Basic Specifications
Full model name: Sony Alpha SLT-A77
Resolution: 24.30 Megapixels
Sensor size: APS-C
(23.7mm x 15.6mm)
Kit Lens: 3.13x zoom
(24-75mm eq.)
Viewfinder: EVF / LCD
Native ISO: 100 - 16,000
Extended ISO: 50 - 16,000
Shutter: 1/8000 - 30 sec
Max Aperture: 2.8 (kit lens)
Dimensions: 5.6 x 4.1 x 3.2 in.
(143 x 104 x 81 mm)
Weight: 48.1 oz (1,363 g)
includes batteries, kit lens
Availability: 10/2011
Manufacturer: Sony
Full specs: Sony A77 specifications
Sony Alpha (Minolta A) APS-C
size sensor
image of Sony Alpha SLT-A77
Front side of Sony A77 digital camera Front side of Sony A77 digital camera Front side of Sony A77 digital camera Front side of Sony A77 digital camera Front side of Sony A77 digital camera

A77 Summary

Making a major leap in the camera market, the Sony A77 reaches into pro territory, able to capture 12 frames per second with a 24.3-megapixel camera that feels great and handles like your typical enthusiast digital SLR. Its optional 16-50mm kit lens also delivers excellent quality for the money.


Very fast top frame rate; full-time phase-detect autofocus; Full 60p HD video; Excellent kit lens; Very good high-resolution sensor.


Heavy; EVF appears dim when used in bright light; AF tracking in Movie mode was unreliable in our testing.

Price and availability

The Sony SLT-A77 became available in the US market from October 2011. Body-only pricing is set at approximately US$1,400, while a kit version including the Sony DT 16-50mm F2.8 SSM standard zoom lens is priced at around US$2,000. (The lens itself is also available separately, priced at around US$800.) The VG-C77AM vertical grip costs about US$300.

Imaging Resource rating

4.5 out of 5.0

Sony A77 Review

by Dave Etchells, Mike Tomkins, Zig Weidelich, and Shawn Barnett
Hands-on Preview Posted: 08/24/2011
Review Posted: 04/24/2012
Updated: 01/16/2013 (Performance page updated with v1.06 firmware and faster card)
Updated: 01/25/2013 (AF tracking tests added to Video page)

The long awaited and badly overdue successor to the A700 has finally materialized in the form of the Sony A77, an Alpha that absolutely does not disappoint. In more than one area, the new camera significantly raises the bar for the prosumer SLR, from its 24.3-megapixel APS-C sensor to its 12-frame-per-second capture rate with full-time autofocus, a speed heretofore unattainable at any price. Mated to the new 16-50mm f/2.8 constant aperture lens -- an optic that serves the 24-megapixel sensor quite well, as we'll see -- the Sony A77 represents quite a leap in imaging technology at its $2,000 price point.

The primary leap is made possible thanks to the application of several technologies into a higher-end camera, chief of which is the Translucent Mirror Technology (TMT), which combined with use of an electronic first curtain, allows the Sony A77 to capture 12 frames per second with less noise and vibration. Until Sony's introduction of TMT, the fastest frame rate while maintaining full autofocus was found in the $5,000 Canon 1D Mark IV, which is capable of 10 frames per second while maintaining autofocus tracking.

Ergonomics. Plainly put, the Sony A77 feels and looks a lot like older enthusiast-level Canon SLRs. Not a bad design to emulate. I'm not saying it's a clone, or even intentional, but as one intimately familiar with Canon SLRs, the design makes me feel right at home; there are also elements that remind me of some Nikon models. While I liked the Sony A700's decidedly machine-like feel, the A77 feels more organic, and more in-tune with the rest of the SLR market. The grip is tacky and soft, very comfortable against skin. There's a nice relief to guide the middle finger into a comfortable position, and a gentle ridge rises inside the grip to give the tips of the fingers better purchase. It's necessary when the camera is combined with the rather heavy 16-50mm lens. That's not a complaint, by the way. Heavy is good when you want stability, and this combo captures such detail it needs the heft to work against constant, subtle human motion. Its heft is due partly to the magnesium alloy molded body shells front and back, and the 16-50mm f/2.8 lens also contributes noticeably to the weight of the Sony A77.

I find the shutter button a little high (higher than I'm used to from Canon SLRs), but that makes sense considering the Front control dial's position on the front of the grip. The tacky grip material wraps around to the rear, making an excellent thumbgrip.


One of the more pleasant finds on the Sony A77 is the AF-assist lamp. It's of a design that disappeared on Canon SLRs several years ago. It throws a red light, but one with a vertical line pattern that allows the camera to focus in complete darkness. It makes me wish Canon would bring it back; then again, here it is. There's also an infrared port nestled into the grip, a Depth-of-field preview button (not visible) lower left of the lens, and the AF mode selector dial.

The 16-50mm lens is a pleasure to behold and to use. Adhering to the straight, cylindrical design of other Sony lenses, the lens looks somewhat incongruous against the A77's smooth organic shape, but the two work together very well. The stout, perfectly ridged rubber rings turn smoothly, though the action requires a little more pressure than normal. It gives a sense of solid design, with tight weather-sealing and a robust internal mechanism. Though there's a lock switch to hold the lens at 16mm, I have yet to experience any lens creep. Point the lens down all you want, it won't creep. At least ours won't.

The mode dial is plastic with a knurled rubber band around it. It's comfortable to turn, and yet doesn't turn too easily for my taste. Front and rear control dials are also rubber, and both comfortable and responsive. Between the pop-up flash and hot shoe is a curved grille that conceals the stereo microphone. The grille is designed to minimize noise from the lens focus mechanism.

The Status LCD is handy to have, something the A700 lacked. All of the buttons are either smooth domes or concavities and give with clean, clear pops when pressed. Top deck buttons essentially mirror what you'll find on older Canon SLRs, including Drive mode, White Balance, ISO and EV. Since all of these are adjusted via the Status LCD, it makes sense. The shutter button has a fairly clear half-press, followed by uncertain mush. I quickly learned when it would fire, though, without a problem.

A thick, pliant rubber arches over the viewfinder opening. It's a little thicker than I'm used to from other SLRs, yet yields nicely as I press my glasses up against it for a better view of the OLED screen inside. A sensor over the opening turns on the OLED when your eye approaches. This is true whether you have the camera's LCD/EVF switch in Auto or Manual mode.

There's a gentle upward cant on the left of the Sony A77's bottom plate for a more comfortable hold while fingers reach out to control the lens.

I really like the joystick. Its sharp edge makes it easy to direct, while not tedious for the thumb. I liked the old one better, but this one seems less likely to break over time. An inward press on the button serves to make selections. All of the other buttons seem well-placed for easy access, though more than once I found myself pressing the AEL button instead of the Movie button when trying to record a movie.

The new swiveling LCD mechanism is at first novel, then a little befuddling, but once you learn just how to set it for different shooting situations, it's fine. I won't say it's necessarily better than other solutions, but it's not bad at all. First, like the Sony A65, the LCD is hinged at the bottom, where it can articulate down 180 degrees, then swing around 270 degrees. From there, a second horizontally articulating hinge nested in the A77's back plate swings out with a detent at 90 degrees, then it tilts up further about 80 degrees. A whole host of odd positions are possible, but only a few are useful on a regular basis. The LCD itself is a 921,600-dot display that is transflective, which means it's good indoors and in sunlight.


