OH to be a writer on a film set.

When John Banville turned up to the Dublin house where Glenn Close was shooting Albert Nobbs he encountered a member of the crew.

Having asked where the filming was taking place, Banville, whose Booker-prize winning 2005 novel The Sea has now been turned into a new film, was met with "Why?" Even saying that he had written the script received a distinctly unimpressed "Yeah?"

Being used to the writer's life, Banville was not downhearted. For him, working with movie people, getting away from his desk in general, still feels like a treat, especially when something truly thrilling happens, like someone else making the coffee. Oh to be a writer, chapter two.

"Writers are solitary beings," laughs Banville when we meet at the Edinburgh International Film Festival, where The Sea had its premiere last year. "We sit in our rooms for two, three, four years, scratching away at this page, making a book, then we come out blinking into the light like moles."

The Sea, his 18th novel, is the tale of a grieving widower (Ciaran Hinds) returning to the coastal town of childhood memory. It still thrills Banville to see "flesh and blood" actors speaking his lines.

"The process starts with casting. Casting itself is an extraordinary phenomenon. I often want to say to people can you cast it first and then I'll write the script because characters change completely when you get down to physical appearance. You write a script and you have a vision of somebody who is very tall, then somebody quite short plays the part and it changes completely. It's always fascinating."

Having adapted his own novels, and those of others, the 68-year-old knows better than most the learning curve required. Especially when dealing with one's own novel, you cannot expect that it will travel seamlessly on to the screen, he says.

"Even if you could do it it would be unutterably dull because cinema is made out of light, in all sense of the word light. There is a lightness to a story on screen that is not there in a novel. You are moving from one medium into an entirely other medium and I like that process."

Though The Sea has taken nine years to go from page to screen, this is a hop, skip and jump compared to the trek of Albert Nobbs from stage play to screenplay. The transformation of the novella by George Moore could not have happened without the six times Oscar-nominated Close pushing for it, says Banville.

"It took about 15 years to get it done. I hadn't heard from her for about six or seven years then she phoned me up one day and said we're ready to go, we've got the money. I have nothing but admiration for Hollywood people, their determination and tenacity. She would not give up."

The meetings with Glenn Close were particularly memorable, particularly the first one in a "very fancy" hotel in Paris where Banville, Close, the producer and director holed up to hammer out a script.

"It was the first time I had met Glenn. Actors are extraordinary people. She was talking about some scene and said 'There's got to be weeping in this' and she just started to weep. Tears streaming down her face. The three of us were sitting staring at her, open mouthed," he marvels. "Just to be able to cry."

Albert Nobbs, the story of a woman passing as a butler in nineteenth century Dublin, was nominated for three Oscars, including make-up. Banville can testify to the jaw-dropping power of the latter. When Close approached him on set (yes, he did eventually get past that inquisitive crew member) he thought she was a little old man until she said, "Hello, John."

Born in Wexford, Ireland, in 1945, Banville was a child of cinema's post war golden age. There were three theatres in the town, all of them counting Banville as a regular patron.

"I love that period. I still regret the advent of colour. Those black and white, or soot and silver, movies in those days were very beautiful."

Colour films did have their compensations, though, as with River of No Return, the 1954 western with Marilyn Monroe and Robert Mitchum. Suddenly, all the nine-year-old Banville wanted to do was take care of Kay Weston, the spirited yet fragile singer played by Monroe. "I would lie in bed at night crying about my love for Marilyn Monroe. I suppose I was nine or 10."

The teenage years found Banville on the train to Dublin with his cousin to an art house cinema showing the likes of Antonioni and Fellini. He soon found another heartbroken heroine to love in Monica Vitti.

"I would sit there thinking, 'Oh, to be unhappy with Monica Vitti'," he laughs. "She was the most beautiful woman. This was always the trouble with me with Antonioni movies, they were supposed to be about the bleakness and the horror of life and here were these exquisitely beautiful people living exquisitely beautiful lives. I would think why are they so unhappy? If I were there I wouldn't be unhappy."

It is not just as a writer and screenwriter that Banville leads a double life. Throughout his career, no single job seems to have been quite enough to satisfy his imagination and need to write. He was writing in his free time, for example, while a sub-editor, and later a literary editor, on the Irish Times. Today, his publishing persona is divided between Banville the literary novelist and the more lucrative Benjamin Black, writer of mysteries. In the latter guise, his most recent book was a Philip Marlowe novel, The Black-Eyed Blonde ("a beautifully rendered hardboiled novel that echoes Chandler's melancholy at perfect pitch," said Stephen King no less).

Even as a crime writer, Banville is at once an insider and an outsider, scathing about the way some crime writing is heading.

"Everything on television and every novel now starts with some young woman being raped and slaughtered. I'm surprised that women aren't complaining more about this.

"Maybe I'm just old fashioned but the world I live in is not a world of serial killers. Of course these things happen, there has always been crime, extreme violence, but it is not the world I live in and it's not the world that the vast majority of people watching these series or reading these books live in either."

He misses the romanticism of newspapers of old and the craic of the newspaper office in full cry. "I always had great admiration for reporters. Not people with opinions but people who just went out and got the stuff." But novels and the screen are now his homes, and he is happy to be back there for The Sea. He told the director, Stephen Brown, that he had made a work of art.

"Of course that will put people off like nobody's business," he laughs, but holds fast to the view.

"Art now is an embarrassing term. It's like sex for the Victorians, you are not supposed to mention it. But what's the point of doing any of this if you don't aim to make a work of art?"

The Sea opens on April 18