Sony A58 Review
Sony A58 Introduction
The Sony A58 is a new interchangeable lens camera that uses Sony's unique Translucent Mirror Technology to offer high-speed shooting and a smaller body size. The 20.1 megapixel A58 features 8fps burst shooting with new Lock-on Autofocus, full HD 25p video with control over exposure and continuous autofocusing, 15-point phase-detection autofocus system with 3 cross sensors, ISO range of 100-16000, a 2.7-inch tilting LCD screen, a high-resolution OLED Tru-Finder with 100% coverage, Sweep Panoramas, Auto HDR and Multi-frame Noise Reduction. The Sony A58 costs $600 in the US, and £450 in the UK for the body and the 18-55mm zoom lens or £600 in a twin-lens kit.
Ease of Use
The new Sony SLT-A58 is almost identical to the previous A57 model that it replaces. Measuring 128.6 x 95.5 x 77.7mm and weighing 492grams, the Sony A58 is the marginally smaller and lighter than the A57. Although it feels a little plasticky in-hand, the A58 is still a solid bit of kit with build quality that's on a par with rival DSLR cameras in the same price range, although we're disappointed to find that the A57's metal lens mount has been replaced with a less durable plastic version.
As with its predecessor, the A58 dispenses with an optical viewfinder in favour of an electronic version, and uses a fixed semi-translucent mirror instead of the moving non-translucent mirror of a DSLR. The translucency of the A58's mirror means that enough light can pass through it to the sensor to allow it to remain fixed in place at all times, with the ability to reflect some of the light onto a phase-detection auto-focus array that sits in the top of the A58 body. This combination means that the A58 can offer full-time DSLR-like focusing speeds, even during video recording, plus an excellent Live View system with 100% scene coverage and a fast continuous shooting rate of 8fps, whilst being physically smaller and lighter than a comparable DSLR.
The Sony A58 can shoot full-resolution 20.1 megapixel pictures at up to 8fps whilst maintaining continuous auto focus and auto exposure, a very fast fast rate for such an inexpensive camera. To achieve the full 8fps you need to set the exposure mode dial to the dedicated Tele-zoom Continuous Advance Priority AE shooting mode, which locks the exposure at the start of the sequence and uses the 1.4x tele-zoom function to record the center part of the image, resulting in a 5 megapixel photo. You can set the aperture and ISO speed by changing to AF-S or Manual focus mode, but you then lose the ability to refocus between frames. The A58 can shoot up to 16 Fine JPEGs at 8fps, but note that you can't shoot RAW files in this high-speed mode. Instead you have to use the slower 5fps option, which records a burst of either 7 Fine, 6 RAW or 5 RAW + Fine full-size 20 megapixel images.
The A58 features an adjustable rear 2.7-inch LCD which is hinged at the bottom and can be tilted down by 45 degrees and up by 90 degrees. Note that you can't tilt the screen out to the side or fold it against the back of the camera to protect it. The A58 has a clever eye level sensor that switches off the rear screen's info display as you bring your eye close to the OLED viewfinder, plus a facility that automatically flips the same display through 90° should you turn the camera on its side to shoot in portrait fashion.
One advantage that the Sony range still maintains over either Canon or Nikon is that the A58 features built-in sensor shift image stabilization, hence no need to spend extra on specialist lenses to help combat camera shake. On the Sony A58 light sensitivity stretches from ISO 100 all the way up to ISO 16000, with a quasi top speed of 25,600 achieved by taking and combining six frames at once (JPEG only). Sony's long-standing D-Range Optimizer and HDR functions help to even out tricky exposures, for example where a bright background would normally throw the foreground into deep shadow.
The A58 can record 1920 x 1080 pixel movies at either 60i/50i 24 Mbps, 60i/50i 17 Mbps, 25p/24p 24 Mbps or 25p/24p 17 Mbps in the AVCHD format, or 1440 x 1080 pixels at 30fps in the MPEG-4 format, useful as this format can currently be shared more easily. There's also a 640 x 480 VGA mode at 25fps, but no 720p mode. There's a limitation of up to 29 minutes, or 9 minutes if SteadyShot is turned on, for the AVCHD format, and a 2Gb file size for MP4 video. Stereo sound is recorded during video capture, and you can fit an optional external stereo microphone to further improve the quality. The HDMI port allows you to connect the A58 to a high-def TV set, but only if you purchase the optional HDMI mini-cable.
As with Live View, continuous phase-detection AF is possible whilst shooting movies on the A58, a distinct advantage over most DSLR cameras and fast enough to rival Compact System Cameras like the Panasonic Lumix GH series. It allows you to track fast-moving subjects without having to resort to manual focusing, ideal for users who are used to compacts that can auto-focus for both still and moving images. There are a few caveats - the focusing can be heard on the soundtrack, although using an external microphone gets around this, it sometimes struggles to keep up with the subject, and more notably the shallow depth of field that's inherent to a large-sensor camera produces noticeable and often unwanted "jumps" as the AF system locks onto different subjects in the frame.