Shooting with the Sony A77

by Shawn Barnett

Right away, I could tell something was different. We'd heard the presentation, which sounded pretty good, but it wasn't until I held the Sony A77 that I knew something had changed. I felt the same way when I used the Sony A700, the camera the A77 replaces. I won't go too much into detail about my disappointment that the A700 went so long without an upgrade or successor; suffice it to say that I thought that camera was Sony's best chance at making a dent in the Canon/Nikon hegemony, and instead of addressing its few flaws, Sony was spending too much time trying to appeal to the consumer market, a place where Nikon and Canon dominate even more pervasively. I've long thought that to be successful in this market, Sony needed to impress the enthusiast first: Give them a real reason to switch, and some of the masses would begin to follow.

That reason, of course, appeared however stealthily in two other consumer cameras, the Sony A33 and A55: the Translucent Mirror Technology that enabled a high frame rate (7 and 10 fps) and continuous phase-detect autofocus from two sub-$1,000 cameras. But I wasn't sure these would get the attention needed to make a dent, worthy as the technology was. It just didn't seem like the message would get out, and the two cameras looked so much like EVF long zooms, I didn't think anyone would take them seriously. Despite that concern, searches for this line of cameras is reasonably high. But the real difference will come with the Sony A77. Capturing 24.3 megapixels at 12 frames per second changes everything. I haven't been this excited about a camera in some time, but based on my experience with the Sony A77, I'd buy one. 

I've already outlined most of the user experience at the top of this review. To recap: The Sony A77 is comfortable to hold and use, button placement is excellent, and its relative similarity to other SLRs on the market makes me feel right at home.

Viewfinder versus LCD. Sony's fundamental translucent mirror technology means there's no optical viewfinder to use when framing your images, so Sony draws a live image off the sensor and displays it on a relatively large OLED screen inside the viewfinder. The effect is more advanced than you're used to seeing from LCD electronic viewfinders. Instead of the distracting grid of pixels that normally greet your eye, the OLED in the Sony A77 is smooth and fairly high resolution.

It's pretty good for framing images when indoors, and it even gains up nicely to help you see detail that you can't see with your eye (though the refresh rate slows a bit). But outdoors it's a different story. While we normally turn to optical viewfinders and even EVFs in bright light, I find my eye taking a little more time to adjust to the OLED EVF in the A77's viewfinder. A sensor over the viewfinder detects my eye and makes the switch between the LCD and EVF, but usually doesn't make the switch fast enough, leaving me first in the dark, then I see a screen that's a little too dark at first, then my eye adjusts. It's not a comfortable set of changes, going from very bright to very dark, then to somewhat bright, so most often I and my colleagues shied away from the EVF when out in daylight, preferring the LCD.

Shadow detail. I got much better shadow detail than the optical viewfinder suggested.

The other problem I had with the electronic viewfinder is a tendency for shadows to appear plugged in high-contrast situations like the one at right. All of the foreground shadow was quite black in the EVF, which is partly why I took this shot: I wanted to see how the sensor would handle the deep shadows. Turns out the sensor did just fine, but I had discovered another limitation of the OLED viewfinder. Because I was thinking about the shadows, I don't remember if the sky in this shot was blown, another common problem among EVFs in high-dynamic-range situations.

Play. The Sony A77's quick nature is great for getting the family at play.

The good news is that the Sony A77's articulating LCD is excellent in both bright and dim light. Its 921,600 dots make another smooth image, one that seems to be transflective, or both transmissive and reflective. Sunlight striking its surface reflects back in relatively bright color that is quite a bit better than trying to read some LCDs through a dark cover-glass. Its unique swiveling mechanism is tough to describe, but I found myself using it a lot as I shot both cars and kids, because both benefit from shooting at a lower angle. At first it seems to be hinged at the bottom like past Sony designs, but then a horizontal hinge not unlike that used on Sony's NEX cameras swings out from the back, allowing the LCD a much greater range of motion. It can even face forward from the top or bottom. The joints are hinged with enough stiffness that the LCD stays where you leave it, so it's versatile. Figuring out which way to turn it for maximum effectiveness isn't obvious at first. When shooting low and vertically, I first swiveled the the LCD down, then to the right, so that the LCD faced upward with my right hand on the grip. However, it was often very difficult to frame images, because when I moved the camera left or right, the image moved in or out. The key is to use the second hinge. Swiveling that out presses the left edge of the LCD up against the EVF's rubber cup, and the image then matches: moving the camera left moves the image left, and moving right moves the image right.

Flash. The detail in this image is astonishing.

Subjects: Kids. In terms of close subjects, nothing moves faster than kids, except maybe butterflies. While my first thought of 12 frames per second was for capturing sports, having that high speed capture rate seemed perfectly logical when trying to capture a single good shot of my toddler. She's my most elusive subject. All my other children have been easy to photograph, but this little one is always changing. So when a single press on the shutter resulted in two or three shots almost instantaneously, I could see the potential; sadly the bright sunlight resulted in many squinty images instead of what I was looking for.

Droplets are plentiful in this shot, and you can even read his watch in the bottom shot.

I managed a shot with the pop-up flash, without the high-speed on. The lens hood of course cast a shadow on her left shoulder, but it's a good shot, with ridiculous detail. (Note that our Gallery images were taken with a pre-production beta unit. See our lab shots for production-level images.)

For action, I knew I could count on my son to keep moving and let me keep trying to catch him as he ran around the Centennial Olympic Park fountain. My favorite aspect of the Sony A900 was that it felt like you had captured the world in a snapshot so you could look at it in greater detail later at your computer. That's true of these two A77 shots as well. The water is frozen in the air, and a close-up reveals hundreds of tiny droplets as he splashes through the fountain. You can even look at his watch and see what time it was. The images are both underexposed, something I ran into occasionally with the prototype unit, but I prefer that to overexposure; the image looks great with a quick Levels adjustment in Photoshop, but as usual we try to post what the camera captures unmodified.

Sports. I had good positioning at a recent high school football game, and the Sony A77 combined with the f/2.8 70-200mm G were working as I'd hoped. Unfortunately, a storm rolled in right after the first quarter, so I didn't really get warmed up before lightning strikes ended the game (an all-too-common occurrence in Southern sports). Naturally I had the camera in 12 fps mode to see what I could capture. With all the refs and other players walking in front of the camera, it's not all that easy to get the nice shots you see in Sports Illustrated, nor is it easy to see that pigskin as the light fades, as it was doing while the storm rolled in. Still, with the Sony A77 set to ISO 800, I was able to capture one good sequence as the runner successfully sheds a determined defender.

12 fps. These three shots give you an idea of how well you can pick your moment at a sporting event. Here are links to the full-res images: YDSC00857.JPG, YDSC00858.JPG, YDSC00859.JPG

Focus starts a little soft on the runner's face in the first shot, perhaps because of motion on my part, but the other two are pretty crisp. I enjoy the determined expression on the runner's face. It's good detail for ISO 800.

I also caught a field goal kick for another example of 12 fps in action, which you can see in the Gallery. When the camera goes off it sounds really cool, but doesn't draw a lot of attention thanks to the lack of a mechanical mirror and the electronic first curtain. It's a very different sound from what you've heard on other cameras, and really serves up the images. You get a very brief preview of each image as it's captured, allowing you to track the subject well enough. As I saw the action in the game interrupted by a player or person on the sidelines I was able to ease off the shutter release, shooting short bursts that allowed me to follow longer plays reasonably well. At one point I did find myself running up against the buffer by the time the player reached the end zone, so celebratory touchdown shots were unavailable. Ultimately, you only have about a second of 12 fps if you just hold that shutter down, so you do have to learn to fire in short bursts. Perhaps they could program in a 3-shot burst mode, as are available in some machine guns for better buffer allocation.

