Sony Alpha A77 review
Sony Alpha A77 review - Image Quality
A77: Tone and Exposure
The Alpha A77 uses a 1200-zone evaluative metering system, with a choice of either Multi segment, Centre-weighted or spot metering modes on offer. Even in high contrast scenes, the Multi segment metering of the A77 performed very well, delivering well exposed images. It was only every now and again that a minor increase in exposure compensation was needed to counteract slightly underexposed images.
Images display a smooth tonal range, while there's the D-Range Optimiser to rescue detail in the highlights and shadows of high-contrast, backlit scenes. There are five levels to choose from, as well an Auto mode. However, it's worth mentioning that this is a JPEG-only shooting option.
A77: White Balance and Colour
The A77's Auto White Balance performed consistently well, delivering pleasing results with a minor warm tint to them, which was not undesirable. On top of that, you've got the choice of Daylight, Shade, Cloudy, Incandescent, Fluorescent (four variations), Flash and Kelvin white balance modes. There's also a Custom option too, with the ability to store three presets.
There're also a choice of Creative Styles to alter the intensity of the colours - as well as Standard, there are Vivid, Neutral, Portrait, Landscape and Black & White options. These can all be fine-tuned, with adjustments for contrast, saturation and sharpness.
A77: Sharpness and Detail
The Alpha A77 uses a completely new sensor. The 24.3MP APS-C type CMOS sensor delivers files that can be around 10MB in size (or 68MB when opened in Photoshop), while Raw files take up 25MB. While this may not sound a lot, shooting a stack of Raw files will soon chew up a far amount of space on a card. The large resolution will allow you to print images at A2 at 240dpi without the need to upscale the image should you wish, so A3+ prints are easily achievable at 300dpi.
Detail and sharpness are both excellent, but it's worth bearing in mind that you won't see a massive leap in resolving power compared to results from a 16MP or 18MP chip.
A77: ISO Quality
The Alpha A77 has a native ISO range from ISO 100-16,000, which can be expanded to shoot at an equivalent ISO of 50 - handy when long exposures are desired or there's an abundance of light.
With this kind of pixel count, there's a worry that image noise will become more pronounced as more photodiodes are crammed onto a sensor of the same size. Taking that into consideration, and the Alpha A77 performs very well. From the base ISO to 3200, results display very minimal levels of image noise. As you'd expect, above that, and image noise creeps in and becomes more prominent - ISO 12,800 and 16,000 should only really be used as a last resort.
The Alpha A77's Raw files are compatible with Adobe Camera Raw 6.5 (and Lightroom 3.5), with an update downloadable from Adobe's website. The Alpha A77 is also bundled with Image Data Converter (Ver 4.0), allowing you to process Raw files directly if you don't have an alternative image-editing program. JPEG files have obviously have had some processing applied to them - colours are more saturated, with a mild level of sharpening.
A77: Movie Mode
The AVCHD movie footage shot on the Alpha A77 requires you to process the majority of its footage via the supplied PMB software before the footage can be viewed/edited. Depending on your machine and the length of your footage, this can take a while.
Video footage is great though - with a rate of around 28Mbits/sec at 50p and 24Mbits/sec at 24p. The sound quality is pretty g
ood for an onboard stereo mic, but an external microphone attached via the 3.5mm jack is recommended for those wanting a crisper sound.