In addition to continuous AF and manual, the selected AF Area can be changed within the frame to easily create the professional "rack focus" effect, where the focus moves between the background and foreground subjects. Also pleasing is the ability to change the shutter speed or aperture during recording with Program, Aperture-priority, Shutter-priority, and fully Manual recording modes all on offer. Exposure compensation, creative styles, picture effects, white balance, AF area, tracking auto-focus and metering mode all apply equally to stills and moving images too.
As you'd expect, it's also possible to focus manually with the Sony SLT-A58. 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 first introduced in the NEX-C3 compact system camera. Peaking is a feature that provides a level of hand-holding for manual focus users. When turned on to one of the three levels (low, mid, high), this essentially draws a coloured line (red, white or yellow) around the areas of highest contrast in the image when you're manually focusing the camera. Used in conjunction with the magnified focus assist, this makes it a cinch to focus accurately on a specific part of the subject, something that the majority of digital cameras have struggled with. It can even be used in the movie mode, again providing a real boon to your creativity.
The new Auto Object Framing mode builds on the previous generation Auto Portrait Framing mode by using face detection, By Pixel Super Resolution technology and the rule of thirds to automatically take better pictures of still lifes, moving subjects and macro close-ups. Sony's catchily named Pixel Super Resolution Technology ensures that the resulting image is still a full 20 megapixels in size, and the original uncropped image is also saved for easy comparison.
|Front||Tilting LCD Screen|
From the front the Sony A58 looks unthreatening to the novice DSLR user. Apart from a familiar ridge housing the pop-up flash above the Alpha lens mount, its most distinguishing feature is the traditional handgrip complete with leather-look rubberized covering that extends around the side of the camera. It's easy to fit three fingers around the handgrip and makes it straight-forward to hold the camera steady for shooting handheld. Built into the grip itself is a narrow sliver of a window for the remote sensor, should use of one be required as an optional extra.
At the top of this grip, but still at the front, is the camera's one and only control/command dial, situated beneath the main shutter release button and on/off switch, where it falls readily under the forefinger. In the absence of any top-mounted LCD window, users can twist this to rapidly scroll through screen menu options and folders, a task also achieved in slower, steadier fashion by tabbing through the same using the familiar four-way control pad at the rear, as well as adjust apertures and shutter speeds. A small Depth-of-field Preview button is located at the bottom-left of the lens mount.
Over at the other side of the lens mount we find a comfortably large button to release the lens, adjacent to which is a self-explanatory slider switch for alternating between auto and manual focus. Sony has subtly incorporated instances of its Alpha trademark 'cinnibar' (orange to the rest of us) colour on the camera, here only visible in the thin line encircling the lens surround. The Alpha mount also offers compatibility with A mount lenses from the Minolta and Konica Minolta range, Sony having bought up that company's expertise wholesale in 2005 to launch its own range.
The A58's top plate features the aforementioned shutter release button encircled by an on/off switch that visually apes the zoom levers found on some compact cameras. The shutter-release has a definite half-way point, with the focus points (a choice of 15) rapidly illuminating green in the viewfinder and a confirmation bleep signaling that focus and exposure has been determined and the user is free to go on and take the shot. With an imperceptible shutter delay, a full resolution JPEG is committed to memory in just over a second in single shot mode, a RAW file in three. The Clear Zoom function button, which is essentially a 2x digital zoom, and the Exposure Compensation buttons are handily positioned, although thankfully you can more usefully re-assign the Clear Zoom button to focus magnification.
Next on the Sony A58 we come to the Finder/LCD button alongside the pop-up flashgun and a large curved grille for the built-in stereo microphone. If choosing 'Finder' with the camera set to auto-focus, bringing your eye level with the viewfinder and sensor below will neatly prompt the camera to automatically focus on whatever it's aiming at (you can turn this feature off by disabling the Eye-Start AF menu option). Pressing the same button again switches to the LCD, automatically blanking out the viewfinder with the rear screen bursting into life instead. As expected the Sony's top plate also features a shoe for an optional accessory flash situated just above the electronic viewfinder, with a dedicated button to manually release the pop up flash situated just in front. The built-in flash can also trigger an optional wireless accessory flash.
Over at the far left of the A58's top plate is a shooting mode dial that's slightly sunk into the bodywork, thus helping to prevent the dial accidentally slipping from one setting to another when placing into or retrieving the camera from a bag. Arranged around this are 12 selectable options, running from full Auto and Auto+ to the creative quartet of Program, Aperture Priority, Shutter priority and Manual, plus dedicated modes for the 8fps continuous shooting, Panorama, Flash Off and a Scene option which includes pre-optimised scene modes for common subjects such as portraits, landscapes, close ups (macro), sports, sunset, night, night portraits and handheld twilight. The Auto+ mode goes even further than the standard Auto, automatically recognizing the correct scene mode and then taking advantage of the camera's high-speed shooting capabilities to shoot and combine up to six shots to produce images with greater dynamic range and lower image noise.
