Sony Unveils a7S II Mirrorless Wide Dynamic Range Camera
Sony Electronics unveiled Friday the α7S II mirrorless compact system camera, offering the ability to record full-frame 4K video internally with full-pixel readout, no pixel binning and up to 14 stops of dynamic range.
The new camera also offers a range of professional movie functions including what the company calls a “unique balance of sensitivity and control of plane of focus.”
Mark Weir, Sony Electronics senior technology manager, said the a7S II is the third model in Sony’s second generation of a7 cameras, and is optimized for maximum sensitivity, particularly in low-light conditions, making it ideal for professional wedding photographers who encounter challenging low-light situations. It joins the α7 II and α7R II.
The a7S II also provides 5-axis image stabilization that further enables taking high-quality images from low-light conditions and telephoto shots.
More on the Sony a7S II after the jump:
The α7S II, which will be available through authorized Sony dealers in October at a $3,000 estimated selling price, features a 35mm-equivalent full-frame 12.2-megapixel image sensor and BIONZ X image processing engine, which combine to produce a huge 50-409600 ISO range.
Sony said the sensor works to optimize the dynamic range across the entire ISO range, “broadening the amount of tonal gradation in bright environments and minimizing noise in dark scenes.”
The BIONZ X processor includes an upgraded image processing algorithm that maximizes the sensor’s capabilities overall, in particular at the mid-high end of the ISO scale, to produce what Sony calls “extremely detailed still images and movies with minimal noise.”
The Sony a7S II captures 4K video at 24/30p internally using the XAVC S codec, which can record at bit rates up to 100 Mbps. Sony said that “because information from all pixels is utilized without line skipping or pixel binning, the camera can maximize the expanded power of the full-frame image sensor and produce 4K movies with higher image clarity and negligible moiré.”
The same capability is employed for Full HD video (24p/30p), enabling the camera to collect information using five times as many pixels as required for a 1920x1080p image. Information is then oversampled to produce movies in high detail, Sony said.
The a7S II is also Sony’s first a7 camera to record Full HD at up to 120fps at 100Mbps in full frame format. The images can be immediately reviewed on the camera screen and eventually edited into high quality 4x/5x slow motion footage in Full HD (24p/30p) resolution, the company said.
For external recording the camera will output signals with 4:2:2 chroma subsampling over HDMI, Weir said.
Video functionality has been further enhanced with new picture profile settings; S-Gamut3.Cine/S-Log3 and S-Gamut3/S-Log3, delivering wide dynamic range and simple color correction. Sony said the α7S II produces “up to 14-stops latitude in the S-Log3 gamma setting, while also supporting other popular profiles for cinematographers including S-Gamut/S-Log2.”
Sony also added a new Gamma Display Assist function that allows monitoring images or checking focus when recording S-Log movies, and improves the Zebra function for greater control.
The camera’s 5-axis image stabilization system, which is also used in the α7 II and α7R II cameras, corrects camera shake along five axes during shooting, including angular shake (pitch and yaw) which is especially problematic when capturing images using long telephoto lenses. Shift shake (X and Y axes) adjustment improves problems that arise from increased magnification, and correction for rotational shake (roll) is effective for night shooting and/or video recording.
The camera’s autofocus (AF) system was also upgraded to now offer 169 AF points for fast, precise focusing with greater accuracy compared to the original model, Sony said. The system uses contrast detection only, unlike the hybrid contrast detect/phase detect system found in other a7 II models.
The lower image noise enabled by the image sensor assists the A7S II’s Fast Intelligent AF in detecting contrast more easily in order to react more quickly in low-light situations (as low as EV-4). This level is said to be too dark to check focus with the naked eye. Sony said the a7S II’s AF performance is twice as fast as the preceding model during video shooting.
The camera is also equipped with an upgraded XGA OLED Tru-Finder to offer what Sony calls “the highest viewfinder magnification of 0.78x (roughly 38.5 degrees in diagonal field of view) and shows clear images across the entire display area.” Sony uses Zeiss T* coating to reduce reflections in the viewfinder. The OLED Tru-Finder can be used to instantly show how exposure compensation, white balance and other selected settings are affecting the displayed image.
The camera body is made from magnesium-alloy for lighter weight and durability, and the grip and shutter buttons were re-designed for more natural in-hand feel.
Silent shooting mode can be activated at up to 5 fps continuous shooting with reduced-vibration shutter movement, Sony said.
Sony said it has further reinforced the lens mount for greater rigidity, particularly when attaching third party lenses. The camera battery can also be charged via a USB power supply while the camera is in operation, Sony said.
The α7S II also includes built-in Wi-Fi connectivity with NFC and compatibility with Sony’s PlayMemories Mobile application for Android and iOS mobile devices.
The α7S II is compatible with Sony’s 64 α-mount lenses, including 13 native ‘FE’ full frame lenses. Sony said it plans to add 7 new FE lenses to the mix by early 2016.
By Greg Tarr
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