Detail. The last 24-megapixel camera I reviewed was the Sony A900, and I took it to World of Coke in Atlanta, a museum to the sugary beverage's history. It's positioned in a location that offers a great view of the Atlanta skyline, right across from the Georgia Aquarium. Sony representatives more than once said that they thought the image quality from this new sensor rivaled that of full frame, so I made the same shot -- as close as I could -- within weeks of when I made the original shot (August 13, 2011 vs. August 31, 2008). The weather is remarkably similar, even if the lighting and time of day is different (note that the dates and times stamped into the A77's files are incorrect). It's very nearly a draw. Look at the crops below and see for yourself. At times the edge goes to the full-frame Sony A900, at times to the A77. At the outer edges of the frame, the 16-50mm lens shows a little softening, which you can see in the last crop below, but it's truly remarkable performance from a lens that effectively costs $600 when purchased as a kit, while the full-frame 24-70mm Carl Zeiss lens sells for around $1,750.  See our Sony DT 16-50mm F2.8 SSM review on

Sony A77 with 16-50mm f/2.8 Sony A900 with Zeiss 24-70mm f/2.8

Panorama. Surely people thought I was nuts holding an SLR while running the motor drive in a panning motion. A few even looked to see what action I might be following, but of course I was making a panorama, something I've done with other cameras at this site, but usually in a slower, more methodical way, capturing one shot at a time. Sony's Sweep Panorama makes it easy. I took several dozen sweeps at different times that afternoon, and you can see the best in the gallery. Ultimately I chose the one I made at sunset and cropped it. To get a good panorama with any camera, its best to shoot straight at the horizon line, something made easier thanks to the level function in the viewfinder and on the LCD. At sunset, that meant I captured a huge swath of lawn, darkened by the shade from the structures behind me. But it's such a large image that I was able to crop it down to just what I wanted.

I stepped back to get the cloud in this shot, but didn't want all the shaded grass up front. But I had a plan.

Back at the computer I cropped most of the grass and sweetened the colors a bit for a nice panorama.
Click on either image for a larger look.

AF tracking. Because the main purpose of the translucent mirror is full-time autofocus, we tested it as we have with other Sony SLT cameras, with a car driving at the camera at 30 miles per hour. Where results with the prototype model were a little spotty, our production sample delivered just exceptional focus accuracy and tracking: Virtually every frame was in sharp focus, even up to 40 mph, and the car as close as about 15 feet from the camera. This is just an exceptional level of AF tracking performance, the Sony A77 should have no trouble at with typical fast-breaking sports action. Video, though, was a rather difference experience, see the Sony A77 video page for details on what we found there.


Sony A77 Technical Info

by Mike Tomkins and Dave Etchells

Sensor and processor. At the heart of the Sony SLT-A77 is an impressively high-resolution 24.3 megapixel Exmor APS HD CMOS image sensor, whose output is handled by the latest version of the company's proprietary Bionz image processing engine. Total pixel count is some 24.7 megapixels, and the sensor's dimensions are 23.5 x 15.6mm, yielding a 1.5x focal length crop when compared with 35mm lenses. The SLT-A77's sensor has a standard RGB Bayer color filter.

With a 3:2 aspect ratio, the SLT-A77 can provide maximum image dimensions of 6,000 x 4,000 pixels at full resolution. Two further 3:2 aspect ratio resolutions are available: 4,240 x 2,832 pixels, or 3,008 x 2,000 pixels. The SLT-A77 also provides a choice of three 16:9 aspect ratio shooting modes, each of which has the same pixel width as its 3:2 aspect counterpart, but with heights of 3,376, 2,400 or 1,688 pixels respectively.

The Sony SLT-A77 offers a wide sensitivity range of ISO 100 to 16,000 equivalents, and the lower end of the range can be extended to ISO 50 equivalent. By default, sensitivities between 100 and 1,600 equivalents are also available through an Auto ISO setting, and this can be adjusted to encompass a range as wide as ISO 100 to 12,800 equivalents. High ISO noise reduction cannot be disabled altogether for JPEGs, but provides three adjustable operating strengths: High, Normal, or Low. Using the Multi-frame Noise Reduction function, you can specify the ISO sensitivity manually within an expanded range of ISO 100 to 25,600 equivalents, and the camera will average multiple exposures to create a single image with reduced noise levels.

Optics. The Sony A77 retains the same Alpha lens mount and translucent mirror design seen in the previous A33, A35, and A55 models. The company currently offers a selection of 33 Alpha mount interchangeable lenses, all compatible with the A77, and the camera will also accept historic Minolta or Konica Minolta Maxxum lenses.

The defining feature of the Sony SLT-series cameras, the translucent (or pellicle) mirror, allows most light to pass through to the imaging surface beneath, while a small portion is reflected for use by the camera's phase-detect autofocus sensor. This unusual design brings three main advantages over a traditional SLR: full-time phase detection autofocusing (even during video capture), improved burst shooting performance, and a modest reduction in camera body size.

The translucent mirror design has two main drawbacks, both related to its fixed transmission / reflection ratio. It requires use of an electronic viewfinder, since only 30% of incoming light is reflected by the mirror, and so a true optical viewfinder would be unusably dim. Also, with only 70% of incoming light received by the image sensor, Sony's SLT-series cameras aren't able to offer equal sensitivity / noise performance characteristics of a traditional SLR using the same sensor and image processing.

For photographers seeking high burst speeds or the ability to use phase detection AF during video capture, this is likely a trade-off they'll be willing to make, however. Some photographers may also consider the electronic viewfinder, which provides the ability to preview not only framing, but also functions such as white balance and creative effects, to be a positive as compared to an optical viewfinder.

Stabilization. As with its predecessors, the Sony A77 includes the company's SteadyShot sensor-shift image stabilization system. The current iteration of the system is now said to be good for a 2.5 - 4.5 stop correction, and is available with any mounted lens, regardless of focal length. (Some competitors rely on in-lens stabilization, which can provide better results at longer focal lengths, but which also potentially adds to the cost and size / weight of each lens purchased.)

Lens correction. When shooting in JPEG mode, the Sony SLT-A77 includes the ability to automatically correct lens shading (vignetting), lateral chromatic aberration, and distortion in-camera, as images are captured. At release, this feature was only available for four specific lens models: the SAL1650, SAL1855, SAL55200-2, and SAL18250, although Sony has since added support for additional 16 lens models via firmware updates.

Electronic viewfinder. Long time IR readers know that we've always been a little lukewarm toward electronic viewfinders (EVFs). To date, the tonal range, clarity, brightness, resolution, and update lag/refresh rates of EVFs have generally made them poor substitutes for the tried and true optical versions.

As technology continues to advance, though, many limitations of earlier EVFs are being addressed, and the OLED (Organic Light-Emitting Diode) technology used in the "TruFinder" found in Sony's latest Alpha and NEX models makes another large step in the right direction.

There's really more to say about the A77's OLED viewfinder than would fit here in this overview, so we've put a more complete discussion on its own page. A few quick notes are clearly in order here, though, as the viewfinder is such a large part of the Sony A77 experience.

Rich Information. The Sony A77's OLED "TruFinder" makes good use of its ample area. This is the view showing the most information; you can choose from a variety of displays, including one with no overlays on the image area.

Big, Sharp, Accurate. The first thing that strikes you about the A77's viewfinder is how big it is. If you're used to shooting with normal subframe SLRs, you're in for a pleasant surprise the first time you look through the A77's EVF. It's really more a size you'd expect to see on a high-end full-frame SLR selling for thousands of dollars more. It's also incredibly sharp; the first EVF we've seen with XGA (1,024 x 768) resolution; a staggering 2.4 million RGB dots. It also shows 100% of the frame area that the camera will capture; another feature more commonly associated with very high-end professional cameras.

