Sony Alpha DSLR-A900

Product Highlights

  • 24.6 Megapixel
  • Full-Frame (24x36mm) CMOS Sensor
  • Dust & Weather-Resistant
  • In-Camera Image Stabilization
  • 3.0″ 921,600-Pixel LCD Display
  • ISO 100-6400
  • 5.0 fps Burst
  • 100% Coverage, 0.74x Viewfinder


Sony’s Alpha DSLR-A900 SLR Digital Camera (Body Only), their first “full frame” model, has alerted the industry and consumers in the DSLR world that they’re in the digital SLR camera business for the long haul.

The DSLR-A900 starts with a 24 x 35.9mm size CMOS sensor developed especially for this camera.  Though that imaging canvas is utterly packed with pixels, the pixels themselves dominate the landscape of the image receiving area, instead of the elements of image sensors which are necessary but not actually collecting the image.  Indeed, the A900’s pixels are larger than the fine consumer-grade Alpha 700, despite having twice as many pixels.

On the physical side of things, the Alpha’s designed for professional use:  all operations are weather-sealed, its high-performance shutter’s tested to 100,000 cycles, and its viewfinder (the forgotten critical SLR element in the age of squinty APS-C size viewfinder dominance) is as good as they come.  Despite these claims, together with batteries and a memory card it tips the scales at ~2 lbs (900g), a good competitive number especially considering the enjoyable view.

Beyond physical elements, the DSLR-A900’s got plenty of brains. To speed up throughput for pro sports and action use, Sony’s employed dual “Bionz” image processors. Its two analog-to-digital engines swallow large chunks of information, shoving up to ~5 frames per second into a fast memory card-quite bold capacity considering those big RAW files.

With its image quality, handling ease, robust construction, and brilliant viewfinder, the DSLR-A900 should prove a serious tool for professionals and advanced consumers. The benefits of ‘full frame’ are plentiful; better dynamic range, more natural skin rendition, a cushy viewing experience and superior capacity to blur backgrounds. Super wide angle zooms start at focal lengths more befitting professional instruments, and are awash upon the secondhand market.

35mm-Style “Full Frame” 24.6MP Exmor CMOS Sensor

The 35.9 x 24mm 35mm-size “Exmor” CMOS image sensor is ~2.35x larger than typical APS-C size sensors, and the large capture area affords more sharpness, tonal graduation, and depth of field control. Best of all, pixels themselves dominate the square footage.

World-Class Viewfinder

Glass pentaprism optical viewfinder with 100% coverage, 0.74x magnification, and 20mm eye relief. Low magnification makes the composition canvas small, distant, and unengaging. High magnification makes a viewfinder’s eye relief impossibly short for eyeglass users. Getting both right gives an ideal conduit between ideas and images. Though tough to have long eye relief and full coverage without obnoxiously large glass atop an SLR, Sony’s succeeded here. Beyond the numbers, the brightness, size, and viewing comfort of this viewfinder returns to the forefront the primary element of camera/user interaction. There’s also a built-in shutter blind and integrated -3 to +1 dioptric correction, and bringing it to the eye disengages the LCD screen.

Professional Construction

Weather, dust, and impact sealing befits a professional SLR, and the DSLR-A900’s carbon fiber shutter is high-specification; tested for a min. 100,000 cycles, its 1/8000th second top speed and flash sync with any flash at 1/250th second (1/200th with stabilizer activated) display its manufacturing strength.

Full Frame “SteadyShot INSIDE” Stabilization

Alpha 900’s in-camera stabilization redefines common belief; a steadying effect of ~4 shutter speed steps, but with a full frame. Previous in-camera stabilizing corrected movements of ~15x22mm image receiving areas within 24 x 36mm ‘full frame’ confines, as full frame in-camera correction was believed to result in wider, taller, and thicker housings. At 6.1 x 4.6 x 3.2″ (156 x 117 x 82mm), it isn’t too big a camera-a little thick, but within professional DSLR standards. The stabilizer works with every mounted lens, instead of being an expensive and occasional component within lenses. As with all stabilizers, they don’t speed shutters-only more light, higher ISOs, or larger apertures can do that. Stabilizers benefit typical low light pics as well as handling monster telephoto lenses.

