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In a flash - How to go digital without buying a new camera

点击量:   时间:2017-12-24 02:01:11

By Ben Crystall YOUR camera will soon be able to take digital pictures as well as photographs on film. A Californian electronics company has just announced a compact unit that can turn any 35-millimetre camera into a digital camera. Until now, digital images could only be produced with a dedicated digital camera or by scanning ordinary photographs. But the new unit, developed by the Imagek division of Irvine Sensors of Costa Mesa, fits into the back of any 35-millimetre camera, says the company’s vice-president, Bruce Totty. Most digital cameras use light-sensitive charge-coupled device chips to record an image. The chips produce an electronic signal that is proportional to the amount of light striking them. Imagek’s cartridge uses a different technology, based on complementary metal oxide semiconductors. CMOS circuitry allows more components to be squeezed onto a single chip and uses less power than conventional electronics. But until last year, says Totty, CMOS was too expensive for many applications. In the unit, the CMOS sensor is mounted on a plate, which is attached to a cartridge that is roughly the size of a standard film (see Diagram). “The cartridge contains batteries, electronics and the storage device,” says Totty. Dropping the unit into the camera places the sensor in the focal plane of the lens, where the film would normally be. When the shutter is opened, the sensor records an image, which is then stored on the 40 megabytes of flash memory chips tucked away inside the cartridge. This is enough to store 30 high-resolution images, in 24-bit colour, each made up of 1.3 million pixels. Opening the shutter automatically triggers the sensor, says Totty. To view or print the images, or transfer them to a disc, you plug the unit’s connectors into one of the ports on the back of a computer. When the unit is full, the pictures have to be downloaded before it can be re-used. John Henshall, a fellow of the British Institute of Photographers, says that there may be problems with the technology, such as some types of camera failing to recock for the next shot. “But I believe the problems are all surmountable,