The Loch Ness Flipper Photographs (Rines, Urquhart Bay, 1972)

Robert H. Rines was a patent lawyer and inventor, and president of the Academy of Applied Science. He had a personal reason to be at Loch Ness. At the hillside home of Wing Commander Basil Cary and his wife Winifred, above Urquhart Bay, Rines and his wife Carol watched a hump cross the water. Sources date it to 23 June 1971 or 1972. Basil Cary put it simply: "My dear. That couldn't be an upturned boat." Rines described "a large, darkish hump, covered ... with rough, mottled skin, like the back of an elephant."

August 1972. The Academy, working with the Loch Ness Phenomenon Investigation Bureau, set up in Urquhart Bay near Temple Pier. Two boats sat about 36 m apart. The Narwhal carried a Raytheon DC 725 sonar. Beneath the Nan hung a 16 mm time-lapse camera and a 50 W strobe, the work of Harold "Doc" Edgerton of MIT. Every 45 seconds or so, the camera fired into the dark water.

Around 1:45 a.m., the Narwhal's skipper, Peter Davies, saw a trace appear on the sonar chart. He rowed over to the Nan to tell Rines and the others. The team read the marks as large animals with "dorsal humps and large projections on the body." The moving targets were estimated at 6 to 9 metres (20 to 30 ft) long.

Around 2,000 frames were exposed. Two seemed to show a diamond-shaped "rhomboid flipper or fin against a rough body." The team put the flipper at four to six feet long, in good agreement, they said, with the sonar. A third frame held two separate, hazy images.

At NASA's Jet Propulsion Laboratory, Alan Gillespie computer-processed the frames. His results were messy, coarse-grained masses without sharp edges. Then, in October, Rines circulated a clean-edged version. It was released on 1 November 1972, including in Time magazine.

In 1975 Peter Scott and Rines went further. Writing in Nature, they named the animal Nessiteras rhombopteryx, "Ness wonder with a diamond fin," and argued it deserved conservation protection. Politician Nicholas Fairbairn noticed the letters rearranged into "Monster hoax by Sir Peter S." A coincidence. Scott believed.

In January 1976, in Nature, Gordon Corbet of the British Museum called the work "sloppy, unsatisfactory." In 1984, Discover and the Skeptical Inquirer reported that the flippers had been painted over. Engineers Rikki Razdan and Alan Kielar had obtained Gillespie's copies and found them vague and indistinct. Charles W. Wyckoff acknowledged that "the original enhancement showed a considerably less-distinct object." In 2001 Adrian Shine showed that the clean edges had been added by paintbrush. Gillespie said they had "nothing to do with him."

Sceptics favour a humbler answer. The camera may have been looking at mud on the loch floor, marked by the rig itself. Others suggest bubbles, sediment, rocks or ordinary fish fins. Darren Naish of TetZoo blamed "wishful thinking and over-keen desperation," not deliberate fraud.

Rines kept searching for decades, returning in 1975 and still hunting in 2008 on roughly his 20th trip. Roy Mackal wondered about a giant embolomere, and Steuart Campbell and others weighed the evidence in print. Yet no modern software has conjured a flipper from the original frames. The 1972 photographs endure as a classic lesson in image processing, and as a portrait of wishful thinking at the loch.