Sir Paul McCartney called the guitarist, who died in 2001, "a great man" and "an all-round good boy".

Scorsese told the BBC he had been drawn to tell Harrison's story because of the outlook of his lyrics.

"For years, his music seemed to be dealing with themes that I connected with," he said.

"I found comfort in them and a hope and a special experience listening to his music. I was fascinated by him."

The Oscar-winning director said Harrison's love of India had changed western culture.

"George was the one to open our minds to this, that this could be of value to you in your life, to you and everyone you love. His music really expresses that." 

The documentary, George Harrison: Living In The Material World, will receive a limited cinematic release, before being shown on the BBC in the UK and on HBO in the US.

It is split into two parts - first chronicling the Beatles' rise to fame, then documenting the solo years, when Harrison juggled music with philanthropic work and a career as a movie impresario.

Five years in the making, the three-and-a-half hour film was pieced together as Scorsese worked on Shutter Island and forthcoming 3D family film Hugo.

He said it had been made possible by Harrison's widow, Olivia, who threw open the family archive of photos, home videos and personal effects.

At one point in the film, Dhani Harrison is heard reading from his father's diary: "January 10 - got up, went to Twickenham, rehearsed until lunchtime, left The Beatles."

Olivia Harrison told the BBC it had been "hard to part with" elements of the archive, "but they finally convinced me it was ok".

Fond memories

The London premiere was partnered with a charity screening in Harrison's hometown of Liverpool.  

Viewers there said the film "brought to life how there were four people in the Beatles".

"You hear so much about Lennon and McCartney, but without George and Ringo, they wouldn't have been there," one fan told the BBC.

In London, the premiere was attended by the Beatles' former producer Sir George Martin, Yoko Ono, Noel Gallagher, Sir Ben Kingsley, Billy Connolly, Terry Gilliam, Ronnie Wood and Harrison's former wife, Pattie Boyd.

Sir Paul, who was accompanied by his fiancee Nancy Shevell, said watching the film had been an emotional experience.

"Every time I see something to do with George it brings back more memories than you would believe. He was my little mate on the school bus. A lot of fond memories. He's sorely missed by us all."

Ringo Starr said it was moving that films were still being made about the guitarist, 10 years after his death.

"It's far out. It's far out. It's like the Beatles go on forever."

George Harrison: Living In The Material World will be available on DVD and Blu-Ray from 10th October, and will be shown as an Arena Special on BBC Two later this year. 

 http://www.bbc.co.uk/news/entertainment-arts-15147935