At the rear of the A58 we find a tiltable 2.7-inch LCD screen with a a fairly high resolution of 460K-dots, which is both smaller and lower-resolution than the previous A57 model. While the ability to tilt the screen is very welcome, placing the bracket at the bottom does make it impossible to attain the video-friendly side-on position that some other rival models offer, a real shame considering the A58's video capabilities, and you can't fold the screen against the back of the camera to protect it either.
Instead of the bulky optical viewfinder of a conventional DSLR, the Sony A58 has a smaller OLED electronic viewfinder. The electronic viewfinder on the A58 is better than a lot of other systems that we've used though. It has a high-contrast display, 0.88x magnification, 100% field of view, and a very high 1440k dot equivalent resolution, resulting in a display that rivals a more traditional optical viewfinder.
As the EVF is reading the same signal from the image sensor as the rear LCD screen, it can also display similar information, with a choice of five display modes. For example, you can view and operate the A58's Function Menu, giving a true preview of the scene in front of you and quick access to all the key camera settings while it's held up to your eye. The various icons used to represent the camera settings are clear and legible. The icing on the viewing cake is the clever built-in eye sensor, which automatically switches on the viewfinder when you look into it, then switches it off and turns on the LCD monitor when you look away.
The A58's EVF system also performs very well indoors in low light, typically the scourge of most EVFs which have to "gain-up" to produce a usable picture, resulting in a noticeably grainier picture. The A58 doesn't suffer from this unwanted effect at all, making the A58's electronic viewfinder the equal of and in many areas better than a DSLR's optical viewfinder, particularly those found on entry-level models which are typically dim and offer limited scene coverage. The truest testament to the A58 is that we almost exclusively used it by holding it up to eye-level, something that we wouldn't do unless the EVF was of sufficient quality.
|Memory Card Slot||Battery Compartment|
To the left of the electronic viewfinder is a button marked Menu. Press this and a number of shooting and set up folders appear on screen, with white text on a black background aiding visibility. The three shooting folders allow users to select image size, ratio and quality and - if JPEG (RAW and RAW+JPEG also available) - compression rates too, plus features like SteadyShot, long exposure and high ISO noise reduction - all in fact activated as a default, as is the likes of the eye start feature. The Movie folder contains the video quality and audio options, while the four Customise folders allow you to tweak the A58 to your way of working. Playback, Memory Card, Time and two further Setup folders allow the likes of the LCD brightness to be adjusted, the help guide to be turned on or off, plus user languages, folders and file numbering to be specified.
To the right of the viewfinder is a small wheel for dioptric adjustment that isn't too stiff and rigid. Just below and to the right of this is a welcome dedicated button for one-touch movie recording. A second marked AEL locks the exposure and also doubles up as a means of zooming into images and magnifying detail when in playback mode, while a third usefully sets the Exposure Compensation.
To the right of the A58's LCD screen is a Function ('Fn') button for those details that we'd expected to find amidst the menus but didn't. Here for example we find the Drive modes, Flash modes, along with Autofocus modes (a choice of single shot, auto or continuous), AF area (wide, spot or local), Object Tracking, Face Detection, Smile Shutter, ISO speed, Metering (multi segment, centre weighted or spot), Flash compensation, White Balance (including a custom setting), DRO/Auto HDR, plus Creative Styles and Picture Effects. Creative Styles are pre-optimised user selectable settings which run from the default of 'standard' through the self-explanatory vivid, portrait, landscape, sunset and black and white. For each of these creative options, contrast, saturation and sharpness can be individually adjusted. Picture Effects are a range of 11 creative effects that can be previewed on the LCD screen or electronic viewfinder and applied to both JPEG stills and movies.
Beneath the Function button we find a familiar four-way control pad. Ranged around this are settings for switching on or off the on-screen display, selecting from the white balance settings, Picture Effects (if in JPEG mode), and single shot / burst capture, self timer or bracketing options (three shots at 0.3EV intervals). At the centre is a 'AF' button that comes in particularly handy when scrutinizing the screen in Live View mode. Press this and, as with a press of the shutter release button, the camera will automatically and rapidly determine a point of focus for you. New to the A58 is the Lock-on AF function, which tracks the subject that is nearest to the centre of the screen and keeps it in sharp focus. Underneath these options is a playback button for the review of images and a self-evident trash can button for deleting images on the fly, which also doubles up as the Help menu button, essentially a mini in-camera user guide aimed at beginner users.
On the left of the A58 is an HDMI output in order to hook the camera up to an HD TV (the cable is once again an additional purchase) alongside the Multi Interface and external microphone connection, all protected by the same rubber flap, alongside the DC In port. Two partially recessed metal eyelets on either side of the body allow the supplied camera strap to be attached. On the bottom of the camera is a shared compartment for a choice of either SD or Memory Stick to save images to, a lithium-ion battery that supplies an impressive life-span of 690 images with the viewfinder or 700 images in Live View mode, plus a metal tripod socket that's in-line with the centre of the lens mount.