Sixty years ago, in a factory in Kowloon Bay, a product came into being that would revolutionise photography - not that anyone thought so at the time: the Diana was a cheap plastic toy camera that didn't work very well and was designed to be more or less disposable. Yet it has become a classic precisely because of its deficiencies. The Diana was really basic: made entirely from plastic, including the lens, its faults were manifold. The housing didn't fit properly and usually had to be taped to prevent light leakage - light randomly splashing across the images. The view through the viewfinder didn't necessarily represent the content of the photo. The film needed to be wound on manually, but it wasn't clear how far you should wind it, so the number of 4cm by 4cm photos on a roll of film was unpredictable, and there was the ever-present possibility of a double exposure if you forgot the winding bit; also, the film didn't fit very well and often jammed. [The camera's appeal lies in] the unexpected distortion of images. It's like I'm shooting reality, but it is not the same as what I see and understand. It means that seeing is not believing. Tony Lim, Hong Kong photographer The camera had three aperture settings and variable focus, but the shutter was set at a single speed - or at least it was in theory, but in practice it could vary unpredictably from about 1/100 of a second to about 1/50. Users loved it partly because it was lightweight, but that also meant it tended to wobble when shooting. Although it was made in Hong Kong by the Great Wall Plastics Factory, the Diana was for export: it was most popular in Britain and especially the US - the distance scale was given in feet - where they retailed for an eye-poppingly cheap US$1, and sometimes even less. They were sold wholesale for about a quarter of that, and as a result were often given away free as prizes and promotional items, frequently branded with the names of the companies giving them away; Reader's Digest is particularly ubiquitous. The camera's unreliability, however, meant that when better-quality, low-price cameras came along the Diana's days were numbered, and production ceased in the mid-1970s. It seemed, like so much redundant technology, destined for the great landfill of history, except for one factor: the unpredictable, glitchy effects it produces are sought by aficionados of the art of lomography, or lo-fi photography, which respositions its technological defects as advantages. Diana images are soft-focus, unpredictably blurry and full of unexpected light effects, with a dreamy, colour-saturated quality. No two images are the same; in fact, no two cameras are the same - no two Dianas will record the same scene in the same way. Hong Kong photographer Tony Lim Chi-kin, who has more than 80 Dianas, which he has collected since 2003, says the camera's appeal lies in "the unexpected distortion of images. It's like I'm shooting reality, but it is not the same as what I see and understand. It means that seeing is not believing." Sanami Kwok Tung, Hong Kong-based Asia regional online manager of the Lomography company, says: "It's the very dreamy effect created by the plastic lens - the photos have character. There's also the fact that you can add lots of accessories, plus the look is really classic - some people just like to have it in their homes, and you often see the Diana as a prop in photo shoots in fashion magazines. It's a very good camera to learn about film photography, and it's a really interesting tool to create art projects." The term "lomography" refers both to the artistic movement and, with an upper-case "L", to the organisation that promotes it, Austrian company Lomographische AG, which sells updated versions of vintage cameras and promotes the culture of lo-fi photography with its Lomographic Society. Lomography started in Austria in 1991 as an art movement, when a group of art students found they liked the imperfect images created by the Lomo Kompakt Automat camera made by the Lomo company of St Petersburg in the then Soviet Union. The emphasis is on spontaneity, and on focusing on the subject rather than the camera - lomographers point and shoot rather than worrying about setting the camera up or trying to get some kind of mythical best image. Photos are displayed in exhibitions as panel-mounted galleries of images, forming impressionistic collages. With a playful tone that betrays its origins as a contemporary art project, the organisation positions lomography less as a simple photographic proposition and more as a lifestyle, a way of looking at the world, and even has 10 Golden Rules - the last being to not worry about rules. In a world where almost everyone carries a professional-quality digital camera in their smartphone, the idea of imperfect, uncontrollable photography has a certain appeal. Lomography has shops around the world, including one in Sheung Wan, which has a film developing lab. The company sells Lomo cameras outside Russia, along with other vintage cameras - including an updated version of the Diana called the Diana F+, which Kwok says "has been one of our bestsellers for a long time". It's pretty similar to the original, although gussied up with pinhole and panorama functions; it's more solidly made and so not as unpredictable. A flavour of the mildly geeky but cheeringly community-oriented nature of Diana ownership comes in the small hardback book given free to all Diana F+ buyers. The Diana F+ is made in China but the original Diana 151 and Diana F, the latter with a built-in flash, were "Made in Hong Kong". The company that created it, which like the camera itself started life in 1955, is still in business today, albeit with a different name and focus: Great Wall (Optical) Plastic Works, now part of Cosmos Machinery Enterprises and located in Cheung Sha Wan, with a factory in Dongguan, makes binoculars, microscopes and magnifying glasses under the brand names Lumagny and Waltex. A spokeswoman says no one who worked on the Diana remains there today. So successful was Great Wall's first signature product - and so lax intellectual property laws - that numerous copycat cameras sprung up under more than 100 names, including some made in Macau; the best known is probably the Hong Kong-made Debonair. The Sinomax clone was also made in Hong Kong for a British import-export business, Sino Trading Company, owned by Denis Rattle, who used a photo on one side of the packaging of his infant son Simon - now Sir Simon Rattle, principal conductor of the Berlin Philharmonic and the future music director of the London Symphony Orchestra. Among other cheap cameras produced in Hong Kong, the Holga has achieved equally revered status among lovers of lo-fi photography, but it wasn't produced until 1981. "I think that the Diana and the Holga produce fairly similar pictures, but the Diana is way more beautiful," says Michael Kuhle, a noted Diana photographer who used to work for the Lomographic Society. "The case is lighter and the colours are fantastic. It looks like a great piece of old-school design." Perhaps the best-known Diana collector, though, has been American photographer Allan Detrich, who had the world's biggest collection of nearly 200 Dianas and its clones before it was bought by Lomography in 2007. The company introduced the Diana F+ the same year, followed by the Diana Mini, a quaint miniaturised version dwarfed by its own outsized flashbulb that comes clothed in a variety of funky housings. The company has collaborated with artists on designs for Dianas; there's even a limited edition red, white and black version, Meg, produced in collaboration with Detroit garage rock band The White Stripes. The Diana F+ sells for HK$698 and the Diana Mini for HK$788 (there's also the Diana Deluxe Kit, costing HK$1,980, and featuring a big box of goodies, including various lenses, viewfinders and adapters). Most original vintage Dianas and their clones, meanwhile, go for anything from about HK$200 to about HK$800 on the secondary market - the clones are cheaper - but rare models can run to two or three times that. From US$1 to US$300: it's just another stage in one of the most unpredictable journeys a cheap consumer product has ever undergone.