Although Sony entered the digital SLR market by acquiring Konica Minolta (in 2006), the current Alpha models have developed far past their predecessors, retaining only the A-mount and in-camera image stabilizer. Since the first Sony model, the α100, the company has been adding entirely new technology to each generation. For example, in 2010, Sony switched to making Single Lens Translucent (SLT) models, with a fixed semi-transparent mirror and an electronic (not optical) viewfinder.
The current series of eight includes both full-frame models with a 24 x 36 mm sensor and others using the smaller APS-C size 15.6 x 23.5 mm chip; the latter produces a 1.5x crop factor with any lens. All of the SLTs feature a built-in SteadyShot stabilizer and CMOS sensor. The professional 24.3-MP full-frame α99 in a weather-sealed magnesium-alloy body with GPS receiver boasts numerous high-tech functions, including prograde versatility in video and audio recording. The other Alpha cameras use the smaller sensor with resolution from 16.1 MP and up to 24.3 MP in the α65, the α77 and the newer α77 II; these three also feature a magnesium-alloy body. The SLT cameras benefit from advanced technology developed by Sony, including some unique aspects; here’s a brief overview.
All Sony Alpha cameras are equipped with an EVF for a live view of the scene, with very high resolution: 1.44 million dots (α58) or 2.36 million dots (α65, α77, α77 II and α99), for example.
The 3” tilting high-resolution Xtra Fine LCD is becoming standard, although the smaller α58 is equipped with a 2.7” screen. All provide high resolution for a very good or superb display: at 460,800 dots (α58) or 921,600-dots (α65, α77 and α77 II), for example. Since the camera’s internal mirror does not move, live view on the LCD (and EVF) never black out.
Sony offers multi-point phase-detect AF with a full range of AF modes, including very effective continuous predictive tracking for sports photography. The α77 II features 79-point AF with 15 cross-type points while the α99 boasts a unique AF-D feature with 19 focus-detection points complemented by an extra 102 points to maintain focus on a subject that drifts far off centre. This allows the α99 to provide superior continuous AF (with certain Sony lenses) when shooting fast, erratic action.
This engine (often updated for new models) provides adaptive noise-reduction technology and allows for hightech features such as Auto Object Framing (automatic JPEG cropping for better composition) and Sweep Panorama mode, many special-effect options, and multi-frame modes for amazing image quality at very high ISO levels. The processor is very fast; for example, the α77 and α77 II can shoot 24.3-MP photos at a blazing 12 fps.
DYNAMIC RANGE OPTIMIZER
All Sony cameras offer intelligent multi-zone light metering, with an option to use DRO for greater highlight and shadow detail. Multi-frame Auto HDR is also standard with Alpha cameras, for dramatically increased dynamic range.
WIRELESS OFF-CAMERA FLASH AND WI-FI
The built-in flash can trigger remote flash units (of certain models) so there’s no need for an extra-cost accessory. Wi-Fi is not standard but it is provided by the α77 II with an NFC feature and available Sony apps.
FULL HD MOVIE MODE
The current Alpha cameras can all record 1080p video with stereo sound in MP4 format, or in AVCHD for exceptional movie quality, with fast continuous phase-detect autofocus in P mode or with manual focus in A, S or M mode.
LENSES AND ACCESSORIES
Sony markets over 30 A-mount lenses for their full-frame and small sensor Alpha cameras, including many with low-dispersion and aspherical elements and/or fast, nearly silent ultrasonic (SSM) focus motor or the new Smooth Autofocus Motor (SAM). The series includes some pro-grade Zeiss models with superb construction and optics. All Alpha cameras are also compatible with the old Minolta Maxxum AF lenses.
Other accessories include cases, remote controllers, a vertical battery grip for the α99, many flash units including some with Sony’s unique Quick Shift Bounce system for use when shooting verticals, external stereo mics, an XLR adapter for the α99, an external LCD and an LED light.