes and now it’s a free for all. With streaming, things can really be any length you want them to be within reason. We knew with Elsa, if it was going to be released as a film, it had to be a certain length, but it works well at that length. I think there’s more freedom today about length and format, which is a good thing. It’s not a bad thing.

You can decide [what length] while you’re editing. As Elsa points out, we had no idea this was going to be a feature. This came as a surprise. A complete surprise? No, but we shot one day. We edited. That material was a certain length. We shot another day. Then there was more material and it got longer and longer and longer until suddenly, it was close to 80 minutes in length.

Since you were profiling another artist, was there anything instinctual you were able to bring to it in that sense?

I think it brings a lot to it. I’m not sure exactly what. Elsa was incredibly open in the sense of all this material that was in her house and she allowed us to go through everything. She thought she had lost the last tape of Ginsberg on the phone machine, telling Harvey and Elsa that he was dying. We found that. We found that old movie of Elsa roller skating. We found a lot of things and that would’ve been impossible without Elsa’s complete cooperation, so she was a real trouper.

You bring in the music of Jonathan Richman and the poetry of Allen Ginsberg, who are obviously two close friends of Elsa’s. Was there any significance to what works of theirs you decided to feature?

Of course there’s significance to them. I knew Allen Ginsberg through Elsa and Harvey and the Ginsberg poem [“America”] has enormous resonance today. It registers a disappointment in America and is an extraordinarily powerful poem and becomes even more powerful as a result of the last year, even more resonance. And Jonathan Richman has been a friend forever, and he wanted us to use that music. He’s the one who urged us to use it and he came to Telluride because Elsa came to Telluride with me with her posse – [the] people who run the camera with her – and we had the camera there – my wife, myself in addition, all the people involved in my office in the making of the film and there she was taking polaroids, it was terrific.

Has preserving Elsa’s work in this way been meaningful to you? Beyond telling her story on screen, I imagine you had to digitize some of the photos in order to present them onscreen.

Well, I would love Elsa to get her archive. I would hope that the film in some small way can bring enough attention to Elsa and her work that she will have people who want to take these photographs and preserve them. And I think it will happen. I’m increasingly optimistic that this work will just not be destroyed.

Elsa Dorfman in "The B-Side"This also is an interesting film from a technological standpoint [since] I think of you as such a technologically savvy filmmaker, but this seems nostalgic for this past format. Do you actually feel something’s lost in the name of progress?

Something is always is lost, but often something is gained. The Polaroid deal is different from filmmaking in the sense that yes, I’m still able to make films. Do I shoot with digital cameras? Yes, I do. I occasionally shoot on film, but very rarely. Do I still like film? Yes, I do, but everything is moving away from Kodak color negative to digital media. And I like it. I remember when we were making “Fast, Cheap and Out of Control,” we were shooting on multiple formats — reversal 16, reversal 35, color negative 35, 16, super 16, super 8, straight 8…I don’t know. There might be 20 different formats for that movie. You could’ve never edited it without turning it into digital media and putting it on an AVID. It would’ve been impossible. So there are things that you gain and there are things that you lose. For Elsa, though, it’s an entire world that came to an end when they closed Polaroid. The process of being with Elsa and the camera, taking the photograph, watching the photograph develop, the whole community experience of being there with Elsa and the camera, that’s lost. That’s not even the same thing as a large-format camera or a digital camera. It’s different. And perhaps that can never be recovered. But we go on.

There’s a great moment in the film where you scan over the family portraits she’s taken and it appears you’re in there…

We put it in there. It’s not completely by chance.

Has it been a family tradition to get your portrait taken?

Yes. We have probably close to 30 Elsa photographs. We have a lot of them. And I’m grateful for every last one of them.

“The B-Side: Elsa Dorfman’s Portrait Photography” is now open in Los Angeles at the Laemmle Royal and New York at the Angelika Film Center and the Elinor Bunin Film Center. A full list of theaters and dates is here.