Other Improvements, a couple of gripes. One of our biggest EVF gripes has been poor handling of highlight detail: It's often impossible to see what's going on with sky detail if you're shooting a landscape. The A77's TruFinder has some of the best highlight handling we've seen to date, but unfortunately gets into trouble at the other end of the tonal scale, with a tendency to plug dark areas of the image badly. Also, even at maximum brightness, the TruFinder isn't nearly as bright as a sunny day, so we found that our eyes sometimes took a few moments to adapt when we first looked through it when the surroundings were very bright.

We did feel that the TruFinder's update lag and refresh rate were considerably better than we saw on last year's A33 and A55, although it's still not quite up to the zero millisecond lag provided by an optical finder.

Finally, of course there are the things no optical viewfinder can do: For one, provide a true preview of the shot you're about to capture (including white balance and exposure), and for another offer an incredibly rich information display.

Bottom line, while we still like the visual experience of looking through an optical viewfinder, the Sony A77's TruFinder addresses a number of traditional EVF issues, and brings such a host of other benefits that we'd be happy to make the optical/EVF switch with it.

As noted, the foregoing is only a brief discussion of all the pros and cons of Sony's new OLED TruFinder; check out our A77 viewfinder page for all the details.

Displays. Like the A33 and A55 before it, the Sony SLT-A77 includes an articulated TFT LCD panel, but the articulation mechanism has been completely redesigned. Previously, the tilt/swivel mechanism was mounted at the bottom of the camera, meaning that although the LCD could be turned to face forwards, it wasn't visible from in front of the camera if shooting on a tripod or with the camera placed on a convenient flat surface. For a camera aimed at consumer and enthusiast use, we'd imagine that self-portraits and group shots in which the photographer is a participant are not an uncommon use case. The SLT-A77 corrects this oversight, with a tilt-swivel mechanism that now allows viewing from in front of the camera, as long as you're not using the popup flash or or a hot-shoe mounted external strobe.

The new mechanism has two separate hinges. The first of these folds the LCD downwards, and also includes a swivel mechanism, in much the same style as in the earlier cameras. However, instead of being fixed to the camera body, this assembly is affixed to a structure that's hinged halfway up the camera body, allowing the LCD and first hinge / swivel to fold upwards, presenting the panel at the top of the camera while providing just enough clearance for the viewfinder eyepiece. While it's definitely more versatile than the earlier mechanism, it's unfortunately still blocked for shots with on-camera flash, and we do wonder about its long-term durability, given the added complexity of the articulation mechanism. Hence we'd still consider the more traditional side-mounted tilt/swivel screens found on some competitors to be slightly preferable.

As for the panel itself, the basic specifications are also unchanged, with a three-inch diagonal, and a total resolution of 307,200 pixels (921,600 dots). The design includes Sony's TruBlack anti-glare technology, which couples a reinforced glass cover plate with anti-reflective film, and a resin filling that removes the air gap beneath the cover plate, thus improving contrast and reducing glare under harsh sunlight. There's also still an automatic brightness control with five-step manual override.

As well as its built-in color LCD panel, the Sony SLT-A77 also features a small monochrome LCD info panel on its top deck, providing quick confirmation of camera setup. It's also compatible with the company's optional CLM-V55 LCD panel accessory, a five-inch, 800 x 480 pixel display that attaches via the HDMI port, and includes a detachable hood to improve daylight visibility.

Focusing. The Sony A77 features a new 19-point CCD phase detection autofocus sensor, upgraded from the 15-point sensor used in its predecessors. The new chip greatly expands the number of cross-type focus points to eleven, up from three in earlier models. The A77's autofocus system has a working range of EV -1 to 18 at ISO 100 equivalent, with an f/2.8 lens attached.

As mentioned previously, one of the main advantages of Sony's Translucent Mirror cameras -- including the A77 -- is that this sensor can be used at all times, even during video capture. (Traditional DSLRs must switch to the slower contrast detection autofocus method during live view and video capture, or must interrupt the video feed to flip mirrors for a phase detect operation. Contrast detection is also used by all compact system cameras, with the exception of Sony's own NEX-series models when using Alpha-mount lenses with the optional LA-EA2 mount adapter.)

The SLT-A77 provides single-servo and continuous-servo autofocus operation, as well as an Automatic AF mode which switches between single and continuous types as the camera deems necessary, depending upon the subject. There's also both AF tracking and predictive control, and an AF microadjustment function that allows AF to be tweaked separately for 30 different lens types. A built-in LED autofocus illuminator helps the SLT-A77 to achieve a focus lock on nearby subjects in low ambient lighting conditions. The A77 also provides the ability to start autofocus operation instantly that you bring your eye to the electronic viewfinder, potentially reducing the time taken to achieve a focus lock

As you'd expect, it's also possible to focus manually with the Sony SLT-A77, either after an autofocus operation has been performed (Direct Manual Focus, in Sony parlance), or without any prior autofocus operation. When focusing manually, Sony offers two Focus Magnifier zoom levels to aid in determining the precise point of focus, either 5.9x or 11.7x. Also included is the "focus peaking" display which was introduced in the NEX-C3. This makes it easier to identify the point of focus by highlighting the areas of strongest image contrast. When enabled, three highlight colors are available (white, red, or yellow), and the peaking function can operate at one of three sensitivity levels (high, mid, or low.)

Performance. As well as allowing full-time AF during live view and movie capture, the translucent mirror design of the Sony SLT cameras brings another important advantage. During burst shooting with continuous autofocus, a traditional SLR has to drop its mirror between each frame, wait just long enough for any mirror vibration to settle, perform the AF measurement, and then raise the mirror again so that the next frame can be captured. Using a pellicle mirror, there's no reflex mirror to raise, and so the only delay required is to wait for the lens aperture to open after the exposure has been completed. For even swifter burst shooting, the aperture can be locked at either f/3.5, or the maximum aperture of the lens, whichever is smaller, removing the delay required to set and reset the aperture to allow focusing between shots.

Last year's SLT-A55 was already quite swift, especially with the aperture locked, but the SLT-A77 makes another significant step forwards in shooting speed. Indeed, Sony is claiming the SLT-A77 to be the world's fastest APS-C interchangeable-lens camera, as of August 2011. The standard Continuous Advance drive mode provides two burst-shooting speeds, the higher of which is manufacturer-rated at eight frames per second, up from six frames per second in the A55. (The lower-speed Continuous Advance mode is fixed at three frames per second, slightly faster than the 2.5 fps offered in the A55.) If you're willing to lock the aperture as noted previously by switching to Continuous Priority AE mode, though, you can shoot at a stunning twelve full-resolution frames per second, according to Sony. Again, that's a full two frames per second faster than the A55's spec, despite an increase in resolution from 16.2 to 24.3 megapixels.

Maximum burst depth in the Continuous Hi and Continuous Priority AE modes is rated by Sony as 13 raw or Extra Fine JPEG images, or 11 raw+JPEG frames. The Continuous Hi mode offers one more frame than is available for Continuous Priority AE mode when shooting Fine or Standard-compression JPEGs, achieving 18 frames with either compression level in Continuous Hi, and 17 frames in Continuous Priority AE according to the manufacturer spec.

The SLT-A77 also offers a prefocused shutter release lag of just 0.05 seconds, and although that doesn't quite match the 0.02 second release lag of the latest NEX-series compact system cameras in this area, that's again an exceptionally swift performance.

Visit the A77 Performance page for our timing and performance test results.

Dust reduction. Like the rest of Sony's SLT-series cameras, the Sony A77 includes a two-pronged dust abatement and removal system. First, a charge-protection coating on the low-pass filter aims to prevent dust adhering in the first place. Second, the sensor shift mechanism that's used to provide SteadyShot image stabilization also doubles as a shake mechanism to try and free stubborn dust particles that settle on the low-pass filter, although at much lower frequencies than the vibration induced by cameras using a piezoelectric element. From what we can tell, there is no strategy for keeping dust off the translucent mirror, except to blow the surface gently with air; it should never be touched. A fingerprint would likely require replacement at a service center. The mirror can be flipped up manually so that the sensor can be cleaned, though, just like any DSLR.

