Panasonic shows compact camera with interchangable lens

The Lumix DMC-G1 has interchangeable lenses, a feature usually only found on SLR cameras, but Panasonic has done away with the bulky mirror and prism used in SLR viewfinders, so light comes through the DMC-G1’s lens and straight to an image sensor. The result is a camera that is much smaller and lighter than an SLR while still retaining some—but not all—of the benefits those models have.
Panasonic unveiled the camera on Friday in Tokyo and will show it at next week’s Photokina show in Germany. It will be available in Japan, Europe and North America in October and will cost around ¥80,000 (US$747), €800 (US$1,120) and $800, respectively. It’s aimed at casual users who want to take better pictures than is possible with a compact camera but don’t want a bulky SLR.

Panasonic’s Lumix DMC-G1 digital still camera (Photo by Martyn Williams, IDG News Service)
Compact cameras have separate lenses for the viewfinder and image sensor, which means that what you see in the viewfinder is not necessarily what you capture. Single-lense reflex cameras, as their name suggests, use a single lens for the viewfinder and image sensor, with a retractable mirror behind the lens to reflect the light up towards a prism and into the viewfinder so the user can compose the shot. When the shutter button is pressed the mirror momentarily moves out of the way, allowing the light to hit the image sensor or film at the back of the camera, recording the image.
This arrangement necessitates the use of the viewfinder and doesn’t allow users to frame their shots with the display on the back of the camera. That’s sometimes an inconvenience, especially for those used to compact cameras. In the last few years manufacturers have developed ways to get the so-called “live preview” on the LCD, for example by adding a second image sensor, but that hasn’t made the cameras any smaller.
Panasonic has done away with this mirror arrangement altogether. Right behind the lens is a 12.1-megapixel image sensor that provides both a live preview and captures the image. Shots can be composed using the LCD on the rear or through a viewfinder that’s actually a small, high-resolution LCD panel.
Because the LCD is showing a live view of what’s coming through the lens it’s possible to adjust various settings such as the shutter speed and see what effect they will have on the finished picture before taking a photo.
But there are some disadvantages. In tests of sample cameras at the launch news conference the live preview was shut down for about four seconds after each photo was taken. Not only are digital SLR cameras much faster in handling images but because you’re looking directly through the lens you never lose sight of your subject.
Thanks to this simpler design the DMC-G1 measures 124 millimeters by 84mm by 45mm, and weighs just 385 grams. That’s a little over double the weight of the compact 14-megapixel Lumix FX150 but lighter than digital SLRs such as Nikon’s recently announced D90, which weighs 620 grams.
The camera is the first to use the new Micro Four Thirds System lens mount. It’s a smaller version of the Four Thirds System developed by Olympus and the new version was designed to allow just such compact cameras with interchangeable lenses.
Panasonic announced standard and telephoto zoom lenses based on Micro Four Thirds। The standard lens is a 14-45mm model (35mm camera equivalent: 28-90mm) and the telephoto is 45-200mm (35mm equivalent: 90-400mm). Four Thirds System lenses can also be used with the new camera with an adapter.
Reference : http://www.macworld.com/article/135520/2008/09/lumixdmcg1.html?lsrc=rss_main