Sony Alpha 580 at a glance:
- 16.2-million-effective-pixel CMOS sensor
- Seven frames per second
- ISO 100-12,800 (expandable to 25,600)
- 1080i HD video
- Folding LCD screen
- Street price around £640 with 18-55mm lens
Sony Alpha 580 review – Introduction
When Sony announced the launch of four new Alpha cameras in August last year, it was the single lens translucent (SLT) technology that grabbed most of the attention. This old idea that had revolutionised autofocus was made more usable through the inclusion of an electronic viewfinder. Yet almost as a fail-safe, the company created an alternative for those who might not be taken by SLT technology, in the form of a ‘conventional’ DSLR.
The Sony Alpha 580 is one of those alternatives, and one of two new models that replace the year-old Alpha 500 and 550 DSLRs. The lesser specified Alpha 500 has been superseded by the Alpha 560, with the Alpha 580 replacing the Alpha 550.
The older two cameras had little to separate them, and now there is even less to discern between the two newcomers. The Sony Alpha 580 does have two million more pixels than the Alpha 560, housing as it does a 16.2-million-pixel sensor, but all other key features are identical, including body size and weight. So, with the exception of the sensor and resolution, all that is written in this review can also be applied to the Alpha 560.
Sony’s Alpha 580 logically sits in its DSLR range between the Alpha 390 and Alpha 700, but the four new models crowd one particular area of the market, offering comparable features and commanding similar price tags. It becomes a challenge for any entry- or enthusiast-level DSLR user to discern just who each camera is aimed at, because aside from the SLT technology in two of the models, each camera incorporates many of the same refinements.
It will be interesting to see whether the Alpha 580 would best be viewed as a back-up to the SLT models, or if it offers enough improvement over its predecessor and its lesser counterpart (the Alpha 560) to make it worthwhile splashing a little extra cash.
Features
The Alpha 580 does benefit from a couple of noticeable improvements over its predecessor. It employs a 16.2-million-effective-pixel Exmor APS-C HD CMOS sensor (the same as that found in the Alpha 55), which is an increase of two million pixels.
The lack of video was a rather obvious omission in the earlier Alpha 550, and Sony has remedied it by introducing HD video into the Alpha 580 for the first time in a conventional Sony Alpha DSLR.
As with the Alpha 55, the Alpha 580 features a new 15-point AF system, with six more points than featured in the Alpha 550, including three of the more sensitive cross-type. As before, users can choose between phase-detection and contrast-detection AF.
One key difference between Sony’s conventional Alpha DSLRs and its SLT cameras is that the former still uses an optical viewfinder. A two-mode live view system in the Alpha 580 includes a focus-check mode, which is useful for previewing exposure and focus. In-camera SteadyShot means there is no need for image stabilisation in the lens, and Sony claims it can offer up to a 4EV decrease in handholdable shutter speeds.
Seven frames per second is clearly a selling point and can be achieved using the speed-priority continuous-drive mode. However, while in this mode both focus and exposure are fixed. To retain AF and exposure control, the high-speed burst drive mode must be used, although this operates at only 5fps when using the viewfinder, and just 3fps when in live view.
Image: Panorama sweep modes are new to the Alpha DSLR range and can add a little extra to your landscapes. Customisable sizes for horizontal panoramas reach up to 12,416×1856 pixels and 7152×1080 pixels in 3D mode
Sweep panorama mode, which appears in Sony’s Cyber-shot and NEX range, has also been introduced here. There is a 3D option available, too, which literally adds another dimension to panoramic photographs. In this mode the exposure is automatic, but it can be fixed satisfactorily by using the auto exposure lock.
Sensitivity can be increased to ISO 25,600 using the multi-frame noise-reduction mode, and both this feature and the handheld twilight scene mode take advantage of the fast frame rate to combine several exposures for low-noise results. The auto HDR mode has also been refined and offers up to a 6EV dynamic range boost.
Build and handling
Users will find it difficult to notice any external changes from the Alpha 550 to the Alpha 580. The size, weight and button layout of each is almost identical, with the exception of a lone movie record button on the newer model, and ISO and drive mode buttons that have edged closer to the shutter.
This is a more convenient position for index-finger control when using the viewfinder, as there is no need to remove your eye to operate it. The combination of rubber grips and plastic body feels durable, and the Alpha 580 sits nicely in the hand, although users with longer fingers may not find the grip deep enough.
A well-thought-out button layout encourages the use of some key features. The D-range button (through which the HDR mode is accessed) and exposure-compensation buttons are prominently placed just above the rear screen.
The main menu has very little to it, because most of the controls can be accessed through the function button menu. Usefully, all that is needed to get the most out of the camera’s fast frame rate is found here, such as the drive mode (including speed priority), AF area and AF mode.
Using two hinges, the folding screen allows for shooting near to ground level and above head height. It feels solid and durable, but its single-dimensional fold of a little over 90° up and 90° down is restricted to vertical movement. Frustratingly, the two playback modes, one of which is for photos and the other for videos, cannot be mixed. Changing file type playback is achieved via the main menu.
Both the mirror slap from the shutter and the pop-up flash are a little loud and clunky, so discreet shooting is not really possible, particularly during a high-speed burst.