The SLT-A77's dust reduction system operates when the camera is switched off, which helps to reduce the startup time, while not relying entirely on the user remembering to manually trigger a dust reduction cycle. It is, however, possible to perform a cycle manually through the menu, if desired.

Environmental sealing. The Sony SLT-A77 includes dust and moisture-resistant seals throughout, including all the main buttons and dials, plus double-layered seals on the card slot, battery compartment, and terminals. The environmental sealing extends not only to the camera body itself, but also to the optional VG-C77AM vertical grip, HVL-F43AM external flash strobe, and the DT 16-50mm F2.8 SSM standard zoom lens, allowing a completely weather-sealed system. The weather sealing doesn't extend to other lenses in Sony's current lineup, however.

Exposure. The Sony SLT-A77 offers a choice of twelve basic operating modes, unchanged from the A55: AUTO, AUTO Advanced (AUTO+), Programmed AE, Aperture-priority, Shutter-priority, Manual, Memory Register (MR), Scene Selection, Sweep Panorama, 3D Sweep Panorama, Continuous Advance Priority AE, and Movie. Scene Selection will automatically set the camera up for one of eight common scene types, as selected by the photographer. Available scene modes are Portrait, Landscape, Macro, Sports Action, Sunset, Night Portrait, Night View, and Hand-held Twilight.

As in Sony's recent cameras, the Hand-held Twilight mode captures six sequential frames with higher sensitivity / shutter speeds to prevent blurring, and then combines them in-camera to yield a single frame with reduced noise levels. The Sweep Panorama modes each capture a burst of images for as long as the shutter button is held down, then automatically stitch them into a panorama. (The 3D mode generates a single image with separate left-eye and right-eye views of the scene, as the subject passes across the field of view). Memory Register mode allows three sets of shooting settings to be saved for later recall.

As with all Sony's Translucent Mirror cameras, the SLT-A77's performs exposure metering using its image sensor. The metering system in the SLT-A77 assesses the metered scene as 1,200 separate zones, and has a working range of EV -2 - 17 at ISO 100 equivalent, with an f/1.4 lens attached. Available metering modes include Multi-segment, Center-weighted, and Spot. As well as locking the metered exposure along with the focus when using multi-segment metering, there's also a dedicated Auto Exposure Lock button.. Exposure compensation is available within a range of 5.0 EV on either side of the metered exposure, in 1/3 or 1/2 EV steps, a much wider range than the +/- 2.0 EV available on earlier models. Additionally, the SLT-A77 can perform three-frame bracketed exposures with a step size of 1/3, 1/2, 2/3, 2, or 3 EV between shots, and five-frame bracketed exposures with 1/2, 1/2, or 2/3 EV between shots.

The Sony SLT-A77 offers a generous selection of thirteen white balance modes, including Auto, nine presets (Daylight, Shade, Cloudy, Incandescent, Warm White Fluorescent, Cool White Fluorescent, Day White Fluorescent, Daylight Fluorescent, and Flash), a direct color temperature setting (2,500 to 9,900 Kelvin), a color filter setting (15-steps of green to magenta bias, and 15-steps of blue to amber bias), plus a Custom white balance mode. There's also a white balance fine adjustment function available.

Available drive modes include Single-shot, Continuous Hi, Continuous Lo, Self-timer (with a delay of two or ten seconds), Continuous Bracketing, Single Bracketing, White Balance Bracketing, DRO Bracketing, and Remote Control (for use with the optional RM-DSLR1 infrared remote control unit). The aforementioned 12-frames-per-second Continuous Priority AE mode gets it own dial position.

Shutter speeds from 1/8,000 to 30 seconds are possible, and the SLT-A77 also offers a bulb shutter function that will hold the shutter open for as long as the shutter button is depressed. Flash sync is at 1/250 second. An optional long-exposure noise reduction function is available for exposures shot with shutter speeds longer than 1 second.

Sony tells us that the A77's shutter is now rated for a life of 150,000 cycles. This is very welcome; with its top continuous-exposure rate of 12 frames/second, those 150,000 cycles will go by faster than you might expect. (Just under three and a half hours of full-tilt 12fps continuous action.) The 150,000 cycle shutter life is on par with cameras like the Canon 7D and Nikon D7000 that the A77 is designed to compete with.

The most noticeable change in the A77's exposure system is its use of an "electronic first curtain." This improves performance while reducing noise and vibration, and is another very welcome addition.

Electronic First Curtain: Fast and quiet. A key technology in all Sony's August 2011 Alpha and NEX announcements is the "electronic first curtain" exposure capability. This greatly speeds the shutter release on live-view cameras, and significantly reduces shutter-generated vibration as well. A little explanation is perhaps in order.

In a conventional SLR, the focal-plane shutter is composed of two leaves or "curtains" that work together to control the exposure time. Think of your camera's sensor as a window with two windowshades; one rolling up from the bottom, the other rolling down from the top. The first curtain starts the exposure by dropping down to uncover the sensor. The second curtain ends the exposure by dropping down to cover it again. After each exposure, the shutter curtains are returned to their original positions in preparation for the next shot. Very short exposures are made by having the two curtains move together, moving a small slit across the focal plane.

To help you visualize, here are a couple of animations showing the action described above, one for a short exposure, the other for a longer one; once the graphic loads, click the button to see the shutter animation. (These animations are from; check out their excellent Textbook of Digital Photography.)

In a live-view camera, the shutter curtains are initially open, so light can reach the sensor to create the live viewfinder display. In live view mode with a conventional mechanical shutter, the bottom curtain has to be raised first, before the exposure can begin. This of course takes time, increasing the shutter lag before the exposure can begin. The closing of the first curtain can also introduce additional vibration, affecting image sharpness at some shutter speeds. (See our detailed discussion of the blur anomaly in the original Olympus E-P1 for an example. The same issue exists to a greater or lesser degree in most mirrorless cameras, though it's all but invisible in some.)

What's new in this latest crop of Sony cameras is that the "first curtain" function is performed electronically. Rather than having to raise the shutter curtain before the exposure, the A77, A65, NEX-7, and NEX-5N all begin the exposure electronically, manipulating voltage levels on the sensor array to enable light-gathering in a progressive wave, sweeping down the sensor's surface.

The most noticeable result of this is that shutter lag in live view mode is very brief: Sony claims only 50 milliseconds (0.05 second), a number closely matching the 53.5 milliseconds we measured electro-optically in our lab. The reduced curtain movement also reduces shutter-induced camera vibration, and makes for a much quieter shutter release as well: The A77's shutter sound is unusually quiet. The electronic first-curtain capability is also likely part of how the A77 achieves its remarkable 12 frames/second continuous burst rate.

This isn't the first time we've seen an electronic first-curtain on an SLR: The Canon 40D introduced the concept back in August of 2007, and as far as we know, Canon live-view-capable SLRs still employ the technology. There's a significant difference in what we call prefocused release lag, though, with Canon's SLRs in Live View mode measuring in the range of 80-90ms, vs the 53.5ms of the Sony A77. In fact, the Sony A77's prefocused lag is very much on par with the fastest conventional SLRs, regardless of price range. Sampling a range of high-performance SLRs, we find shutter release times of 43ms for the Nikon D3s, 49ms for the Canon 1DmkIV, and 53ms for the Nikon D300s. While the Sony A77 doesn't have the absolute shortest release lag, it's very clearly in the top tier, regardless of price.

