NEW YORK, NY.- When a movie is selected to premiere at a festival, it’s a time of celebration for the filmmakers. But it’s not an end to their labors.

Very often, there’s work left to be done on the movie before it’s unveiled to the world. While fans excitedly scroll through the latest showcase at an upcoming festival, some of the filmmakers might still be sweating over making their movies look and sound exactly as intended.

It’s all a normal part of the process when postproduction and festival calendars overlap, whether at the Venice Film Festival, which opens Wednesday and runs through Sept. 7, or at Cannes or Sundance.

After Venice announced its latest lineup, many filmmakers were still polishing the sound mixing, color correction and visual effects of their movies. In late July, Dea Kulumbegashvili, the Georgian director of the competition title “April,” was still completing aspects of her film about an obstetrician who performs illegal abortions.

Reached at Studio Babelsberg in Potsdam, Germany, she said she was waiting on around 10 shots with visual effects that needed to be finalized. She described the nature of the effects somewhat enigmatically as “a character” in the film that required a careful eye across many long-sequence shots.

“It was a bit funny how I thought it would be really easy to do,” Kulumbegashvili said. “It’s really meticulous work that they need to do. Even if you need to remove one thing, you need to wait for days until it’s done.”

On the particular day we spoke, she had finished editing the subtitles, doing an initial translation of the Georgian dialogue to English. Sound mixing, she said, had just been completed, which meant that the festival had viewed a “temporary mix” when considering the film. (And besides postproduction, life went on, too: She said she was also making time for her son, who was born after shooting concluded.)

Along the way, members of the production team viewed the film multiple times, including one fellow director.

“I did show the film several times to Luca Guadagnino, who’s also a producer,” she said. “And he was very helpful.”

Guadagnino has his own film in Venice, “Queer,” starring Daniel Craig in an adaptation of the William S. Burroughs novel. Craig Berkey, that film’s supervising sound editor, designer and rerecording mixer, was working on “Challengers” in 2022 when Guadagnino asked him to join his next project. The period drama, set in postwar Mexico City, involved details like sourcing the sound of the steam whistle that sweet potato vendors of the era used while pushing their carts down the street and sound-designing the surreal moments of the main character’s intoxicated visions.

Earlier this month, Guadagnino’s team was still making a few tweaks after finishing sound in Rome in July. But the director’s schedule revealed the sort of productivity necessary to stay on track.

“Luca was in London prepping his next film, so he would come on the weekend and we would do playbacks of what we had been working on during the week,” said Berkey, a multiple Oscar nominee for his films with the Coen brothers.

For “Pavements” — a multiform film about the canonical 1990s alternative band Pavement — the moment of acceptance to Venice added a defining urgency.

“It’s not like it’s panic — it’s a dream come true — but now we have very little time to get the whole thing done,” Robert Greene, a producer and editor for the film, said. “It’s like it’s not real until somebody tells you it’s real.”

Once again, mixing the sound is important, especially since it’s a music film, along with clearing rights for documentary material and awaiting a piece of tour footage from Lollapalooza 1995. But the color and consistency of the image is also a special task for this film, which uses split screens, and looks, as Greene put it, “like four D.A. Pennebaker movies edited into one.”

The work of a colorist is a technically exacting process that is not always well known, but without it, Greene said, the image looks “dull, less involving and doesn’t pop and doesn’t sing.” Ed Lachman, the Oscar-nominated cinematographer, shot another Venice film, the Maria Callas drama “Maria,” and described the final phases of postproduction as important for either preserving “the integrity of the overall look” or fine-tuning for a certain effect.

When picture and sound has been locked, the movie must be prepared for projection in Venice. That can mean creating and delivering (via either a download or a physical hard drive) a digital cinema package (DCP), which is the standard format for digital exhibition in movie theaters. But “The Brutalist,” Brady Corbet’s drama about a Hungarian Jewish architect in America, will screen in a freshly made 70 mm print.

FotoKem, a film laboratory and postproduction studio in Burbank, California, handles the creation — or “striking” — of the prints. Earlier this month, the team looked at Corbet’s film, which has a 215-minute listed runtime, in 10-minute-long units. At a certain point, the movie’s cinematographer, Lol Crawley, would come and review the print.

Andrew Oran, a FotoKem executive, estimated that “The Brutalist” would ultimately take up a whopping 13 reels, each around 20 pounds and contained in 18-1/2 by 18-1/2 by 7-1/2-inch boxes. (At one point during our call, Oran audibly grunted as he shifted sample reels around his office while estimating their size.) These reels were shipped to Venice by plane in advance of the festival unassembled — “cans on cores,” as Oran referred to them — and a projectionist at the festival will then assemble the film for projection.

(This was all in a day’s work at FotoKem: the striking of IMAX 70 mm prints for the general release of “Joker: Folie à Deux” in October and planning for postproduction on Paul Thomas Anderson’s next film was also underway.)

Reached again later this month, Kulumbegashvili said that she needed to check one more detail of the visual effects in “April.” Then it would be time to make a DCP, which she also would need to inspect.

Completion was in sight, and perhaps the premiere as well. But as it turned out, the secret to seeing things through was a little benign tunnel vision.

“I prefer to just work on the film and do as much as I can during the day for the film and not think about the premiere until it’s really happening,” she said with a laugh.

This article originally appeared in The New York Times.