Dual Image Processing Engines

Side-by-side “BIONZ” processors yield fast 5-frames-per-second performance despite A900’s enormous files

Speedy, Intelligent AF

Precision 19-point autofocus system with 9 supremely-sensitive horizontal/vertical points, 10 outer assist points, and customized AF microadjustment for up to 30 lenses

Great 3″ LCD Monitor

3.0″ 921,600-Pixel LCD monitor has stunning detail and 270 pixels-per-inch resolving power like fine photo prints

Intelligent Preview Function

Alpha 900’s “Intelligent Preview” allows seeing effects of changing ISO, shutter speed, aperture, dynamic range optimizer and white balance settings before capturing an image, eliminating trial-and-error

HDMI Output

Direct HDMI output to BRAVIA and other HDTV-compatible screens and projectors, with “PhotoTV HD”-capable BRAVIA sets benefitting from automatically optimized display settings

Fantastic Lens Family

Sony’s Alpha lens lineup includes Carl Zeiss specialties and “G”-series flagships with in-lens silent focusing motors


Body type
Body type Mid-size SLR
Max resolution 6048 x 4032
Other resolutions 4400 x 2936, 4400 x 2936, 3024 x 2016, 6048 x 3408, 4400 x 2472, 3024 x 1704, 3924 x 2656, 2896 x 1928, 1984 x 1320
Image ratio w:h 3:2, 16:9
Effective pixels 25 megapixels
Sensor photo detectors 26 megapixels
Sensor size Full frame (35.9 x 24 mm)
Sensor type CMOS
Processor Bionz
ISO Auto, 100, 200, 400, 800, 1600, (up to 6400)
Boosted ISO (maximum) 6400
White balance presets 7
Custom white balance Yes (1)
Image stabilization Sensor-shift
Uncompressed format RAW
JPEG quality levels Extra Fine, Fine, Standard
Optics & Focus
  • Phase Detect
  • Multi-area
  • Center
  • Selective single-point
  • Single
  • Continuous
Digital zoom No
Manual focus Yes
Number of focus points 9
Lens mount Sony/Minolta Alpha
Screen / viewfinder
Articulated LCD Fixed
Screen size 3
Screen dots 921,600
Touch screen No
Screen type TFT Xtra Fine color LCD
Live view No
Viewfinder type Optical (pentaprism)
Viewfinder coverage 100%
Viewfinder magnification 0.74×
Photography features
Minimum shutter speed 30 sec
Maximum shutter speed 1/8000 sec
Aperture priority Yes
Shutter priority Yes
Manual exposure mode Yes
Subject / scene modes No
Built-in flash No
External flash Yes (Hot-shoe, Wireless plus Sync connector)
Flash modes Auto, On, Off, Red-Eye, Slow Sync, Rear Curtain, Fill-in, Wireless
Continuous drive 5.0 fps
Self-timer Yes (2 or 10 sec)
Metering modes
  • Multi
  • Center-weighted
  • Spot
Exposure compensation ±3 (at 1/3 EV steps)
AE Bracketing ±2 (3, 5 frames at 1/3 EV, 1/2 EV, 2/3 EV, 1 EV steps)
WB Bracketing No
Videography features
Microphone None
Storage types Compact Flash (Type I or II), Memory Stick Duo / Pro Duo, UDMA Mode 5, Supports FAT12 / FAT16 / FAT32
Storage included None
USB USB 2.0 (480 Mbit/sec)
HDMI Yes (mini HDMI Type C)
Remote control Yes (Wired or Wireless (Optional))
Environmentally sealed Yes (Water and Dust resistant)
Battery Battery Pack
Battery description Lithium-Ion NP-FM500H rechargeable battery & charger
Battery Life (CIPA) 880
Weight (inc. batteries) 895 g (1.97 lb / 31.57 oz)
Dimensions 156 x 117 x 82 mm (6.14 x 4.61 x 3.23)
Other features
Orientation sensor Yes
Timelapse recording No
GPS None