Tilt level. The Sony A77 includes a dual-axis level gauge, which helps ensure level horizons and prevent converging verticals in photos. The gauge is displayed in a style reminiscent of an aircraft attitude indicator, but with a separation of the roll and pitch indicators. When the camera is perfectly level, the pitch indicators and markings at the end of the roll indicator are illuminated in green.

Built-in GPS. Another less common feature of the Sony SLT-A77 is its built-in GPS receiver, which allows both images and movies to be tagged with information regarding capture location, such as latitude, longitude, altitude, etc. Tagged images can be displayed on a map showing their capture locations, either on a PC using the bundled Picture Motion Browser software, or on the Photo Map function of compatible Sony Bravia TVs. Of course, you can always use third-party software such as Adobe Lightroom or Picasa.

Face detection. Even among SLRs, face detection during live view is a fairly common feature these days. The Sony SLT-A77 goes a step further, though, in offering the ability to register the faces of eight specific individuals, who will then be automatically recognized and prioritized over other faces when determining focus, exposure, and flash output, as well as during post-exposure image processing. The SLT-A77 is capable of simultaneously detecting and accounting for up to eight faces in any given scene, and also includes a Smile Shutter function with three-step sensitivity, which will automatically capture an image when your subject is smiling. Of course, face detection can be disabled, should you wish.

Flash. The Sony SLT-A77 includes an auto-popup flash strobe, slightly improved from that in the A55. The guide number is now 12 meters (39.4 feet) at ISO 100, coverage is rated at 16mm, and the recycle time is rated at three seconds, as compared to the A55's guide number of 10 meters (32.8 feet) at ISO 100, 18mm coverage, and four-second recycle.

Available built-in flash modes include Off, Auto, Fill, Rear-sync, and Slow-sync, and an optional red-eye reduction function is available. Flash metering modes include ADI and pre-flash TTL, as well as manual output control being available (1/1, 1/2, 1/4, 1/8 or 1/16 power). +/-3 EV of flash exposure compensation is available, in 1/3 EV steps, and flash exposures can also be bracketed, with five frames varying by 1/3, 1/2 or 2/3 EV, or three frames varying by 1/3, 1/2, 2/3, 2, or 3 EV.

The A77's popup flash can also serve as a wireless controller. Some external strobes including the HVL-F36AM, HVL-F42AM, HVL-F56AM, and HVL-F58AM support high-speed sync and wireless shooting.

As with the earlier SLT-series cameras, the A77 also includes a proprietary flash hot shoe, but the pro-oriented SLT-A77 adds a standard PC sync terminal for connecting studio strobes. PC sync voltage supported is up to 400 volts.

Creative. The Sony SLT-A77 includes quite a range of creative controls to help photographers get the look they're after, with a minimum of time spent in the digital darkroom. A selection of eleven Picture Effect modes are available, five of them new since the SLT-A33 (with one mode having been removed.) The new modes include Soft High-key (which replaces the A33's High-key mode), plus Soft Focus, HDR Painting, Rich-tone Monochrome, and Miniature. The Posterization (color or black & white), Pop Color, Retro Photo, Partial Color (red, green, blue , or yellow), High Contrast Mono, and Toy Camera modes are all held over from the earlier camera. (The A55 and A35 also have the same Picture Effect modes as the A33 in current firmware, but didn't ship with this feature at launch.)

In addition, the SLT-A77 provides an enlarged selection of Creative Style choices as compared to the A55, each of which offers +/- three-step control over contrast, saturation, and sharpness. New Creative Style modes include Neutral, Clear, Deep, Light, Night Scene, Autumn Leaves, and Sepia, in addition to the existing Standard, Vivid, Portrait, Landscape, Sunset, and Black & White modes from the A55.

A Dynamic Range Optimizer function aims to open up the shadows while maintaining highlight detail, and can be left under automatic control, or set to one of five preset levels. There are also several multi-shot modes, including Hand-held Twilight (which allows faster shutter speeds with reduced image noise), and an Auto HDR mode. This last creates a single high dynamic range image from three sequential shots, whose exposure level varies anywhere from 1 - 6 EV in 1 EV steps, controlled automatically or manually.

The SLT-A77 also offers an in-camera Sweep Panorama function, which captures and stitches together multiple images as you sweep your lens across a panoramic scene. When set to Wide mode, Sweep Panorama can create a horizontal scene with a resolution of 12,416 x 1,856 pixels, or a vertical scene with a resolution of 2,160 x 5,536 pixels. In standard mode, the horizontal dimensions are 8,192 x 1,856 pixels, while vertical panoramas occupy 2,160 x 3,872 pixels.

3D Imaging. In addition to the standard Sweep Panorama function, the SLT-A77 includes a 3D Sweep Panorama mode. Since it only has objective lens, the stereo effect is created using some clever mathematics to reconstruct a 3D image as the subject passes across the lens' field of view. The result is saved as a single multi-picture object file that contains two separate JPEG images, one for each eye, allowing it to be viewed on 3D-capable Sony Bravia displays In Wide mode, 3D Sweep Panoramas occupy 7,152 x 1,080 pixels, while in Standard mode the resolution is 4,912 x 1,080 pixels. There's also a 16:9 mode, which saves a 1,920 x 1,080 pixel panorama suitable for full-screen HDTV viewing.

Video. The Sony SLT-A77 also offers Full HD (1,920 x 1,080 pixel) video capture capabilities, and according to Sony, is the world's first interchangeable-lens camera (along with other Sony models simultaneously announced) able to record Full HD off the sensor at 60 frames per second. (We've seen cameras previously which recorded 60 interlaced fields per second at Full HD resolution, but these either clocked the data off the sensor at 30 frames per second and then split each frame across two interlaced fields, or they clocked the data at 60 frames per second but discarded alternating fields, to be compliant with the original AVCHD 1080 60i specification.)

The SLT-A77's Full HD video is recorded using AVCHD Version 2.0 compression, with Dolby Digital (AC-3) audio, and a wide range of progressive-scan and interlaced frame rates are available. When set to NTSC mode, the available progressive-scan rate are 60 fps (28Mbps) or 24 fps (24 Mbps or 17 Mbps), and you can also opt for an interlaced 60 fps (24 Mbps or 17 Mbps). If you switch to PAL mode, the options are the same, except that the 60 fps rates are replaced by 50 fps equivalents, and the 24 fps rates by 25 fps ones.

It's also possible to record at a high-def resolution of 1,440 x 1,080 pixels (12 Mbps), or a standard-definition VGA (640 x 480 pixel, 3Mbps) resolution. These are all available at 30 fps in NTSC mode, or 25 fps in PAL mode, and are captured using MPEG-4 AVC (H.264) compression with MPEG-4 AAC-LC audio. Note that no 720p recording mode is available on the SLT-A77.

The most unusual capability of the Sony A77's video mode is enabled by its translucent mirror. The Sony A77 can continue to use phase detection autofocusing during movie recording, allowing swift adjustments to focus as your subject moves. Since standard Alpha-mount lenses are used, this focusing action is accompanied by significant levels of autofocus drive noise, although Sony notes that it has included a new noise reduction algorithm intended to suppress this AF drive noise. For consumers, any remaining drive noise is likely a relatively small price to pay for sharply focused video, however, given that manually pulling focus during video capture is a difficult art to learn.

Also unlike many competing cameras, the Sony SLT-A77 provides full control over movie exposure, with a choice of Program, Aperture-priority, Shutter-priority, or fully Manual recording. It also allows Tracking autofocus, as well as use of Creative Style and some Picture Effect modes during movie capture. Recording is started and stopped with a dedicated Movie button on the SLT-A77's rear panel, and audio is captured by default with a built-in stereo microphone. There's also an external stereo microphone jack, compatible with microphones including Sony's own ECM-CG50 Shotgun Mic and ECM-ALST1 Stereo Mic. A built-in monaural speaker caters to movie playback, and has an eight-step adjustable volume setting.

