Sony's latest interchangeable lens cameras, the SLT Alpha A33 and A55 represent a significant technological milestone - not just for Sony but for the enthusiast camera market as a whole.
The company has rejected the traditional DSLR design and instead created a hybrid that, like a compact camera, is from the ground up built around live view, but one that is also capable of offering full-time DSLR-style phase-detection autofocus. The combination means they can offer features such as phase-detection AF during movie recording and extremely fast continuous shooting rates (10 frames per second on the A55), previously unthinkable at this price.
This is made possible by adopting an approach that has more in common with a mirrorless camera (like the Panasonic G2, for example) than an SLR by removing the bits that pretty much define such cameras: the optical viewfinder and moving mirror.
The designation 'SLT' stands for single lens translucent and it's the 'translucent' bit that's the key to what differentiates these new models both from conventional DSLRs and mirrorless interchangeable lens cameras. The SLTs do have mirrors, but they're mirrors that let the majority of the light pass straight through to the sensor, rather than having to swing out of the way to allow exposure. As a result they are fixed in position, always reflecting a portion of the light emerging from the back of the lens onto a phase-detection AF array housed in the top of the camera. (A newly-developed 15-point array in the case of these two cameras).
Spesifikasi Sony SLT Alpha A55
Price (with 18-55 mm kit lens) | • US: $749 • EU: €850 |
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Body material | Plastic |
Sensor | • APS-C "Exmor" HD CMOS • 16.7 million total pixels • 16.2 million effective pixels • RGB (Primary) color filter array |
Image sizes | • 4912 x 3264 (3:2) • 3568 x 2368 (3:2) • 2448 x 1624 (3:2) • 4912 x 2760 (16:9) • 3568 x 2000 (16:9) • 2448 x 1376 (16:9) |
Image sizes (Video) | • AVCHD: • 1920 x 1080, 59.94i (from 29.97fps sensor output) • MP4: • 1440 x 1080, 29.97p or 25p, depending on region • 640 x 480, 29.94 fps |
Aspect ratios | • 3:2 • 16:9 • variable (Sweep Panorama) |
File formats | • RAW • RAW + JPEG • RAW + JPEG Fine • JPEG (EXIF 2.2) - Standard • JPEG (EXIF 2.2) - Fine |
File formats (Movie) | • AVCHD Ver. 1.0 compliant Video: MPEG-4 AVC/H.264 • MPEG-4 AVC/H.264 |
Lenses | • Sony A-mount • Konica-Minolta AF mount |
Focus modes | • Auto Focus (15-point phase-detection AF system) • Manual focus • Face Detection • AF Tracking |
AF assist lamp | Yes, dedicated lamp |
Image stabilization | Super SteadyShot INSIDE |
Extended optical zoom | N/A |
Digital zoom | N/A |
Exposure modes | • Program AE • Aperture priority AE • Shutter priority AE • Manual • Auto • Auto + • High-speed mode (10-fps) • Sweep Panorama (2D/3D) • SCN (see below) • Flash off |
Scene modes | • Portrait • Sports Action • Macro • Landscape • Sunset • Night view • Hand held Twilight • Night portrait |
Scene modes (movie) | • Portrait • Sports Action • Macro • Landscape • Sunset • Night view • Hand held Twilight • Night portrait |
Sensitivity | • Auto • Intelligent ISO • ISO 100 • ISO 200 • ISO 400 • ISO 800 • ISO 1600 • ISO 3200 • ISO 6400 • ISO 12800 • ISO 25600 (multi-shot NR mode - JPEG only) |
ISO steps | 1/3 or 1.0 EV |
Metering range | -2 to 17 EV |
Metering modes | • 1200-zone multi-segment • Center-Weighted • Spot |
AE Lock | • AEL/AFL button • With shutter release half-press |
AE Bracketing | • 3 frames • in 1/3 or 2/3 |
Exposure compensation | • -2 to +2 EV • 1/3 EV steps |
Shutter speed | • 60 -1/4000 sec. • Bulb • Flash X-sync 1/160 sec |
White balance | • Auto • Daylight • Shade • Cloudy • Incandescent • Fluorescent • Flash • Kelvin temp (2500 - 9900K, 100K steps) |
WB fine tuning | Yes (magenta/green bias) |
WB Bracketing | N/A |
Color space | • sRGB • Adobe RGB |
Image parameters | • Creative Style (Standard, Vivid, Portrait, Landscape, Sunset, B/W) • Saturation (5 levels) • Contrast (5 levels) • Saturation (5 levels) • Sharpness (5 levels) |
Drive modes | • Single • Continuous Hi (6 fps) • Continuous Lo (3 fps) • 10 fps via high-speed mode |
Continuous buffer | • 35 JPEG Fine images • 39 JPEG Std images • 20 RAW images • 20 RAW+JPEG images |
Self-timer | • 2 sec • 10 sec |
Flash | • Manual pop-up • TTL auto / manual • Guide no. 10 (ISO 100) • Sync modes: Auto, Fill flash, Slow sync, Rear-curtain sync, Red-eye reduction on/off, Wireless • Flash exposure compensation: Up to +/- 2EV in 1/3 EV steps |
Flash X-sync speed | 1/160 sec |
External flash | • Hot shoe |
Viewfinder | • Electronic Viewfinder • Color LCD Viewfinder • Field of view 100% • Eye point 19mm • Magnification 1.1x • Dioptre adjustment -4 to +4 dioptre • 1,440,000 dots (of which 1,152,000 are used) • Field Sequential (RGB) |
DOF preview | Yes |
Orientation sensor | Yes |
LCD monitor | • 3.0" TFT LCD monitor • Multi-angle swing and tilt (180°swing, 180° swivel)* • Low temperature Polycrystalline TFT LCD • 921,600 dots • Approx 100% frame coverage • Auto / Manual (5 steps between -2 and +2) / Sunny Weather |
Playback functions | • Single (with or without shooting information • RGB histogram & highlight/shadow warning) • 6/12-frame index view • Enlarged display mode (L: 11.8x, M: 8.8x, S: 6x) • Image orientation (On/Off selectable) • Slideshow • Panorama scrolling • Auto Review (10/5/2 sec Off selectable) • Folder selectable (still image) • Slow-forward (movie) • fast-forward/fast-rewind (movie) |
Connectivity | • USB 2.0 (High Speed) • HDMI type C |
Print compliance | • Exif Print • Print Image Matching III • DPOF setting |
Storage | SD/SDHC/SDXC/MemoryStick Pro Duo |
Power | • NP-FW50 Lithium-Ion rechargeable battery • Supplied charger / AC adapter (sold separately) |
Dimensions | 124 x 92 x 85 mm (4.8 x 3.6 x 3.3 in) |
Weight (camera body) | Approx. 441g (0.97lb) |
Weight (camera body, card and battery) | Approx. 500g (1.1lb) |