Introduction, Features, Build and Performance
After the announcement of the full-frame E-mount Sony A7, A7R and A7S compact system cameras and the demise of the Nex brand, you could be forgiven for thinking that Sony may not continue with its A-mount SLT (single lens translucent) cameras. However, the Sony Alpha 77 II proves this not to be the case.
As you might guess, the Alpha 77 Mk2 replaces the Alpha 77, which is now discontinued, and it has an almost identical shape and design. The new camera is aimed at enthusiast photographers who want a step-up from an entry-level model.
Features
Like the Alpha 77, the A77 Mark II has a 24 million-pixel sensor, but this is a new device that benefits from the progress that has been made with sensor design in the two-and-half-plus years since the A77 first arrived.
For the first time in an A-mount camera, the signal from the Exmor sensor is processed by a Bionz X processor. This should mean that the A77 Mark II is capable of resolving a high level of detail and controlling noise at high sensitivity settings.
Sensitivity may be set in the native range ISO 100-25,600 for still images, with a low expansion setting of ISO 50 being availble. The movie sensitivity range is a bit narrower, going from ISO 100 to 12,800.
As the SLT design has a fixed translucent mirror, the A77 Mark II has an electronic rather than optical viewfinder. Sony has used the same 2.3 million-dot OLED Tru-Finder as is found in the A7 and 7R, which is good news since this provides a clear, detailed view.
This viewfinder also allows enlargement to assist with manual focusing and can display focus peaking and zebras to indicate areas of highest contrast (sharpness).
One of the benefits of the SLT design is that there can be full-time phase detection autofocus during movie shooting and when composing images on the rear screen. Sony has used a newly developed phase detection sensor in the Alpha 77 Mark II. This has 79 AF points, 15 of which are the more sensitive cross-type. In comparison, the original A77 has 19 AF points of which 11 are cross-type.
The new camera can also shoot a maximum rate of 12 frames per second (fps) with AF tracking and the buffer has capacity to allow up to 25 raw and JPEG images to be captured in a single burst. The original Alpha 77 could only cope with 11 images in a burst at 12fps. If raw file recording is deactivated, the A77 Mark II can record around 53 Extra Fine JPEGs in one blast.
Although autofocusing and auto exposure continues when shooting at 12fps, aperture is locked at the start of the sequence. If exposure needs to change during the burst it is done via shutter speed or sensitivity.
Sony is rather proud of the progress it has made with the autofocusing system for the A77 Mark II. We're told that five engineers conducted field tests for six months with high-end cameras like the Canon EOS-1DX, Canon 70D, Nikon D4, Nikon D7100 and Panasonic GH3, in order to find the best parameters for AF while shooting a variety of sports and action.
Sensor development means that the A77 Mark II's CCD AF sensor produces less electronic noise than previous devices and this helps with autofocusing speed and accuracy as well as boosting low-light performance. Spot AF performance is also claimed to have been improved with weighting given to the centre of the spot.
The A77 Mark II has a collection of AF-point selection options including Wide, Zone, Flexible Spot, Local, Expanded Flexible Spot and Lock-on AF. In Expanded Flexible Spot mode the photographer selects one AF point and the camera supports this with the surrounding 8 points. In Zone AF mode the AF points are divided into 9 zones for selection.
Lock-on AF allows the user to specify how quickly the camera responds to changes in subject distance. In the past this was located in the menu, but it has been moved to the AF Mode selection area to make it quicker and easier to find.
According to Sony, almost all of its A-mount lenses are compatible with the 79 AF points, but only 61 are available when shooting at 12fps. Sony's 500mm f/8 lens is a notable, but not surprising, exception and it will only allow the center AF point to be used.
Other pleasant additions to the Alpha 77 Mark II's featureset include an HDMI port that can supply clean video output to external storage devices and Wi-Fi connectivity. As the A77 Mark II has an NFC chip, owners of NFC enabled smartphones and tablets can connect to the camera by touching the two devices together.
Interestingly, despite the presence of Wi-Fi connectivity, the A77 Mark II cannot make use of aSony PlayMemories Camera apps.
