Woody Allen takes my call lying on his bed. He's not unwell. On his bed is pretty much where he lives. It's certainly where he works.
"I don't have a study," he explains, in the kind of serious tone that a portraitist might discuss the relative merits of natural and synthetic bristles. "I work on the bed and in the corner of my bedroom is a table with a lamp on it and my typewriter and paper.
"It's comfortable. I lie on the bed and write and it's very relaxing. I write in longhand and after a few days go over to the table and type up what I've written and then come back to the bed and write some more."
Did he just say "typewriter"?
"I have the same typewriter that I have had since I was 16 years old," he says. "A man came to my house and sold me an Olympia portable for $40 and I've typed everything I've ever written on that.
"I have nothing philosophical against computers but I don't have an iPad or a computer. I have never been comfortable with any of that. The typewriter works for me."
Work it certainly does. Since (and including) Take the Money and Run in 1968, the man born Allen Stewart Konigsberg in Brooklyn in 1935, has written and directed 44 feature films - an output of one a year. He has acted in more than half of them, mostly in the main role. It's a staggering level of productivity and Allen, who turned 77 on December 1, shows no sign of letting up. A new film, which will star comedians Andrew Dice Clay and Louis CK, is in the works.
"Well, I'm active," he says by way of shrugging explanation. "So far my health has held up. My father lived to 100 and my mother to about 96, and I do a lot of things: I play with my band (an accomplished clarinettist, he has played in a New Orleans jazz band in a New York bar every Monday night for more than 30 years); I write for the New Yorker magazine; I work for the theatre. I keep doing things. When I finish a film, I move on. I can't sit around the house - I'd get bored.
"I take notes all the time when ideas hit me and I throw them in a drawer so I have a drawerful of ideas and I could probably make a lot more films."
To his legions of fans, that will come as good news. They're an odd bunch, Allen fans, much like Bob Dylan fans: they've been variously enthralled and disappointed over the years and seldom agree on which films enthralled and which disappointed. But they keep coming back for more.
The film-maker's creative direction took a sharp turn in 2005 with the release of Match Point, a thriller set in London. Allen had always been synonymous with New York and famously reluctant to leave it: September (1987), set in leafy rural Vermont, was shot entirely on a Brooklyn soundstage. But in short order, he has made three more films in London (Scoop, Cassandra's Dream and You Will Meet a Tall Dark Stranger); Spain (Vicky Cristina Barcelona); and France (Midnight in Paris).
His newest film, To Rome with Love, a series of unrelated vignettes set in the Eternal City, opens in cinemas here on Boxing Day.
"When I wrote Match Point it was set for New York but I got a phone call from London offering funding if I made it there. And it was a very pleasant experience. My family went with me for the summer and had a lovely vacation. The same thing happened in Barcelona, Paris and Rome."
The fact is that one of the most iconic American film-makers has a lot of trouble raising American money.
"I can find people to put up money," he says, "but in the US they want to read the script, they want to know who I'm going to cast. They want to be involved.
"In Europe they know right away that they can't read the script, that they can't have anything to say."
Allen's long-time American producers, Jack Rollins, who is now 96, and Charles H. Joffe, who died in 2008, famously never even knew a film's title until the director delivered the finished work. Working titles were Woody Allen Spring Project and suchlike.
It bears saying that Allen is probably unique among writer-directors (that is, film-makers who do not also produce) in having such complete creative control.
He describes it as good luck - "If you do comedy it has a sort of undeserved mystique; they have the feeling that 'he has the knack of being funny and we don't' so they leave you alone" - but it's good business too. Allen works on modest budgets and his films make modest returns: but they make consistent returns, which is rare in the movie business.
"(Producers) know that they probably won't lose money with me, after DVD and television and so on," he says, "and if, God forbid, they do, they will lose so little that they won't really notice it."
More than most film-makers, Woody Allen is routinely identified by audiences as being indistinguishable from the characters he creates and often plays: the neurotic nebbish of the early stand-up years, the mother-fixated son of New York Stories; the Alvy Singer of Annie Hall, desperately depressed because the universe is expanding and is going to fly to pieces. But he scoffs at the idea that he is what he writes.
"Those traits are in me, of course, but they are hugely exaggerated to make them funny or interesting.
"They are like a distorted cartoon; it's not really me.
"In real life, I'm competent, quiet, hard-working. I lead a very normal life. I'm not the crippled neurotic I play on the screen. If I were like that I would never be able to sustain a marriage or get any work done."
Allen once said that he has one of two reactions to the footage he has shot when he begins post-production: One is, "Okay don't panic"; the other is, "Actually, it's not as bad as I thought it was." I ask him which reaction he had to To Rome with Love.
"Well, I never make a film that I'm not disappointed in," he says. "I know directors who invite me to screenings of their films and they sit in the screening with me and say to me 'Isn't this terrific?'. I never feel that way. I always feel at the end of a film 'My God, I started out to make such a wonderful movie and look what I've turned out here; look how many mistakes I've made and how terrible it is'.
"That's why I never look at my films again after I finish them. I haven't seen the first film I made, Take The Money and Run, since I finished it in 1968. I would only see the mistakes and it would be a mass of self-flagellating regret. I'm better off just leaving it.
"I feel like a chef who makes a meal: somebody else can eat it."
Who: Woody Allen, veteran director
What: To Rome with Love
When: Opens Boxing Day