Beatles fans always knew John Lennon as "the one with the glasses".

But this rare picture shows Paul McCartney wearing a pair of thick horn-rimmed specs while deep in discussion with the band about their classic album Sgt Pepper's Lonely Hearts Club Band.

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With a little help from my lens: Ringo, left, Paul, George Martin, John and George at Abbey Road Studios in 1967

The previously unpublished photograph is one of a rare set taken as The Beatles worked at Abbey Road studios in North London.

Friends of the singer say McCartney rarely wore glasses because it was part of his friend John's image.

"He was always conscious that John was famous for his glasses," said one friend. "He felt that it was important to maintain their image and John's glasses were part of that.

"His eyesight is also pretty good, so he didn't need to wear them much."

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Few other photographs of McCartney wearing glasses exist. He wore them occasionally in public during the Sixties, and on the front cover of a Beatles fan magazine in 1964 but has not been photographed wearing them since. A spokesman for McCartney last night said he did not wear contact lenses, nor wore glasses in private.

The image is one of 40 taken by celebrated photographer Frank Herrmann on March 30, 1967, and features in an exclusive spread in The Mail on Sunday's Live magazine today.

Photographers were rarely granted access to the Fab Four in the studio and the negatives from this session were later lost.

Our pictures have been painstakingly recreated from contact sheets kept by Mr Herrmann, who said: "It was obvious they weren't comfortable with me around. Abbey Road was considered a private sanctuary."