Surrounded by thousands of reproductions on the walls of student bedrooms, cafes and hospital corridors, it’s easy to lose sight of what Vincent Van Gogh’s paintings actually look like: the brushwork, the paint, the expressiveness. Nor quite how many paintings he actually produced – more than 860 in just nine years – beyond the well-known sunflowers, wheatfields, cafes and woolly-necked self-portraits.

But giving Vincent a run for his money – in terms of output at least – is a new film by artist, writer and director Dorota Kobiela and co-director Hugh Welchman, that literally paints the imagined story of Van Gogh’s last days. It’s an extraordinary concept. “Everything was a painting on canvas,” says Welchman. “No tracing, no nothing. The opening shot, where we come down from Starry Night, took six hours per frame to paint. So you’re talking about two weeks to do a second. It might have taken 20 weeks to paint that 10-second shot – you’re looking at half a year of someone’s life.”

The very idea of painting an entire feature film, frame-by-oily-frame, makes the palms sweat. But the result is bewitching: part exhibition, part whodunnit, with a cast that includes Douglas Booth, Helen McCrory, Chris O’Dowd, Saoirse Ronan and Aidan Turner. The process, according to cinematographer Tristan Oliver, may well be unique; the entire script was shot in live action in 14 days, on partial sets and in front of green screens at 3 Mills Studios in London. This footage was then handed over to a team of over 50 painters in Gdansk, who meticulously turned each frame into an individual painting. In the end, the team produced more than 65,000 frames in oil paints, on more than 850 canvases.

Loving Vincent review – a dreamlike, hand-painted plunge into Van Gogh Land Read more

“It’s all painted with Royal Talens paint brand called Van Gogh,” says Welchman. “It was sort of an accident, but that ended up being the best. We were ordering quite a lot of paint; around 3,000 litres.” No paint, however, could cope with the need to prevent the pictures drying out, so the team came to a surprising, somewhat fragrant solution: clove oil. “Clove oil was the big secret of our production,” says Kobiela. “We ended up mixing it with the paint. And it meant that the studio didn’t smell of disgusting turpentine but of beautiful cloves.”

The film’s plot focuses on a simple errand; the delivery of one of Van Gogh’s last letters to his brother Theo, after the painter’s death. What follows is an intriguing journey undertaken by the postman’s son Armand Roulin (played by Booth) – part memorial and part investigation into the mysterious circumstances of Van Gogh’s death in the small country town of Auvers in July 1890. Many of the characters who pop up along the way are well-known from Van Gogh’s paintings – Dr Paul Gachet and his daughter Margeurite, postman Joseph Roulin, the innkeeper Adeline Ravoux, the Girl in White and La Mousmé.

Facebook Twitter Pinterest Key scene … Saoirse Ronan as Marguerite Gachet

“Whenever a new character is introduced into the film, they are found in the position in which Van Gogh painted their portrait,” says Oliver, who is now working on Wes Anderson’s new film Isle of Dogs. “But then what you discover is that Van Gogh didn’t always paint everything at once from the same point of view. So we have Marguerite Gachet (Ronan) sitting at the piano when we first see her. But he started the painting sitting down, then at some point stood up. So we had to line a camera up to meet two, if not three viewpoints, so we could see the top of the piano, and the keyboard, and look up at her from below. Finding a photographic frame to match that expressionistic painterly frame was very interesting.”

Perspective wasn’t the only tricky element thrown up by trying to film like an expressionist. There were also the nuts-and-bolts matters of filming for animation. In one particularly beautiful scene – a black-and-white flashback sequence – we watch Van Gogh wash his face, in reflection, as if filmed from his own eyes. “I practised that bit on my girlfriend,” says Oliver. “I got a washing up bowl full of water, put it on the floor of her flat and got her to crouch over it. I had two issues; how was I going to light his face and where was I going to put the camera so you don’t see it? She complained that you should never make a woman look at her reflection when she’s facing down. But by the time I got to shooting it I knew what I was going to do.”

Facebook Twitter Pinterest Meticulously rendered … Loving Vincent

While the colour shots took their lead from Van Gogh’s paintings, the black and white sequences were, explains Oliver, influenced by a small number of photographs taken at the turn of the century. “We had one of Dr Gachet’s house, so in the scene where Vincent comes to the house and finds Saoirse sitting at the table, I did my level best to reproduce that photograph. We used a huge amount of diffusion to give that flushed-out highlight that you have from the photographic process at that time.”

Perhaps the greatest difference between painting and film-making is that, while the former is innately individual, the latter is a team effort. Not that this put Kobiela off. “Originally I planned to paint the whole film,” she says. “But the only shot I managed to paint myself was the black and white one when the boys are throwing stones at Vincent.” Having originated the idea as a short film, was it hard – once it was decided to expand it to feature length – to give over her baby to a team of collaborators? “When you’re working as a short film-maker you have complete control over every single thing you do, every movement, every frame,” she says. “It’s a Polish animation tradition that you write, direct, animate and film it yourself. So to change that way of working is very strange. But it’s also very exciting to work with that big crew of painters, actors, artists.”

Facebook Twitter Pinterest ‘Every frame was a painting on canvas. No tracing, no nothing’

What would Van Gogh make of this Technicolor portrait of his last days on Earth, I wonder. Would he approve of film-making? If he’d been alive today, would he have been drawn to the medium himself? “I imagine he would have made completely unwatchable experimental films,” says Oliver. “He was a painter. In many ways, his sheer popularity takes us away from the proper looking at his paintings – he’s too much of an icon, somehow. But, if you can really look at them again, many of them are absolutely astonishing.” Perhaps it takes a film to make us look again at paintings.

• Loving Vincent is out on 13 October.

•This article was amended on 14 October 2017 to correct the title of Wes Anderson’s new film.