By Lawrence Pollard
BBC World Service arts correspondent
Jack Vettriano is not an artist for the art world. The public buys more of his images than of anyone else's, but you will have trouble finding him in public collections.
Vettriano is a self-taught artist
It would be hard to find an artist more scorned, mocked and abused by established critics. But it would also be as hard to think of another living painter whose images have spread so far round the world.
Vettriano's images are enigmatic moments from an imaginary, half-remembered movie. Whether from a windswept romance or a dark erotic thriller, these scenes intrigue with hints of a story that can't quite be worked out.
"I've set the scene, you build the story," Vettriano told BBC World Service's The World Today programme.
"What I'm trying to do is set up these little dramas. I'm like a film director who's only going to give you one shot, that's it, and it's up to you to finish the film on my behalf."
The look is film noir - sharp-suited men, glamorous women. The story is often enigmatic and erotically charged. Could it be the 1940s, the 50s?
Wherever they are from, Vettriano's paintings are from his imagination - a mix of memories of small-town dances, pulp fiction, gangster movies and romantic yearning.
Born in Fife in Scotland, Vettriano was the son of a miner and did not start painting seriously until he was given a paint box in his early twenties.
Teaching himself by copying his beloved Caravaggio and Monet, he finally sold his first original pieces in the late 1980s and adopted his mother's maiden name.
Now his most famous painting, The Singing Butler - sold by the artist for £3,000 in 1991 - could fetch £250,000 when it is auctioned by Sotheby's.
But strangely, Vettriano makes more than that each year from the royalties on its reproductions - the copies are worth more than the original.
"Maybe three million copies of that image as a poster have been sold round the world" Vettriano's dealer Tom Hewlett said.
"If you go almost anywhere in the world to a poster shop or a gallery, you will see an image of Jack's.
"People respond to the image, not the name. The poster and card companies pay us a royalty and do our marketing for us."
Total sales for all his work are about 15 million - and he has only been painting for about 15 years.
"It's popular because its romantic, its whimsical, its accessible," Vettriano said. "You could say it's safe - and I think that people like to sit on their sofa at night and just imagine they were that couple."
Vettriano put his art's popularity down to "escapism". "At the end of the working day, we all want to escape somewhere else. I've always wanted to escape into my paintings."
He admits he is not the most technically gifted of artists and has no interest in the avant-garde or being cutting-edge.
But with contemporary art dominated by conceptualism, his traditional narrative painting is quite out of fashion - he has been called derivative, pornographic, simple-minded and even accused of painting by numbers.
The painting Embracing was part of Vettriano's previous record sale
One critic told me he hated the work so much he could not bring himself to talk about it.
Vettriano has shrugged off most of the attacks - with one exception. "Someone wrote I was free to do what I liked so long as I understood they wouldn't take me seriously," he said.
"That got to me. Who do these people think they are?"
Veteran London critic Richard Cork does not much care for Vettriano's paintings - but does admit his success makes him a fascinating cultural phenomenon.
"I think the public turn to him with relief, thinking here's something they can understand, that they can take in almost at a glance," he said.
"That's actually one of the problems I have with Vettriano - speaking as an art critic - I feel that once I have glanced at it I've got it really, there's not much more to appreciate."
The Singing Butler is a little like the poster of the "Tennis Girl" from the 1970s, or the "Hunk with the Baby" of the 1980s - an image so popular as to defy simple analysis.
Vettriano's style of retro with a splinter of menace or mystery obviously strikes a chord.
And if you had the original of The Singing Butler on your wall, would it be diminished or enhanced by knowing there were three million copies worldwide?