Eventually photographs began to appear from 1972 onwards and earned Frank a degree of fame as a monster hunter.
However, as the detail of the pictures increasingly improved with time, people began to suspect they were fakes.
The matter was finally exposed in 1976 when the Scottish Sunday Mail carried a centre-page article proving that one of his photographs was taken from a postcard showing an Apatosaurus.
As his reputation declined, he was involved with some skirmishes with other monster researchers which eventually led to a failed molotov cocktail attack on one of their boats.
Eventually he left the loch for good in the early 1980s to allegedly embark on a treasure hunting expedition.