Tim Dinsdale's Loch Ness Film, Foyers Bay (1960)

Tim Dinsdale was a British aeronautical engineer. An article in Everybody's magazine, "The Day I Saw the Loch Ness Monster", set him on the hunt. In April 1960 he came to Loch Ness for a six-day watch. Alone. On day four, 21 April, he saw "a churning ring of rough water, centring about what appeared to be two long black shadows, or shapes, rising and falling in the water!"

23 April 1960. The last day. About 9 a.m. From a lay-by high above Foyers, Dinsdale spotted a shape on the water across the bay, some 1300 yards away. He raised his 7× binoculars.

"The object was perfectly clear and now quite large. Although when I had first seen it, it lay sideways on, during the few seconds I had taken with the binoculars it seemed to have turned away from me. It lay motionless on the water, a long oval shape, a distinct mahogany colour. On the left flank a huge dark blotch could be seen, like the dapple on a cow."

Then it moved, and he filmed it on 16 mm cine film. The hump swam away across the loch in a glassy zigzag wake, slowly sinking lower. Then it turned abruptly left and ran parallel to the far shore, throwing up a long V wash with rhythmic bursts of foam. There was no sign of a propeller wash. The swim lasted about four minutes, with about a minute of it on film.

Dinsdale then had a 14-foot wooden fishing boat run a similar course, and filmed that too. On 13 June 1960 the Daily Mail ran the story with pictures, and the BBC showed the film on Panorama.

In 1966 the RAF's Joint Air Reconnaissance Intelligence Centre, JARIC, analysed the footage. It put the speed at about 10 mph, "the sensibly LOWEST speed from these observations." Its verdict: the object was "probably animate."

Doubts followed. In the late 1990s Richard Carter argued it was an angler's boat with a Seagull 5 hp outboard. JARIC, he said, had missed the gaps where the camera was rewound, which inflated the speed. In 2003 Adrian Shine stacked more than 100 frames and found "a pale blob towards the rear end", where a helmsman would sit. Dick Raynor also argued for a boat. Steve Plambeck described "a helmsman near the stern and a probable second person amidships."

Critics noted that the comparison boat was white and filmed in different light. A 1993 enhancement for the Discovery Channel's Loch Ness Discovered claimed to show the body of a large animal beneath the surface. Sceptics put that down to reflections of the shore. Most researchers do not believe Dinsdale was a hoaxer, though some fault his confirmation bias. Darren Naish wrote in 2019 that the film "almost certainly doesn't depict a monster", while Dinsdale's son Simon, a retired Essex police detective, insists it is genuine.

The film helped spur the founding of the Loch Ness Phenomena Investigation Bureau in March 1962, by Peter Scott, Richard Fitter, David James and Constance Whyte. Dinsdale led field groups for the Bureau and wrote five books, beginning with Loch Ness Monster in 1961. He died in 1987. His son Angus Dinsdale told his story in The Man Who Filmed Nessie. In 2023 BBC Scotland returned to the film in Loch Ness: They Created a Monster.