When Garth Jennings first set out in 2000 to make his new film “Son of Rambow,” about his childhood obsession with video cameras and his adolescent attempts to remake “Rambo: First Blood” with his friends, he says he hardly could have anticipated the technological revolution waiting just around the corner.

Year by year, as Mr. Jennings composed “Son of Rambow,” the soaring popularity of digital cameras and digital projection became less a trend and more a revolution. As the prices of those cameras kept dropping, he watched as an army of amateurs chucked their VHS tapes in favor of digital videocassettes. And when Web sites such as YouTube became overnight sensations, he saw the ways in which private passion projects were suddenly being propelled into the public domain.

“It’s very weird, all the coincidences that have surrounded this film in the last year or two,” Mr. Jennings, who made his feature directorial debut in 2005 with “The Hitchhiker’s Guide to the Galaxy,” said recently. “The fact that another ‘Rambo’ movie came out, the fact that ‘Be Kind Rewind’ just hit theaters, that fan films are now a common thing to see on YouTube, the way that we finished ‘Rambow’ after getting the chance of a lifetime to direct ‘Hitchhiker’s’ and live out our childhood dreams — I mean, what’s next?”

Surely everyone at Paramount Vantage hopes “next” involves “Son of Rambow” becoming an art-house hit when it opens in New York next Friday. The movie became a crowd favorite at the 2007 Sundance Film Festival, prompting Vantage to win the bidding war with a reported $8 million. Since then, an array of movies about do-it-yourself filmmakers have hit theaters, suggesting that this homegrown theme has resonated profoundly in a culture obsessed not only with putting itself on film, but distributing the results to the masses. Mr. Jennings began dreaming of the project in a much different era.

“It was a long time ago now that I sat down with my producer, Nick Goldsmith, and I was talking to him about home movies, and it all started coming back to me — the way that I saw a pirated copy of ‘First Blood’ when I was 11 or 12 years old, and how my friends and I set out to make our own little action movie,” he said.

The more Mr. Jennings watched those old home movies, however, the more he found himself not just chuckling, but thinking seriously about what each video represented: a testament to the creativity, ingenuity, and liberation of childhood. So he set about writing a script about an isolated boy in rural England in the early 1980s who sees “First Blood” for the first time on VHS and assembles a crew of young filmmakers to do their best impersonation. After taking a lengthy break to direct “The Hitchhiker’s Guide to the Galaxy,” Mr. Jennings finished writing “Son of Rambow” in 2006, and arrived at Sundance in 2007 with a movie that had audiences laughing and cheering.

“Since then, I really have no idea why we’ve seen some similar stories pop up,” Mr. Jennings said, reflecting on movies of the past year and a half. “Maybe it will be like ‘A Bug’s Life’ and ‘Antz,’ which both came out during the same year — we sure would like to make as much money as those films did.”

Two do-it-yourself titles, in particular, have captured the imagination of New York moviegoers, one of which was the genuine article. Last year, “Raiders of the Lost Ark: The Adaptation,” a shot-by-shot re-creation of Steven Spielberg’s 1981 action film that took three Mississippi teenagers seven years to make, drew sold-out audiences to Anthology Film Archives. Painstakingly completed in 1989, the finished film was never meant to be seen by the public. But when a copy landed in the lap of the horror director Eli Roth more than a decade later, he passed it on to a glowing Mr. Spielberg, and it became a word-of-mouth sensation. Not long after, Paramount purchased the rights, and will presumably be making a real movie about a fake movie about a real movie.

Earlier this spring, Michel Gondry’s “Be Kind Rewind” found movie stars Jack Black and Mos Def as a pair of video-store clerks who are forced to act out their own, ultra-low-budget versions of such blockbusters as “Ghostbusters” and “The Lion King.” Though “Be Kind Rewind” was widely distributed and produced by a major studio, it gleefully traffics the modern idea of making your own movies when Hollywood doesn’t care who you are.

That’s why both films, as well as “Rambow,” are not all that much different from an array of fan films one can instantly access online. A YouTube search for “fan film” will find countless amateur interpretations of such movies as “Star Wars” and the James Bond thriller “Moonraker.” A grainy re-creation of the classic Nintendo video game “The Legend of Zelda” has been viewed more than 2 million times.

In the past, such manipulations of copyrighted material might have drawn lawsuits from major studios — particularly Viacom, which owns Paramount Vantage and has already sued YouTube for infringement. But in this era of such fan-propelled genre films as “Snakes on a Plane” and “Cloverfield,” it’s clear that Hollywood has embraced the profit potential of online fans spreading the word.

But, Mr. Jennings noted, what separates the ubiquitous fan films of YouTube from the amateur films he celebrates in “Son of Rambow” is a do-it-

for-yourself mentality. It’s an unexpected irony that “Son of Rambow,” which was conceived as a straightforward tale of nostalgia, has inadvertently become a timely commentary on the evolving face of film. When Mr. Jennings was a child, fan films were for the fans. Today, they are spoofs for the masses, made expressly to be Googled, YouTubed, and downloaded.

“When we did it, it was just for us,” the director said. “It was about us, seeing if we could do it. It was a lovely thing, to be making films and discovering yourself. It was about the doing, not about others seeing.”

ssnyder@nysun.com