Hollywood is up in arms over a newly implemented campaigning rule -- not for politics, but for Oscars.

The Motion Picture Association of America recently banned movie studios from sending "screener" copies of their films to Academy voters in an effort to thwart piracy. The controversial move is causing waves in Hollywood, especially among studios with independent films to promote, who say it limits their ability to vie for awards.

“For the big studio movies, [being able to send screeners] is a nice added benefit for movies that already faded,” said Greg Kidlay of The Hollywood Reporter. “But for the smaller movies that are really jostling each other for attention, it’s much closer for a make or break situation.”

But how does the ban affect average movie viewers? Experts say the public won't likely notice a change at the movieplex next year, but down the line there may be fewer movie choices.

"If people don’t see these independent movies ... in the long term it could result in fewer of them being made," said pop culture expert Bob Thompson. "Even a nomination for an Oscar can be very, very important for these smaller movies."

On Friday, nearly 150 directors including Robert Altman, Martin Scorsese, Francis Ford Coppola and Robert Redford signed on open letter to Jack Valenti, head of the MPAA, urging for repeal of the screener ban. 

"Many great films, and in particular films that take risks, rely on critical acclaim and, when the film is fortunate enough, Academy consideration to reach a broad audience," states the letter, which appears in the trade paper Variety on Friday. "The MPAA decision to ban screeners irreparably damages the chances of such films: films that already have a difficult enough time finding financing and distribution. ...

Studios use ads, private screenings and parties to get the word out about their films. They also send out thousands of DVD and VHS copies of the films to Academy voters to be watched at home. Eliminating the screener option could seriously hamper small films from being seen, said Thompson.

"With the big movies people will have seen them anyway," he said. "If you take away screeners, you take away the possibility of those movies getting seen and possibly of giving those movies a boost. Ultimately, this could lead to fewer of these films."

Getting an Oscar isn't just about the honor. It's often about making a profit, having a longer run in theaters and widening distribution, factors more crucial to indie movies than to major studio films.

"For a big film like 'The Lord of the Rings: Return of the King,' we know it will make multi-millions of dollars. Oscar nominations and awards would just be frosting on that cake," Kidlay said. "On the other hand, for a smaller film like last year's 'The Pianist,' they can really add dollars to their bottom line by getting Oscar nominations."

Critics of the ban have accused the MPAA of favoring big movie studios, which have lost many Oscars to independents like "Fargo," "Pollock," "Monster's Ball" and "The Pianist" over the last several years.

But without the screeners, smaller Oscar hopefuls like "American Splendor" and "Lost in Translation" could be overlooked.

"When every Academy member can view all the films in contention, then it's a fair and even playing field," said "Moonstruck" director Norman Jewison in a letter to Valenti. "However, when the small independent film, which depends on its artistic appeal rather than wide commercial distribution by an MPA member -- is now denied access the playing field becomes unfair and uneven."

The screener ban announced by Valenti was agreed to by the group's members -- Disney, Warner Bros., Sony, Universal, 20th Century Fox, Paramount and MGM -- plus their affiliates such as New Line, Miramax, Focus Features and Sony Pictures Classics. DreamWorks, though not an MPAA member, also agreed to the screener ban.

"We know these screeners are a small part of piracy, but I aim to close every kind of hole in the dike I can find on piracy," Valenti said when he announced the new rules, adding that screener copies have turned up for sale on Internet sites such as eBay and also popped up in Asia, where they have been used to duplicate counterfeit DVDs.

The movie industry has not been hit nearly as hard by piracy as the music industry, but studios want to throw up as many roadblocks as possible before the technology catches up with them. Experts say the ban is a double-edged sword.

"You have two forces that are colliding here,” said Kidlay. “The industry’s determination to fight piracy and on the other hand, its eagerness to win Oscars and increase box-office take."

But not everyone is so concerned. Robert Downey Jr. told Fox News people should reserve judgment until they see what the consequences are.

"Everyone is assuming that it is going to hurt this or do that,” said Downey Jr. “Those are assumptions. Who knows? You never know what is going to happen.”

Fox News' Mike Waco and Marla Lehner contributed to this report.