Build quality and handling
Close comparison of a pre-production sample Alpha 77 Mark II with the original Alpha 77 reveals few obvious differences. The two cameras have the same overall shape and control layout and the vertical grip that was produced for the original A77 can be used with the new camera.
There is a slight difference to the new camera's mode dial, however: it has a lock button to prevent it from being knocked out of position. The hotshoe has also been changed from the Sony (Minolta) proprietary shape to the more common universal style. It has also been upgraded to make it a multi-shoe capable of accepting a range of accessories.
In addition, the function (Fn) button has a greater range of customisation options.
Like the camera it replaced, the Alpha 77 Mark II feels pretty tough and durable. The grip on the front of the camera is deep and generously sized to provide a comfortable hold. There are also plenty of buttons and dials to give direct access to many of the key features, as befits an enthusiast-level camera.
Strangely, Sony has continued with having the 12fps shooting option located on the mode dial. Given the rethinking about the AF options, we might have expected this to be part of the drive mode options. Sony's explanation is that it's a major feature of the camera and that there are aspects such as the aperture locking at the start of the shoot that need to be considered.
On the back of the camera is a three-inch vari-angle screen, which provides a detailed, clear view of the scene, but isn't touch-sensitive. Its resolution, however, has been boosted from 921,000 dots to 1,228,000 dots.
As on the Sony A7 and 7R, the 2.3-million dot electronic viewfinder is bright and clear with plenty of detail visible.
Performance
As yet we have only been able to use a sample of the Sony Alpha 77 Mark II for a short while, but we have been able to look at a few images from it, which are published on the next page.
The early signs are good, and Sony's strong reputation for sensor design and image processing looks set to continue. However, some of the images captured at the lower sensitivity settings have slight coloured speckling that is visible at 100% on-screen. They look very good at normal veiwing sizes however, and there's plenty of detail in shots taken in the low to middle sensitivity range.
Our initial images taken at the highest sensitivity level (ISO 25,600) also look good at normal viewing sizes, although there is smoothing of noise evident at 100% on screen. I'm looking forward to testing the camera in a wider range of light levels.
Colours look natural direct from the camera and the automatic white balance copes well with a mixture of natural and artificial light.
Naturally, we have also seen some of Sony's sample images from the A77 Mark II and they look good, prompting Sony to claim that noise levels are lower than from competing cameras.
Sony's Bionz X processing engine has diffraction reducing technology to improve JPEG resolution and sharpness and it will be interesting to see how this impacts upon image quality from the A77 Mark II in comparison with the A77.
We haven't been able to test the A77MK2's autofocusing system fully by any means, but my initial impressions are very good. It seems fast and accurate even in subdued light and is capable of keeping a moving subject sharp. It also follows faces around the frame accurately.
Early verdict
While the changes made with the Alpha 77 Mark II may not seem dramatic, Sony has worked on the most important aspects – the sensor and processor – to boost speed and image quality.
Many will recognise that it's sensible to stick with the same pixel count as with the Alpha 77, as 24 million captures enough detail for most purposes and allows big prints to be made. The files are also large without being unmanageable by the average modern computer.
We're looking forward to getting a full-production sample of the A77 Mk II in so that we can test the improved autofocus system and see if it is a match for a high-end SLR's when shooting sport and action.
Naturally, we'll also investigate all other aspects of image quality including exposure metering, white balance and colour, but given Sony's claims we'll be paying particularly close attention to the noise levels at high sensitivity values. We're also looking forward to putting the AF system through its paces.
Sample images
This ISO 800 image has a very impressive level of detail.
Though smoothing is visible when the image is viewed at 100% on-screen, this ISO 25,600 image looks very good at more normal viewing sizes.
Colours are rich, yet natural and there's a pleasing level of contrast straight from the camera.
The A77 Mark II has handled the exposure well here, and there's plenty of detail in the feathers on this bird.
The A77 Mark II's metering system has concentrated on the most important aspect of this scene and not been overly put-off by the bright sky.
There's some coloured speckling visible in the shadow areas of this ISO 250 image.
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