In the late 1970s, the photographer Nan Goldin began documenting hedonism and bohemia in New York City, chronicling the downtown lives of her friends and lovers with raw intimacy. Those images became a time capsule of a grittier city and established Ms. Goldin’s place as one of America’s most important photographers.

On Sunday, she is heading to the Oscars, where she’ll be surrounded by red carpet crowds and flashing camera lights.

Ms. Goldin, 69, is the subject of “All the Beauty and the Bloodshed,” a film directed by Laura Poitras that has been nominated for best documentary feature. It follows Ms. Goldin’s efforts to raise awareness about the opioid crisis and her mission to remove the name of the wealthy and philanthropic Sackler family, who owned the pharmaceutical company that developed OxyContin, from the walls of museums like the Guggenheim and the Louvre.

The film opens with Ms. Goldin’s action group staging a protest at the Metropolitan Museum of Art’s Sackler Wing, in which they threw prescription bottles into the Temple of Dendur’s reflection pool. The Met later changed the wing’s name.

Ms. Goldin started her campaign after undergoing rehabilitation for an OxyContin addiction that she developed after wrist surgery. In recent days she has been busy with the task of getting ready for the Oscars, hitting the racks of clothing stores and scouring 1stDibs for vintage finds. Speaking from her sofa in her apartment in the Clinton Hill neighborhood of Brooklyn on the afternoon before her flight to Los Angeles, Ms. Goldin shared her plans.

Are you ready for the big night?

I’ve always loved Hollywood and what the Oscars stand for in American culture and history. I used to go with my friends to watch the legendary movie stars like Barbara Stanwyck and Marlene Dietrich. Right now on my desk I have a copy of “Hollywood Babylon” by Kenneth Anger. I love the old pre-Code silent movies.

Who will you be wearing?

I met with the designer Elena Dawson for a fitting in London. It’s a red dress with a long train. She’s a young British designer, and I’ve been wearing her clothes for some time. I also have a green satin mermaid gown from Zac Posen. At the moment, I’m still deciding between those two for the red carpet, but I’m planning to wear everything and maybe some other things to the after-party and other parties.

I have an old black dress by Alexander McQueen. Prada gave me a suit, and I think Dior and Chanel are giving me something. Yesterday I bought some paste, which is a nickname for fake diamonds, and they were from Bergdorf’s. I checked out some things at the Albright Fashion Library in Cooper Square, which is a place where you can borrow gorgeous clothes.

So I haven’t decided everything yet, but I’m bringing some friends and I’ll be getting dressed with them in my hotel on Oscars night. I also like styling my friends.

What was the fitting like?

I was in London for the BAFTAs, where I wore Yohji Yamamoto. I love Yohji. And I was staying at the hotel, Hazlitt’s, so Elena came to do the fitting with me there. She uses lots of contrasting black and white and has an incredible way of using fabric. She understands the past and present. She’s also very independent, she has a little studio of her own.

There’s a tradition of fashion and activism on the red carpet. Is that something you’re considering?

There’s no message. I also have a sense of humor and I want to wear what looks good on me. That’s not meant to cut into the seriousness of the film. The Oscars have always had historical meaning to me. I’ve actually always wanted to make a movie. If I do, it will be a comedy.

If you make it to the podium, do you know what you’ll say?

I have no idea if I’ll be able to make a speech, but if I do, I’ll have something to say. Our film is important because it’s destigmatizing things that are still stigmatized in society today, like sex work and drug use. I want to keep speaking up on behalf of safe overdose-prevention sites. I want to keep people alive.

Do you care about winning?

I’m not a competitive person, and I never have been. What’s important to me is that the film is now an action unto itself. We’re an activist group that helped succeed in bringing down a billionaire family. And people are now talking about drug use and the de-stigmatization of it. The documentary is going to keep spreading the word louder than we ever can now.