‘It’s great exercise, making short films,” the actor and filmmaker Matthew Modine said recently. “Making a kind of sketch that gives an impression and entertains and delivers something in a very short time presents its own difficulties. In some ways, it’s more difficult than making a feature because of the limitations.”

Mr. Modine knows of what he speaks. In addition to storied and varied acting roles, from Private Joker in Stanley Kubrick’s “Full Metal Jacket” to Sullivan Groff in Showtime’s “Weeds,” Mr. Modine is the writer and director of multiple short-film projects, one of which, the 7-minute “I Think, I Thought,” unspools in competition at the Tribeca Film Festival five times before the big show folds its tent on May 6. This year, Tribeca will present 79 narrative and documentary short films, some organized into 11 separate thematic groupings, and others paired with features.

Screenings of short films at film festivals and film schools alike always offer plenty of evidence that making a successful short is not a simple endeavor. Overreaching long-form artistic ambitions can imbue a narrative short with a kind of conceptual desperation. The Japanese-born filmmaker Hyoe Yamamoto, whose “When I Become Silent” will play in the same program (entitled “Cold Feet”) as Mr. Modine’s film, chalks it up to careerism.

“A lot of people, including myself, want to get a feature film off the ground,” Mr. Yamamoto said. “There’s always an aspect of making sort of a business card, I think. You make a short film and you hope someone notices it and likes it and will want to work together on a feature film. At least, that’s the idea.”

But Mr. Yamamoto, himself the maker of four highly praised shorts, one of which, “At Night,” made its debut at Tribeca in 2004, is also quick to point out where the responsibilities of a short-form storyteller really lie. “It’s more a matter of doing it because you have something to say rather than making a business card,” he said. “You’re making it because it’s something you want to do.”

Mr. Modine agrees. “It’s always ultimately about the story, isn’t it,” he said. “It’s kind of like songs. If you’re compelled and interested in the melody, or in the case of a film you’re interested in the characters and what’s going to happen to them, the film will usually tell you how to cut it and what works and what doesn’t work.”

In the last decade, computer editing and non-film formats have radically democratized filmmaking of all running times. So much so that Mr. Modine, who grew up working in a drive-in theater owned by his family, compares moviemaking before and after the digital revolution with the defining creative threshold that separated black-and-white from Technicolor. “Literally anybody that can afford a pretty good camera and an editing program from Apple can shoot and make a film,” he said. “You don’t need all the lights; you don’t need all the crews.”

The freedom that digital liberation offers has also changed the “business card” creative paradigm, as homegrown filmmakers pool what resources they have to make ultra low-budget features in lieu of shorts. The writer and director Craig Brewer, for instance, gained traction for his multiplex debut, “Hustle and Flow,” via a digital feature, “Poor and Hungry,” which was made for the price of many NYU thesis films a third its length.

“People tell me that I just haven’t come across the material that I could do on such a shoestring budget and yet not compromise too much,” Mr. Yamamoto said. “I feel like it’s such a pain to go through three or four days of shooting when you’re doing a shoestring thing and you’re asking for a lot of favors. Just physically it’s very tough.”

As cable networks such as the Sundance Channel and IFC continue to greatly curtail their short-film acquisitions, the other side of digital filmmaking — exhibition as downloadable content via the Internet and other electronic means — has come into sharper focus. “In Japan, now cell phone movies are kind of in fashion,” Mr. Yamamoto said. “Some people that I spoke to in Japan especially seem to think that it’s going to be a golden age for filmmakers because a lot of companies are looking for content for cell phone broadcasting and Internet broadcasting and stuff like that.”

Mr. Modine, who this week inked a deal with iTunes to distribute “I Think, I Thought” via download, is understandably enthusiastic about Web sites such as AtomFilms, which acquire film content under a revenue-sharing system based on the number of visits to their advertiser-sponsored pages. But, like Mr. Yamamoto, he remains in the grip of an affection for short-form storytelling born of a longer view.

“There’s a great tradition of short filmmaking going back to the beginnings of film,” he said. That tradition extends to many of the feature directors with whom Mr. Modine has worked as an actor, including Stanley Kubrick and Robert Altman, as well as such renowned directors as Steven Spielberg, Martin Scorsese, and Clint Eastwood.

“One of the first directors I ever worked with, Noel Black, directed a short movie that played at the Cannes Film Festival and was nominated for an Oscar,” Mr. Modine said. Indeed, Mr. Black’s 1965 “Skaterdater” is a marvelously compact, visually poetic, and narratively frugal model by which to measure any filmmaker’s mastery of the short form. It is perhaps worth noting, however, that Mr. Modine first became acquainted with the film at what could be called the opposite end of the exhibiting spectrum that he has lately put to such good use. Unlike “I Think, I Thought,” “Skaterdater,” which exists in rights limbo, is not coming soon to a cell phone near you.

“I saw it at my dad’s drive-in,” Mr. Modine said.