Sir David Attenborough has revealed he was a rebel who was "sneered at" by the BBC film department at the beginning of his career as some of his early natural history programmes are to be shown in colour for the first time to mark his 90th birthday.
The 1950s series Zoo Quest originally aired in black and white, but when footage was unearthed by the BBC Natural History Unit last year it was found to have been shot in colour.
Modern audiences will now have the chance to see the footage alongside interviews with Sir David that reveal that his plan of how to film the series was at first viewed as "amateur" by the BBC.
In the programme Sir David said Zoo Quest may never have been made because the film department initially vetoed his planned use of a lightweight 16mm film camera, rather than a larger 35mm camera, as "beneath contempt".
Sir David said: "We were rebels really and rather sneered at by the film department."
Zoo Quest was shown over a period of 10 years from 1954 with Sir David and cameraman Charles Lagus travelling to to places including West Africa, Guiana and Indonesia in search of creatures to take back to London Zoo.
The film department eventually relented when Sir David and Mr Lagus agreed to use 16mm colour film, which would allow better quality pictures, for black and white broadcasting.
The lighter camera allowed Mr Lagus the mobility to more easily capture shots of animals, people and places that viewing audiences had never seen before.
Sir David was just 28 and Mr Lagus was 26 when they began filming the series which launched both of their careers.
Mr Lagus went on to become a renowned wildlife cameraman and Sir David the world's most famous naturalist and natural history presenter. He turned 90 on May 8.
Sir David said: "They were good days and I wouldn't change them... Looking back I don't think you would let two kids in their 20s just go off like that and nobody asked us anything about health and safety or anything else. I mean we just disappeared and they said, when will you be back? Oh just before Christmas, I think. Oh right-o, goodbye. So happy days."
The pair faced real danger when the series included the first ever filming of Komodo Dragons in colour, on a remote island in Indonesia.
The duo almost never made it there when the boat that they were travelling in hit a major tropical storm and nearly got sucked into a whirlpool.
Mr Lagus said: "Quite honestly neither of us were sure that we would ever see each other again... it was that dicey."
David Attenborough's Zoo Quest in Colour will be shown on Tuesday May 17 at 9pm on BBC Four.