Peter Jackson, seen in San Diego in July, shared details about his Tintin and The Hobbit projects in London, where The Lovely Bones has its royal premiere on Tuesday. ((Chris Park/Associated Press))

In London for the royal premiere of his new film The Lovely Bones, Peter Jackson nevertheless offered up some tidbits about two of his highly anticipated works-in-progress: his 3D Tintin film and The Hobbit.

The long-awaited Tintin film — which the Oscar-winning New Zealand filmmaker is producing with American director Steven Spielberg — has completed filming, Jackson revealed in an interview with the BBC.

"Tintin is great. It's made. The movie is cut together and now [we] are turning it into a fully rendered film. So the movie, to some degree, exists in a very rough state," he said, adding that it will take another two years of post-production work before The Adventures of Tintin: The Secret of the Unicorn is ready for theatres.

The long-awaited project — based on Hergé's comics about an intrepid young investigative reporter — was to have been a trilogy, but movie studio Universal withdrew its funding. The new film will be produced by Paramount and Sony.

The forthcoming adaptation is now to be one movie based on three Tintin titles: The Crab with the Golden Claws, The Secret of the Unicorn and Red Rackham's Treasure.

The motion-capture 3D movie stars Jamie Bell as Tintin, Andy Serkis as Captain Haddock and Daniel Craig as the villain Red Rackham.

Though Jackson praised 3D technology, saying it "only adds to the experience" of watching movies, he emphasized that his forthcoming two-part adaptation of The Hobbit — directed by Guillermo Del Toro — would remain a conventional project.

"Guillermo wants to shoot in 35mm, old-fashioned film," Jackson said, "which suits me, because he wants to keep it in the same space as the original trilogy."

He also attempted to quell fears about continuity between his award-winning The Lord of the Rings trilogy and upcoming Hobbit films.

"We're writing the screenplays with him, so in terms of the script, there is continuity," Jackson said.

"But Guillermo, being the director, will obviously take the script and interpret that and shoot his film. So that'll be interesting to see."

Jackson's The Lovely Bones, based on Alice Sebold's bestselling novel, tells the story of a murdered teen who watchs her family from the afterlife.

The film has its Royal premiere — attended by Prince Charles and the Duchess of Cornwall — on Tuesday evening in London, with Jackson and stars Saoirse Ronan, Susan Sarandon and Mark Wahlberg also in attendance. It is slated for theatrical release in January.