Once a burst has been captured, the new Bionz image processor takes 20 seconds to clear 40 JPEGs, 40 seconds for 19 raw files and 50 seconds for 19 raw + JPEG files, before full shooting performance is regained. Images can be captured on either SD or Memory Stick Pro Duo cards, with twin ports to hold them.
White balance and Colour
As I have come to expect from Sony’s Alpha cameras, images taken using the standard colour mode are bright and punchy, without overdoing it. In sunny conditions, for example, there is no need to use the vibrant colour setting. Further colour modes can be accessed via the function menu and manually fine-tuned. I did notice some colour fringing around the edges of tree branches against a bright sky in a couple of my images.
Auto white balance throws no curveballs. In natural light it performs fine, but as with most AWB systems it produces results that are too warm under tungsten light. The tungsten setting almost goes too far the other way, producing rather clinical, cool results, although this can be fine-tuned by ±3.
Metering
Evaluative metering produces pleasing results in a variety of situations
A 1,200-zone evaluative metering system can be found in all four new Sony models. The evaluative setting on the Alpha 580 does a good job in bright and contrasty light, and I found it limited the need to opt for spot metering.
Scenes with bright blue skies tended to be underexposed by 1⁄3EV, which is not a problem. Any situations that throw the metering can be addressed speedily by the handy placement and quick function of the exposure-compensation button.
Autofocus
As mentioned, the Alpha 580 features a new 15-point AF system, with three cross-type points. This is the same system as that used in Sony’s SLT models and, as with those cameras, the AF has been improved.
There is the choice between contrast- or phase-detection AF in focus check live view. During continuous shooting and for moving subjects, the AF is most effective for objects centrally placed in the frame.
Noise, Resolution and Sensitivity
The 16.2-million-pixel sensor records images with good detail and maximum file sizes of 4912×3264 pixels, which is good enough for A3-sized prints. Luminance noise is noticeable at ISO 800, although images at up to ISO 1600 are usable. The highest sensitivity of ISO 12,800 can be expanded to ISO 25,600 using the multi-frame noise-reduction mode. In this mode the processing time is roughly two seconds to combine the multiple images into one low-noise image.
Resolution detail is impressive. In JPEG files it reaches up to 26 at ISO 100 and 24 at ISO 200-1600 on our charts. Raw files reach 26 up to ISO 400, with a minor drop to 24 at ISO 1600, so it’s worth shooting raw files for best results. Images shot at ISO 25,600 in multi-frame noise-reduction mode are noisy and show less contrast, but resolved detail reaches an impressive 18 on our charts.
Resolution charts: These images show 72ppi (100% on a computer screen) sections of images of a resolution chart, captured using the kit lens set to 50mm (75mm equivalent). We show the section of the resolution chart where the camera starts to fail to reproduce the lines separately. The higher the number visible in these images, the better the camera’s detail resolution at the specified sensitivity setting.
Dynamic range
As is the case with the Alpha 55, the Alpha 580 has a solid dynamic range of 11-12EV. For any situations where the dynamic range is tested beyond its capabilities, the D-range button accesses HDR and dynamic range optimiser (DRO) modes to help fill in the lost detail and boost dynamic range.
The auto HDR mode has been optimised, although at times I find it removes some of the punch found with a regular image, and has a tendency to do the same to the DRO by lightening the darker shadow areas too much. That said, I had a lot of fun using this mode. The dynamic-range optimiser is handy as its single-frame capture can be used in scenes with movement.
LCD, Viewfinder and Video
There is no change to the folding LCD screen from that of the Alpha 550. The newer Alpha 580 features a 921,000-dot resolution screen that displays crisp detail and a bright output. The two-hinge folding screen is solid and built to last, and feels more durable than the Alpha 55’s single-hinge swivel screen, which is more susceptible to snapping off. That said, the two-hinge version is less flexible, with the folding action restricted to landscape-format photographs only.
The inclusion of an optical viewfinder is likely to please some ‘traditionalists’, but in reality I can only describe its performance as adequate. Viewing is a little dark and you really have to press your eye in close to see the image properly.
I found myself using live view as a preference, which is more intuitive as changes to exposure can be seen as they occur and the screen can be angled. Focus check live view is handy, but I have seen other systems that use a blow-up of the focus area when in manual-focus mode, which is a quicker method.
Sony developed its electronic viewfinder no end for the Alpha 55 SLT model, making it possible to access both menus and the scene through the eyehole, and it would not come as a surprise if this is the direction the company turns to more widely in the future.
For the first time, Sony has introduced Full 1080i HD video into its Alpha DSLR range. Image quality is crisp, but continuous focusing is not possible during shooting, unlike with the Alpha 55.
However, I filmed a video of around 20 minutes in length on the Alpha 580 and it showed no signs of overheating, whereas Sony’s SLT models have suffered from this problem and shut down after less than 15 minutes.
Our Verdict
It is easy to see why the Alpha 580 slipped under the radar while the Alpha 55 grabbed most of the attention. While in reality the key functions are all much alike, the Alpha 55 edges the Alpha 580 on more counts. The Alpha 55 is smaller, lighter, offers a faster frame rate and its SLT technology boasts quicker AF.
In its own right, the Alpha 580 is likely to please amateur photographers. It produces good-quality images, gives easy access to handy shooting modes and its higher resolution alone just about merits the extra money over the lesser Alpha 560. It is unfortunate for the Alpha 580 that with four Sony cameras similarly priced and specified, it is more likely to be the one deemed to be an excess.
