Sony Alpha 900

From Wikipedia, the free encyclopedia
Jump to navigation Jump to search
Sony α 900
Alpha 900.jpg
Type Single-lens reflex
Lens Sony mount; compatible with Minolta A-type bayonet mount.
Sensor 35.9 mm × 24.0 mm Exmor CMOS sensor
Maximum resolution 24.6 megapixels
ASA/ISO range ISO 100–6400

Memory Stick: Memory Stick Duo, Memory Stick PRO Duo, Memory Stick PRO-HG Duo

Compact Flash Type I, Type II (Microdrive), UDMA (Mode5) compliant
Focus modes Wide AF area, Spot AF area (center), Focus area selection (any of 9)
Focus areas TTL CCD line sensors (9-points, center dual cross types + 10 assist sensors)
Exposure modes Mode: Auto, Program Auto (P, with program shift), Aperture priority (A), Shutter priority (S), Manual (M)
Exposure metering

TTL metering Cell: 40-segment honeycomb-pattern SPC Range: 0 EV to 20 EV (+2 EV to +20 EV with Spot metering)

(at ISO 100 equivalent with F1.4 lens)
Metering modes Multi segment, Spot, Centre weighted
Shutter Electronically controlled, vertical-traverse, focal-plane type
Shutter speed range 1/8000 sec. – 30 sec., bulb
Continuous shooting 5fps
Viewfinder Fixed eye-level system with optical glass type pentaprism, approximately 100%, 0.74x Magnification
Rear LCD monitor 3.0", 921,600 dots
Battery NP-FM500H Lithium-Ion rechargeable battery (1650 mAh)
Optional battery packs Vertical Grip VG-C90AM
Weight 850 g (30 oz)
Made in Japan

The α900 (DSLR-A900) is a full-frame digital SLR camera, produced by Sony. An early design study of the camera was shown at PMA on 8 March 2007, and a newer prototype announced at PMA 2008 on 31 January 2008. Sony officially introduced the final camera on 9 September 2008 prior to photokina 2008. In October 2011, Sony Japan announced the camera's end of production.

The specifications include: 24.6-megapixel CMOS sensor, 5 frame/s burst mode, dual BIONZ processors, 100% viewfinder, 9-point AF with 10 assist points, inbuilt image sensor shift stabilization and intelligent preview. It does not have video/movie recording.

Intelligent preview mode[edit]

This mode, first introduced on the DSLR-A900, allows the photographer to take a sample image at the current settings. When this mode is enabled in the settings (default), then using the depth of field (DOF) preview button makes a preview image of the subject. The display shows the image and its image histogram, but it is not stored on the memory card. At that point, the photographer can accept current settings or simulate how the image (and histogram) would look with changes in aperture, shutter speed, dynamic range optimizer and white balance. If the photographer prefers those new settings he simply continues to work to accept them. Otherwise he can reject them by depressing the garbage can icon. He can also compare the sample to the simulation by depressing the DISP button.

Predecessor to the DSLR-A850[edit]

The DSLR-A900 requires a labour-intensive alignment procedure in the factory in order to provide a 100% scene view in the viewfinder. In eliminating this costly procedure by masking the view to a slightly smaller area (98%) while also downspecifying the frame rate to 3 frames per second, the DSLR-A850 offers a camera with most of the benefits of the DSLR-A900 at a significant saving to the photographer.

External links[edit]