dismissed the loch ness monster as a mythical creature, for its many believers and wannabe believers, the question remains. what is she?. tim dinsdale devoted his life to answering this question. >> he first went up in april 1960, and every year thereafter he went to find loch ness every year thereafter, he went to loch ness. from the end of 1960s, he'd given up his work and job and was doing this full-time. >> but he never captures nessie as clearly as he did in 1960. there have been other photos and films, but the dinsdale footage remains iconic. >> i often say witnesses seldom lie. cameras very often do. sometimes without their owner's knowledge. the dinsdale film of 1960, it's quite a poor quality film, which makes identification difficult. >> my father's film, to this day, stands as being unexplained. but i think -- i'm convinced --