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The Micro Four Thirds system (MFT) is a standard created by Olympus and Panasonic, and announced on August 5, 2008, for the design and development of mirrorless interchangeable lens digital cameras, camcorders and lenses. In 2014, JK Imaging Ltd., which holds the Kodak brand, released its first Micro Four Thirds camera, the Kodak Pixpro S-1; several lenses and niche camera makers have products made for the standard. In 2015, a drone company provides its drone with optional Micro Four Thirds cameras. Both cameras can captures 16MP stills and up to 4K/30fps video with optional of 4 interchangeable lenses ranging from 12mm to 17mm.〔(【引用サイトリンク】title=DJI unveils custom aerial Micro Four Thirds camera )〕 MFT shares the original image sensor size and specification with the Four Thirds system, designed for DSLRs. Unlike Four Thirds, the MFT system design specification does not provide space for a mirror box and a pentaprism, which facilitates smaller body designs and a shorter flange focal distance, and hence smaller lenses. Virtually any lens can be used on MFT camera bodies, as long as an adapter exists. For instance, Four Third lenses can be used with auto focus using the adapters designed by Olympus and Panasonic. == Sensor size and aspect ratio == The image sensor of Four Thirds and MFT is commonly referred to as a ''4/3" type'' or ''4/3 type'' sensor (inch-based sizing system is derived from now obsolete video camera tubes). The sensor measures 18 mm × 13.5 mm (22.5 mm diagonal), with an imaging area of 17.3 mm × 13.0 mm (21.6 mm diagonal), comparable to the frame size of 110 film.〔(【引用サイトリンク】title=No more compromises: The Four Thirds Standard )〕 Its area, ca. 220 mm², is approximately 30% less than the quasi-APS-C sensors used in other manufacturers' DSLRs, yet is around 9 times larger than the 1/2.5" sensors typically used in compact digital cameras. The Four Thirds system uses a 4:3 image aspect ratio, in common with other compact digital cameras but unlike quasi-APS-C or 24×36 mm DSLRs, which usually adhere to the 3:2 aspect ratio of the traditional 35 mm format. Thus the "Four Thirds" refers to both the size of the image and the aspect ratio of the sensor. Note that actual size of the chip is considerably less than 4/3 of an inch, the length of the diagonal being only 22.5 mm. The 4/3 inch designation for this size of sensor dates back to the 1950s and vidicon tubes, when the external diameter of the camera tube was measured, not the active area. The MFT design standard also calls for being able to record multiple formats, 4:3, 3:2 (traditional DSLR formats with origins with 35 mm film still cameras), 16:9 (the native HD video format specification), and 1:1 (a square format). With the exception of two MFT cameras, all MFT cameras record in a native 4:3 format image aspect ratio, and through cropping of the 4:3 image, can record in 16:9, 3:2 and 1:1 formats. This multiple recording format flexibility is a MFT system design standard, which also incorporates seamless integration of HD video recording in the same camera body. The 2009 introduction of the Panasonic Lumix DMC-GH1 camera extends the 4:3 format image aspect ratio recording capabilities to native 16:9 and 3:2 image aspect ratio formats, rather than crops of a native 4:3 image. The GH1 uses a bigger sensor matrix that uses the full diagonal of the image circle in all three formats. This is called multi-aspect capability. To date, the multi-aspect sensor is common only to the Panasonic GH1〔(【引用サイトリンク】Panasonic Lumix DMC-GH1 Review )〕 and its successor the Panasonic Lumix DMC-GH2.〔(【引用サイトリンク】title=Panasonic DMC-GH2 Review )〕 In addition, all current Micro Four Thirds cameras have sensor dust removal technologies, but this is not exclusive to the format. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Micro Four Thirds system」の詳細全文を読む スポンサード リンク
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