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The Sony α7, α7R and α7S are three closely related digital cameras. The first two were announced on 16 October 2013〔(Sony announces α7 and α7R: first full-frame mirrorless cameras: Digital Photography Review ). Dpreview.com. Retrieved on 2013-10-30.〕 and the third on 6 April 2014. Externally they are identical except for the model number. They are Sony’s first full-frame mirrorless interchangeable lens cameras and share the E-mount with the company’s smaller sensor NEX series. The α7 II was announced in November 2014, and is the first in the family to revise the original body and ergonomics. The α7 series is targeted at experienced users, enthusiasts and professionals.〔(Sony Global - Sony Global - Digital Imaging - α7 ). Sony.net (2013-10-16). Retrieved on 2013-10-30.〕 The α7R II was announced in June 2015. The Sony α7 and α7R have the model numbers ILCE-7 and ILCE-7R respectively. In addition, the α7S, the α7 II, and the α7R II have the model numbers ILCE-7S, ILCE-7M2, and ILCE-7RM2. Sony's new model naming prefix strives to unify model names. "ILC" indicates Interchangeable Lens Camera followed by an indicator of A-mount "A" or E-mount "E" Pre-announcement rumours speculated that the new camera would be named "Sony NEX-9". Although the α7 series uses full-frame sensors and have a DSLR-shaped design, their sizes and weights are less than Olympus OM-D E-M1 with its small micro four thirds sensor and can also be compared with the lightest full-frame DSLR.〔(【引用サイトリンク】title=2013 High-End Mirrorless Camera Comparison Guide )〕 Compared to the smallest and lightest APS-C DSLR Canon EOS 100D, the α7 is 67 grams heavier and a bit larger, but the thickness is only two thirds of Canon's.〔(【引用サイトリンク】title=Canon EOS 100D / Rebel SL1 specifications )〕 The α7 price is significantly lower than a comparative full-frame DSLR price, but still higher than that of a low or mid-end compact camera price.〔(【引用サイトリンク】title=Mirrorless cameras offer glimmer of hope to makers )〕 Compared to the Nikon D800E, the weight of Sony α7R is only about a half and the price is about two-thirds.〔(【引用サイトリンク】title=Sony Alpha α7R verdict )〕 ==Variations == There are six different models available in the α7 series. They are the α7 (ILCE-7), α7R (ILCE-7R), α7S (ILCE-7S) as well as the α7 II (ILCE-7M2), α7R II (ILCE-7RM2) and α7S II (ILCE-7SM2). The basic α7 model has 24 MP and hybrid autofocus. The "R" model is the 36 MP "resolution" version of the series with a new, higher-density sensor design, and priced $600 more than the α7 at launch, but has no optical low-pass filter as the sibling has. However, the α7R does not include the faster hybrid auto-focus system found on the base model. The "S" model is a high sensitivity version of the series with an effective ISO range from 100 to 409600 and with 4K video capability, but only 12 MP. The α7 II model uses the same sensor (with minor tweaks) as the original α7, but significantly revises the external ergonomics and adds image stabilization as the world's first five-axis sensor-shift image stabilisation system for a full-frame ILC. Sony claimed that this can compensate a 4.5-stop equivalent of camera shake. In-body stabilization requires no special lens features, and mirrorless system cameras can typically accommodate lenses from any SLR system.〔(【引用サイトリンク】title=Sony α7 II Review )〕〔(【引用サイトリンク】title=The New Sony α7 Mark II )〕 As an upgrade of the α7, the α7 II has the same 50 Mbit XAVC-S codec as the α7S but lacks 4K video, and the five-axis stabilisation is less effective in video mode than that used in the Olympus OM-D E-M1.〔(【引用サイトリンク】 title=Sony α7 II review – 5 axis stabilisation in video mode )〕 However, the crop mode used in the α7 II does not incur "very much loss in image quality", unlike that of the Nikon D750.〔 On 2015-06-14, Hasselblad announced the Lusso, a variant of the Sony α7R marketed by Hasselblad. 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「Sony A7」の詳細全文を読む スポンサード リンク
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