OP Home > Gear > Cameras > The New Breed Of DSLRs


Tuesday, January 31, 2012

The New Breed Of DSLRs

Canon, Nikon, Sigma and Sony are pushing into new territory with their latest high-end camera models

Labels: Gear
This Article Features Photo Zoom
Sony SLT-A77
At the end of summer 2011, Sony introduced several new cameras, including the advanced A77. This pro-grade DSLR provides continuous phase-detection autofocusing even during live-view and video shooting, thanks to its unique translucent-mirror system. In conventional DSLRs, the SLR mirror rests in the "down" position for composing and focusing, then flips up out of the light path during exposure so light can reach the image sensor. A major drawback is that the phase-detection AF system can't function when the mirror is in the "up" position because light can't reach the AF sensor. The mirror must be up for live-view (and video) to function, so phase-detection AF usually isn't possible in these modes.

With Sony's SLT technology, the mirror is translucent and fixed in the down position. It reflects a small portion of the light coming through the lens up to the phase-detection AF sensor, while transmitting most of the light to the image sensor. Thus, the phase-detection AF system can function at all times, even for live-view and video shooting.

Full-time phase-detection AF isn't the A77's only major asset. The 24.3-megapixel APS-C image sensor delivers 6000x4000-pixel images in RAW or JPEG form. A new Bionz imaging engine can process all that data quickly enough to permit shooting full-resolution images (RAW or JPEG) at 12 fps with continuous autofocus (albeit with the lens at its widest aperture and exposure locked at the first frame). It also can shoot at 8 fps at any aperture, with exposure set for each frame.

Instead of an SLR's pentaprism or pentamirror optical viewfinder, the A77 has an OLED Tru-Finder. This remarkable XGA (2.4-million-dot) eye-level electronic viewfinder performs better than previous EVFs. In fact, we were able to track birds in flight with it with our preproduction test camera. The finder shows 100% of the actual image area, at a 1.09x magnification (with a 50mm lens at infinity), and provides dioptric eyepiece correction from -4.0 to +3.0, which is more than typical DSLR finders. It also can show extensive shooting information, if desired, as well as previewing exposure compensation, white balance and Creative Style settings. You can display three types of grids, which are especially helpful for keeping the horizon horizontal in landscapes.

Auto HDR quickly shoots three bracketed exposures and merges the best of each into an image with detail from shadows through highlights—even for handheld shooting. Dynamic Range Optimizer improves shadow and highlight detail with a single shot. Handheld Twilight shoots a six-shot burst at different settings, then uses proprietary Sony digital compositing technology and noise reduction to produce a single image with suppressed blur and noise. A built-in GPS unit automatically geotags your images as you shoot (with latitude, longitude and altitude). The camera uses that data to determine where a specific image was shot. Sweep Panorama makes it easy to create dramatic stitched panorama images in-camera simply by sweeping the camera across a scene. There's even a 3D Sweep Panorama mode.

The A77 is well sealed against moisture and dust, and the rugged magnesium-alloy body has a shutter tested to 150,000 cycles, and there's a sensor-dust removal system. The DT 16-50mm ƒ/2.8 SSM kit zoom, VG-C77AM vertical grip and HVL-F43AM flash unit also are sealed against weather and dust. The camera automatically corrects for vignetting, chromatic aberration and distortion, and offers AF fine-tuning.

The camera has a new AVCHD Progressive 2.0 codec, which provides 1920x1080 full HD video at 60p, 60i and 24p for a cinematic look. The A77 also can shoot 1440x1080 and 640x480 MP4 video at 30p. And you get eye-level viewing and full-time phase-detection AF while shooting. The camera has a 3.0-inch, 921,000-dot LCD monitor that tilts 150° up and 180° down, as well as 180° clockwise and 90° counterclockwise. You can record stereo sound via built-in microphones, and plug an external microphone into the provided jack.

Like all Sony DSLRs, the A77 has the Sony SteadyShot INSIDE sensor-shift image stabilization. Because this stabilization system is in the body, it's compatible with all lenses.

The A77 can use all Sony A-mount lenses and legacy Konica Minolta Maxxum lenses. The Sony lineup currently numbers 30, from an 11-18mm superwide zoom to a 70-400mm zoom, including a 16mm fisheye and three macro lenses, plus 1.4x and 2x teleconverters.


Add Comment


Popular OP Articles