See the A77 Video page for sample videos and more details.

Playback. To let you immediately judge composition, exposure, and the like, the Sony SLT-A77 provides an optional Auto Review function that can display images on-screen for two, five, or ten seconds immediately post capture. (There's also a Shot Result Preview function in Record mode which lets you see an image as it would be captured with the current settings, including shutter speed, DRO settings, etc.) After capture, Playback mode lets you review single images, with optional shooting information, RGB histogram, or blinking highlight/shadow warning. In addition, images can be enlarged up to 13.6x to confirm fine details. Two index views are available, showing either four or nine frames at once.

Connectivity. The Sony SLT-A77 includes a USB 2.0 High Speed data connection, allowing for transfer of images and movies to a personal computer. Two operating modes are available for the USB connection, either USB Mass Storage Class, or Microsoft's Media Transfer Protocol. Catering for high-definition video output, the SLT-A77 also provides a Type-C Mini HDMI connection, with support for Bravia Sync, Sony's brand name for the Consumer Electronics Control standard. This allows certain playback functions such as switching between images to be performed using the attached display's remote control unit. There's no standard-definition video output on the SLT-A77, though, so photographers who've yet to switch to a high-def display will need a third-party device with which to view images on a standard TV.

Other connectivity on the SLT-A77 includes a DC Input for the optional AC adapter, a flash sync terminal and hot shoe, and jacks for both an external stereo microphone, and a wired remote control unit.

Storage. As well as Sony's proprietary Memory Stick PRO Duo and Memory Stick PRO-HG Duo flash cards, the SLT-A77's single card slot supports Secure Digital cards, including not only the higher-capacity SDHC and SDXC types, but also the higher-speed UHS-I compliant cards. 2D images can be saved either in Sony ARW 2.3 raw format, or as standard JPEG files (DCF Ver. 2.0, Exif Ver. 2.3, MPF Baseline compliant). 3D images are saved as Multi Picture Object files (MPF Extended compliant).

Battery. The Sony SLT-A77 draws power from a proprietary NP-FM500H lithium-ion battery pack, which is rated by Sony for 470 shots when using the electronic viewfinder, and 530 shots with the LCD monitor, to CIPA testing standards.

An available VG-C77AM vertical grip not only provides duplicates of the main controls for portrait-orientation shooting, but also accepts two NP-FM500H battery packs, roughly doubling battery life (since the in-camera battery pack can't be used with the grip connected).

Sony A77 Image Quality

Since the Sony A77 has now taken the APS-C resolution crown, we're comparing it here to two of its biggest competitors, the Canon 60D and Nikon D7000 and two full-frame cameras of similar resolution, in this case the Nikon D3X and Sony A850. Though we normally start with ISO 1,600 here, we thought we'd start with ISO 100 to show the best it can do.

Note: These crops have been updated from the original v0.58 firmware on our prototype A77 to v1.03 firmware from a full production-level unit. Also note that these images are best quality JPEGs straight out of the camera, at default settings including noise reduction. All cameras in this comparison were shot with our very sharp reference lens, the Sigma 70mm f/2.8 EX DG Macro.

Sony A77 versus Canon EOS 60D at ISO 100

Sony A77 at ISO 100
Canon 60D at ISO 100

The Sony A77 does quite well against the Canon 60D, which is not a huge surprise at ISO 100 considering what happens when you pit a 24.3-megapixel sensor against an 18-megapixel design. Both look great, but the Sony resolves more. You can see hints of a thread pattern in the Canon 60D, but it's better defined from the A77.

Sony A77 versus Nikon D7000 at ISO 100

Sony A77 at ISO 100
Nikon D7000 at ISO 100

The A77 also surpasses the 16.2-megapixel Nikon D7000, bringing out significantly more detail from our test target. What happens as ISO rises will be interesting.

Sony A77 versus Nikon D3X at ISO 100

Sony A77 at ISO 100
Nikon D3X at ISO 100

The Sony A77 also does well against the $8,000 full-frame D3X. The D3X looks a little more crisp, but simple sharpening could help that.

Sony A77 versus Sony A850 at ISO 100

Sony A77 at ISO 100
Sony A850 at ISO 100

Here we have the crop-frame A77 against Sony's full-frame A850. It seems to come down to a difference of contrast, maybe even exposure. The pink fabric below the red leaf swatch has more texture, which you'd expect from a larger sensor, and truer color. Overall, the A77 looks quite comparable.

Most digital SLRs will produce a reasonable ISO 100 shot, so we like to push them and see what they can do compared to other cameras at ISO 1,600, 3,200, and 6,400. Recent advances in sensor technology have made ISO 1,600 look a lot more like ISO 100, but there are still cameras whose quality starts to fall apart at this setting. We also choose 1,600 because we like to be able to shoot at least at this level when indoors and at night.

Sony A77 versus Canon 60D at ISO 1,600

Sony A77 at ISO 1,600
Canon 60D at ISO 1,600

ISO 1,600 confirms the reason we do these crops, as the Sony A77 starts to struggle with detail at this setting thanks to aggressive noise suppression, particularly in the mosaic crop. The Canon 60D maintains a little more detail, but not a lot, also struggling with the red leaf swatch. The A77 with the latest 1.03 firmware does a lot better in the red leaf swatch, producing a comparably muddled, if differently rendered image.

Sony A77 versus Nikon D7000 at ISO 1,600

Sony A77 at ISO 1,600
Nikon D7000 at ISO 1,600

It's probably a toss-up between the two, given the A77's heavier noise suppression against Nikon's lower detail at 16 megapixels. But there's no question that the Nikon D7000 renders the red leaf swatch a lot better than the Sony A77, even with the new firmware. Nikon still takes a more even hand balancing noise suppression against sharpening, creating a more realistic rendering than most other manufacturers at this point.

Sony A77 versus Nikon D3X at ISO 1,600

Sony A77 at ISO 1,600
Nikon D3X at ISO 1,600

Again, noise suppression in the A77 limits detail in all three crops when compared to the Nikon D3X, which has legendary performance in low light. Still, this is quite good performance from an APS-C sensor compared to a full-frame.

Sony A77 versus Sony A850 at ISO 1,600

Sony A77 at ISO 1,600
Sony A850 at ISO 1,600

Here the Sony A77 surpasses somewhat, doing a better job with background chroma noise and the mosaic image than its larger cousin the A850. But both the A900 and A850 didn't do as well at higher ISOs, so it's not much of a surprise. Note that the A850 still does a slightly better job on the red leaf swatch.

Today's ISO 3,200 is yesterday's ISO 1,600 (well, almost), so below are the same crops at ISO 3,200.

Sony A77 versus Canon EOS 60D at ISO 3,200

Sony A77 at ISO 3,200
Canon 60D at ISO 3,200

Except for color, it seems both cameras render about the same detail at ISO 3,200, though the A77 with the new firmware does a better job with the red swatch. The Canon retains a little bit more subtle color, if it's a little pumped by comparison. Very close.

Sony A77 versus Nikon D7000 at ISO 3,200

Sony A77 at ISO 3,200
Nikon D7000 at ISO 3,200

Sony cleans up the chroma noise a little more thoroughly, omitting color artifacts that show up noticeably in the shoulder of the olive oil bottle above in the D7000 image. But the Nikon D7000 looks a little better on the mosaic image, and does a better job capturing the essence of the red leaf swatch.

Sony A77 versus Nikon D3X at ISO 3,200

Sony A77 at ISO 3,200
Nikon D3X at ISO 3,200

The Nikon D3X maintains a lot more color as well as detail. The A77's rendering is still respectable, but again shows the disadvantage of a smaller sensor size.

