The Lord of the Rings The Two Towers is battling for six Oscars, and New Line Cinema had lobbied for more, including a nomination for Andy Serkis, the actor who gave voice and motion to Gollum.

Peter Calveley is one of the actors who provided the motions for computer generated elves and orcs in Two Towers.

But Peter Calveley would have been satisfied with just seeing his name in the closing credits. The New Zealander, 32, was one of more than a dozen actors who provided the motions of the films computer generated elves and orcs.

The studio and Weta Digital, the visual effects house co founded by director Peter Jackson, say that only so many people could be listed and that Calveley's contract did not stipulate a credit. But Calveley notes that he and the others, who were cloned into thousands by computers, were crucial to realizing Jackson's vision. Besides, caterers, payroll clerks, publicists and drivers got credits. "Just because they cover people with digital skins, they can't hide their existence," Calveley says.

Digital characters are an emerging issue in film. Several movies, including Final Fantasy The Spirits Within (2001) and The Polar Express, due November 2004, have eschewed real actors for computerized ones. A growing number of others have used graphic technology where once hundreds of extras would have been hired.

With "motion capture," or mocap, technology, actors' movements are digitized and applied to computer generated characters. The armies in Rings' battle scenes include thousands of orcs and elves, based on the work of performance actors.

As technology improves, digital characters are becoming more lifelike. "It's not difficult to see how this is changing the landscape of filmmaking," says Remington Scott, motion capture supervisor on Final Fantasy and The Two Towers.

Credit may be deserved, but no rules require them, says Jarrod Philips of L.A. based House of Moves, which has worked on films such as The Patriot and Men In Black II. "You have to have a performer generate a performance, so there is no reason it should not be credited."

Calveley acknowledges he should have checked his contract. The Screen Actors Guild plans to discuss the rights of digital character actors. "New technology is one area we are looking at," SAG's Ilyanne Morden Kichaven says.

Jackson added the names of several thousand Rings fan club members on the extended Fellowship DVD, so Calveley hopes he might get credits on future DVDS and theatrical releases.

For now, he hopes to educate others on the question. "The fact that an actor can perform once and be re used for a number of different movies, video games, TV series or even media that don't exist yet might give a digital performer food for thought before they sign that contract giving up all rights."