The Sony Alpha a7S Mirrorless Digital Camera features a full-frame 12.2MP Exmor CMOS sensor and BIONZ X image processor to enable notable video and still image quality with an expansive dynamic range, low noise, and extended sensitivity to ISO 409600. At the sensor level, this full-frame sensor features a unique on-chip gapless lens design, which incorporates small lenses between neighboring pixels in order to increase light-gathering efficiency and promote greater image quality across the entirety of the sensor plane. The sensor and processor combination also avails a wealth of speed throughout the camera system, including a top continuous shooting rate of 5 fps, support for 4K video recording, and a fast 25-point contrast-detection AF system with sensitivity to -4 EV.
Beyond its still image performance, the a7S is also quite adept in regard to recording video. It is able to output uncompressed 4:2:2 UHD 4K video to an optional external recorder over HDMI, as well as record full HD 1080p video in the high-quality XAVC S format at 50 Mbps in multiple frame rates. Extending the video recording capabilities is support for S-Log2 gamma, which helps to expand the effective dynamic range during recording, as well as picture profile options, time code, and zebra marker display aids. Sound can be recorded in the AAC/Linear PCM format via the internal stereo microphone, with a built-in headphone jack for on-board monitoring, or via an external microphone.
Rounding out the a7S's imaging capabilities, both a 3.0" 921.6k-dot tilting LCD monitor and 2.36 million-dot OLED electronic viewfinder are available for image monitoring and review. Built-in Wi-Fi connectivity, with support for NFC, is available, too, for instant sharing of imagery from the camera as well as remote camera control from a linked mobile device.
The sensor's design also features a new-generation RGB color filter array, as well as a gapless on-chip lens design. Together, these two technologies enable truly efficient light-gathering abilities that further reinforce the low noise, high-sensitivity design. Furthermore, an anti-reflective coating has also been applied to the seal glass of the image sensor to minimize surface reflections, glare, and ghosting for contrast-rich, color-neutral imagery.
The sensor and processor combination also avail a wealth of performance-related benefits to still shooting, including a Speed Priority continuous shooting rate of 5 fps, or a 2.5 fps shooting rate with continuous AF. The contrast-detection AF system employs 25 distinct points to quickly and precisely acquire focus in light levels as low as -4 EV to support working in a wide variety of shooting conditions.
For times when the high quality 50 Mbps XAVC S Codec is not enough the a7S is able to output uncompressed UHD 4K (3840 x 2160) at a 4:2:2 color depth over HDMI to compatible third party recorders. Or, if recording internally to a memory card the HDMI can output 1080p at 4:2:2 for external recorders or HD monitors that don't support 4K inputs. The full list of supported HDMI output signals is:
- 3840 x 2160 (30p/24p)
- 1920 x 1080 (60p/24p)
- 1920 x 1080 (60i), YCbCr 4:2:2 8-bit/RGB 8-bit
For monitoring audio the a7S features a 3.5mm headphone jack as well as real time audio levels for a visual reference.
Additionally, PlayMemories Camera Apps are also supported via the built-in Wi-Fi connection, and allow you to personalize the camera's features depending on specific shooting styles. Apps are available to suit creating portraits, detailed close-ups, sports, time lapse, motion shot, and other specific types of imagery.
- Picture Effect modes: Posterization (Color, B&W), Pop Color, Retro Photo, Partial Color (R/G/B/Y), High Contrast Monochrome, Toy Camera, Soft High-Key, Soft Focus, HDR Painting, Rich-Tone Monochrome, Miniature, Watercolor, and Illustration.
- Create Style settings: Standard, Vivid, Neutral, Clear, Deep, Light, Portrait, Landscape, Sunset, Night Scene, Autumn Leaves, Black & White, and Sepia (all with +/- 3 step contrast, saturation, and sharpness adjustment).
- Color space: sRGB standard (with sYCC gamut) and Adobe RGB standard compatible with TRILUMINOS Color.
- Picture Profile parameters: Black Level, Gamma (Movie, Still, Cine 1-4, ITU709, ITU709 [800%], S-Log2), Black Gamma, Knee, Color Mode, Color Level, Color Phase, Color Depth, Detail, Copy, and Reset.
- Scene Selection modes: Portrait, Landscape, Macro, Sports Action, Sunset, Night Portrait, Night Scene, Hand-held Twilight, and Anti Motion Blur.
- Face Detection is available to base exposure and focus on up to eight recognized faces. Furthermore, Eye AF can be used for even greater precision by maintaining critical focus on a subject's eye.
- Auto Object Framing automatically creates compositions revolving around portrait and still life subjects and aesthetically crops imagery based on the rule of thirds, where the subject is located within the frame, exposure on your subject, and, in the case of portraiture, the direction he or she is looking.
- 2x Clear Image Zoom can be used to effectively double the magnification afforded by any lens in use with minimal image degradation. For even greater magnification, 1.5x and 2x Smart zoom is available, as well as 4x digital zoom.
- Playback modes: Single (with or without shooting information, Y RGB histogram & highlight/shadow warning), 9/25-frame index view, Enlarged display mode (Maximum magnification L: 13.3x, M: 8.7x, S: 6.7x), Auto Review (10/5/2 sec., off), Image orientation (Auto/Manual/Off selectable), Slideshow, Panorama scrolling, Folder selection (Still/Date/MP4/AVCHD/XAVC S), Forward/Rewind (Movie), Delete, and Protect.