New film Mrs Lowry & Son explores the complex relationship between the acclaimed artist LS Lowry and his mother, who disapproved of his work. Laura Harding sits down with star Timothy Spall to learn how he prepared to play another artist, after JMW Turner, and what he learned about the life of the great Manchester painter.

The painter LS Lowry has long been lauded as one of Britain's most important artists but there was one person who did not see his potential - his mother.

The new film Mrs Lowry & Son explores the complex relationship between the pair, who lived together until her death in 1939.

It follows Lowry, played by Timothy Spall, at the beginning of his career as he hungers for his work to be appreciated by critics and galleries. Meanwhile his mother Elizabeth (Vanessa Redgrave) actively dissuades her son from pursuing his ambitions.

"I knew zero about this relationship," Spall freely admits. "I didn't know anything, that is why I was so intrigued by the script when I read it.

"I thought it was a remarkable tale and when I read it, it almost instantly started to make sense - the paintings started to make sense - and I could see all of a sudden where they all come from."

"The work is is far, far deeper and far more profound than I realised and, I think, than a lot of people give it credit for."

Lowry is renowned around the world for his depictions of industrial life in England's North West in the 20th century, using a distinctive style of painting for works abundant with human figures often referred to as "matchstick men".

Much of his output is now housed in The Lowry, a purpose-built gallery in Salford Quays, which played a key part in Spall's research.

"I spent a lot of time just starting at the paintings. I went on a very quiet day the first time and I was just able to just stare at them and watch the films they have around there.

"Then I bought a couple of biographies and read those and then looked at the paintings again and started to wrap my head around the man and the work and how they connected."

It became clear that Elizabeth played a vital role in Lowry's life, even though she often made it clear what a disappointment her son was to her and how ashamed she was of his work, which she regarded as grubby and ugly.

But what became evident to Spall was that she was actually the very reason her son painted anything at all, in his desperate bid to make her happy.

"I started out thinking this was, on the face of it, a very unpleasant abuse of power. But whilst in the process of doing it and thinking about it more and more I figured there was a mutual dependence.

"He had become used to that constant calling upon his time. He had been brought up to be enthralled to her every requirement and to be her carer.

"He had become used to her discontent, always desirous of her happiness, but used to being a bit of a disappointment.

"He finds it deeply frustrating that she doesn't get what he is painting and he does it for her but he always said that, in the end, 'she didn't understand my paintings but she understood me and that was enough'."

For 62-year-old Spall, who is best known for roles in the Harry Potter films, as well as The Damned United and Sweeney Todd and TV series including The Syndicate and The Street, it offered him the chance to explore another artist after his star turn as JMW Turner in 2014's Mr Turner.

"They were very, very different," he says. "They were different men of different times and different training.

"Turner was a born artist, he was encouraged almost from his birth by his father.

"Turner was immensely successful from an early age, and from 14 he was allowed access to the Royal Academy and was learning, learning, learning, whereas it was more difficult for Lowry to do that. He had to make a concerted effort.

"I don't think his parents expected him to be a professional artist. He was expected to become a man of commerce - his mother would have liked him to be a man of the community, to command some kind of respect.

"I don't think his mother would have objected as long as he painted nice things and he only did it every now and again but she tried to decry it and make it seem like a hobby, which he found deeply offensive, because it wasn't. He trained for 14 years on and off and he devoted his life to it.

"What they (Lowry and Turner) did share was the fact they didn't paint en plein air (outdoors).

"They came back to their studio having sketched. They assimilated what they saw and then painted in their studios.

"So there was similarity is their personalities, their feelings - and their emotional understanding of what they saw is transferred through the privacy of their studio into their work.

"For Lowry, he could not help but paint these things around him and this sense of bleakness and beauty and a dying industrial world and the people that populated that world.

"They are composites from his mind's eye. They are not direct representations but they are a feeling, riddled with feeling about that place, and I think riddled with that tension of that relationship (with his mother) and that is what makes them deep and profound."

He pauses.

"Lowry himself said you don't need brains to be a painter, what you do have to have is feelings and I think all great artists, whatever ilk they are, what they have is their own signature, they have their own authorship and their autograph in that work.

"Although they are totally different, there is no doubting they are complete originals."

Mrs Lowry & Son is in cinemas now.