Sony A77 versus Sony A850 at ISO 3,200

Sony A77 at ISO 3,200
Sony A850 at ISO 3,200

The Sony A77's image looks a little cleaner than that of the A850, with less blotchy noise, though the A850 renders the read leaf swatch a little better. I prefer the A77's image.

Detail: Sony A77 vs. Canon 60D, Nikon D7000, Nikon D3X, and Sony A850

ISO 100
ISO 3,200
ISO 6,400
ISO 100
ISO 3,200
ISO 6,400

ISO 100
ISO 3,200
ISO 6,400
ISO 100
ISO 3,200
ISO 6,400
ISO 100
ISO 3,200
ISO 6,400
Detail comparison. High-contrast details are often sharper as ISO rises, so they're worth a look as well. Base ISO detail looks good from all five cameras, with the A77 looking slightly soft but not significantly so. The Nikon D7000 also doesn't quite render the lines inside the letters as well as the others due to its lower resolution of 16 megapixels. At ISO 3,200 you can see some decay in quality from the A77 even when compared to the A850, though the A850 shows color splotches where we know there are none. At ISO 6,400 the Sony A77 doesn't do quite as well as the others with the fine lines or the red letters. Still, for the price -- and even the camera's size -- the Sony A77 does very well.


Sony A77 firmware 0.58 vs 1.03

Below are crops comparing the red leaf swatch at ISO 3,200 with the prototype and production camera.

Sony A77 v. 0.58 at ISO 3,200
Sony A77 v. 1.03 at ISO 3,200

Sony's production firmware makes an improvement in the rendering of the very difficult red leaf swatch, so clearly they have improved their red-channel processing. There was little improvement in the other channels, so other elements of our test crops remained essentially unchanged.

Sony A77 Print Quality

100% crops on-screen can only tell you so much, especially when comparing cameras of different resolutions. So we always print samples of various sizes to determine the maximum print size at each ISO setting. To avoid printing massive stacks, we print only JPEGs generated from our test images taken at default noise suppression settings. Usually you can get quite a bit more processing the images from RAW.

Note: This is an updated print quality analysis based on images printed with the firmware version installed when the production-level lab shots were taken (v1.03), revealing a slight increase in overall quality from the pre-production version (v0.58) .

ISO 50/100 prints look quite good at 30 x 40 and terrific at 24 x 36.

ISO 200 prints are again excellent at 24 x 36 inches.

ISO 400 prints are also good at 24 x 36 inches.

ISO 800 shots print quite well at 20 x 30 inches.

ISO 1,600 shots look great at 16 x 20, although hints of noise appear in light shadows.

ISO 3,200 makes a nice 11 x 14 inch print, although there is some large, diffuse chroma noise in areas of flat tints.

ISO 6,400 images are usable at 8 x 10, if a little rough in some spots. We prefer the 5 x 7 images.

ISO 12,800 and 16,000 do not produce usable prints and are best avoided.

Overall, the Sony A77's image quality is excellent. Once we installed the updated firmware and reshot and printed the updated images, we were able to give slightly higher recommendations at several ISO settings than we were able to give with the prototype, based mainly on the update's ability to more accurately render data in the red channel.


In the Box

The retail kit contains the following items:

  • Sony Alpha SLT-A77V body
  • SAL1650 SAM lens with lens cap, if bought as a kit
  • Lithium-ion battery pack NP-FM500H
  • Battery charger
  • USB cable
  • Body cap
  • Shoulder strap
  • Software CD-ROM


Recommended Accessories

  • Extra battery pack for extended outings
  • Fast, large capacity SDHC/SDXC or Memory Stick Pro-HG Duo memory cards. These days, 8-16GB is a good trade-off between cost and capacity.
  • Camera case
  • Additional lens(es)
  • External flash


Sony Alpha A77 Conclusion

Pros: Cons:
  • 24.3-megapixel APS-C sensor offers great resolution for a prosumer DSLR
  • Unique Sony translucent-mirror tech provides full-time phase-detect autofocus
  • Full-time live view by default
  • 12 frames-per-second capture rate
  • Fast autofocus, burst, shutter lag, shot-to-shot and continuous mode speeds
  • Full 1080p HD video recording, at up to 60 frames per second
  • 60fps video mode is true 60fps from the sensor, not frame-doubled 30fps
  • Live phase-detect autofocus during video recording (but see notes under Cons)
  • Supports both AVCHD and MPEG-4 video formats
  • Full PASM exposure control in video mode (but see note under Cons)
  • Stereo audio recording via built-in mic or standard 3.5mm external jack
  • Very good body-based image stabilization
  • Tons of creative modes and filters, including Sony's Sweep Panorama
  • Very good 2.4 million dot EVF (OLED technology)
  • Articulating 3-inch, 921,600-dot LCD is bright and viewable in all lighting conditions
  • Excellent 16-50mm f/2.8 zoom kit lens
  • Solid magnesium alloy molded body
  • Comfortable, ergonomic build and easy-to-operate controls
  • Popup flash can also serve as a wireless controller
  • Built-in GPS
  • Good battery life for an interchangeable lens camera equipped with an EVF (but see note under Cons)
  • Somewhat heavy for a prosumer DSLR
  • Uses an EVF instead of an optical viewfinder; EVF appears dim when used in bright light
  • Camera doesn't switch fast enough between the LCD viewfinder and EVF after viewfinder detects you're looking through it, leaving you in the dark for a brief moment
  • Images sometimes a little underexposed
  • Noise suppression gets in the way of truly sharp pictures at ISO 1,600 and above
  • Continuous AF in Movie mode only works with large apertures and isn't available in aperture priority, shutter priority, or manual exposure modes
  • AF tracking in Movie mode was unreliable in our testing
  • Movie-mode aperture priority, shutter priority, and manual exposure modes are only available with manual focus
  • Max ISO sensitivity limited to 1,600 in movie mode
  • Video images are cropped significantly from full sensor area, makes wide-angle video harder to achieve
  • EVF is still an EVF, dynamic range doesn't match that of the human eye
  • Below average battery life compared to traditional DSLRs with optical viewfinder


The Sony Alpha A77 is a major leap forward for the company in DSLR design, features and image capabilities, finally putting Sony into the competitive mix with Canon and Nikon in the prosumer DSLR marketplace. The A77's 24.3-megapixel APS-C sensor, Translucent Mirror Technology and 12 frames-per-second capture rate changed everything for Sony. I found the Sony A77 to be solidly built, with a comfortable, familiar feel very reminiscent of the ergonomics of past Canon DSLRs-- which is a good thing. The A77 is very fast on almost all accounts, including autofocus, shutter lag and shot-to-shot speeds. As you'd expect with the high-resolution sensor, the A77's image (and print) quality is excellent, and the 16-50mm f/2.8 zoom kit lens provides excellent optics and performance beyond that of most kit lenses. Our laboratory testing did show that the A77's heavy-handed noise reduction robbed a little fine detail when shooting at ISOs of 1,600 and above. Another downside was the lack of an optical viewfinder. While the EVF does allow Sony to pack more performance into the sensor and internal electronics, I found it somewhat difficult to deal with; it was often dim when used in bright light, and didn't switch over from the LCD fast enough after it detected I was using the EVF. Additionally, when I took the camera out for some test shots, I found that sometimes my images were slightly underexposed, but nothing I couldn't fix afterward in Photoshop. Despite these negatives, I hadn't been excited about a DSLR as I was with the A77 in a long, long time. And Sony more than lived up to my high expectations. The rare combination of superior design and build, excellent imaging, fast shooting speeds, tons of creative modes, Full HD video recording and much more make the Sony A77 a definitive Dave's Pick.

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