But the images he has filmed since 2007 from the suburban Istanbul holiday village where he works as a night watchman have helped turn UFO-spotting, once the object of scorn, into a relatively popular pastime among some educated Turks.
"For me it's just a hobby, a way of passing the night," Mr. Yalcin shrugged recently. In mid-June over a thousand Turks paid the handsome sum of 35 lira ($22) to attend a weekend conference in Istanbul, where they listened to Yalcin and UFO-ologists from around the world discuss their latest findings.
Holding cups of watery coffee selling at an extortionate 3 lira, elegantly dressed Turkish ladies with word-perfect English peppered speakers from as far away as Mexico with questions about 2012 and the end of the Mayan calendar.
A former head of the British Defense Ministry's UFO desk and a well-known UFO-ologist, Nick Pope, one of the speakers at the conference, confessed himself amazed at the turnout. "UFO-ology has a bit of an image problem back home, computer-nerds, train-spotters, you know," he said. "But that is not the sense I get here at all. And there seems to be an equal balance between men and women."
Haktan Akdogan, the organizer of the International UFO and New Age Congress, the fourth of its kind in Turkey, attributed growing domestic interest in UFO sightings to increasingly receptive Turkish media coverage. Turkish outlets are "more sympathetic than the media in the West," Akdogan said.
He went on to describe Yalcin Yalman's films of bright crescent-shaped objects hovering over the Marmara Sea, some of them apparently with humanoid figures inside them, as "a turning point for Turkish UFO studies."
"These are the most remarkable images taken in Turkish history," he said, sitting in the central Istanbul office of the Sirius UFO Space Science Studies Centre that he set up in 1997. "Authorities can no longer turn a blind eye to this phenomenon."
Increased Turkish tolerance for reported alien sightings has spread well beyond the media. When an alien purportedly appeared in front of a farmer outside the southwestern Turkish village of Narli in 2001, the farmer responded in time-honored style: he threw rocks until the creature shot into the air "to the height of a minaret" and disappeared. Seven years later, when a UFO reportedly reappeared in the same village, it was met by cameras, not stones.
This year, however, the most striking UFO revelations have come from members of Istanbul's showbiz scene. Reyhan Karaca, a singer who represented Turkey at the Eurovision Song Contest in 1991, told Turkish newspapers this May how a "prawn-colored" alien had plucked her from her bed one night and had taken her on a whistle-stop tour of Earth. "They were very friendly," she said of the inhabitants of the spacecraft that abducted her. "We communicated using our thoughts."
A couple of days later, Hulya Avsar, a pop singer and television host who is a household name in Turkey, told Ms. Karaca and her own talk show audience, that she had seen a UFO from the balcony of her villa too.
Yalcin Yalman's images have been savaged on several UFO-ology web sites. Nick Pope describes them as "very interesting," before adding that "unless you get a proper analysis there is a risk of misinterpretation."
Generally, though, skepticism was in short supply among ticket-holders at the Istanbul UFO conference. And the intensity of their beliefs seemed to pay off. At the end of the first day, as a crowd milled outside the World of Wonders hotel, where the conference was held, a purported UFO suddenly appeared in the sky overhead. Hands went for cameras so fast that Lucky Luke would have been left standing. "I think they were showing their support for us: we're here, can you see," Haktan Akdogan told a TV channel that broadcast footage of the event a couple of days later.
Asked whether he is unnerved by UFOs' apparent predilection for materializing in front of him, Yalcin Yalman smiled and clicked his tongue, the Turkish equivalent of shaking your head. "I see them as the world's policemen, up there to keep an eye on us," he says, taking a puff on his cigarette. "I only wish they'd come down for a chat. Then we could drink tea and play a few rounds of backgammon."
Nicolas Birch specializes in Turkey, Iran and the Middle East.