Sony Alpha 58 (SLT-A58K) review

The Sony Alpha 58 (SLT-A58K) offers an upgraded OLED EVF and kit lens, but it isn't the top D-SLR in Sony's lineup.
Photo of Sony Alpha 58 (SLT-A58K)

The Sony Alpha 58 ($599.99 direct with 18-55mm lens) is the current entry-level D-SLR in the company’s catalog. The 20-megapixel camera offers a few modest upgrades over the previous-generation Alpha 57, including an OLED viewfinder, but takes a step backwards in terms of burst shooting speed. If you’re in the market for a D-SLR with an EVF, we think the Alpha 65 is a better buy, though it is a bit more money. Traditionalists who prefer an optical finder are better off with our Editors’ Choice, the Nikon D5200.

Design and Features
The Alpha 58 is pretty typical in size for an entry-level D-SLR. It measures just 3.9 by 5.1 by 3.1 inches (HWD) and weighs 1.3 pounds without a lens. The Canon EOS Rebel T5i is about the same size (3.9 by 5.2 by 3.1 inches), but a bit lighter at 1.1 pounds. Like other Sony D-SLRs, the viewfinder is an EVF rather than an optical design. The camera still has a mirror, but it’s semi-transparent and doesn’t move. Most of the light hits the image sensor, but some is directed down to a dedicated phase detect autofocus sensor. This provides a seamless transition between the EVF and the rear LCD, and fast, accurate focus for both stills and video.

The EVF is an OLED design with a 1,440k-dot resolution. It’s a step up in quality from the LCD found in the Alpha 57, but it’s not the equal of the 2,336k-dot OLED viewfinder that Sony packs into its Alpha 65 and Alpha 77 cameras. That EVF is noticeably sharper, giving you a better idea of what you’re shooting. The rear LCD on the Alpha 58 is a little lacking as well; it’s a 2.7-inch panel with a hinged design so that it can tilt up or down. The resolution is 460k-dots, which is only half that of others in this class like the Pentax K-50.

The small LCD does leave a bit of extra room on the body for controls. On the rear you’ll find buttons to record movies, activate exposure lock, and adjust exposure compensation. Below those, directly to the right of the LCD, you’ll find the Fn button, which lets you control shooting settings via an on-screen menu, and a four-way control pad with directional buttons to adjust the information displayed over the live view feed, change the drive mode and activate the self-timer, adjust white balance, and control color output. The center AF button enables tracking focus, and there are also the standard image playback and delete buttons. The latter doubles as an on-screen guide that contains tips for the best settings for different types of photos. The menu button is located above the LCD, to the left of the EVF’s eyecup.

Up top there’s a mode dial, which has a few additional options beyond the standard settings. There’s one for scene modes, which set the camera to correct settings to capture different types of photos, as well as a special telephoto crop extends the reach of your lens and increases the maximum burst shooting speed, but reduces photo resolution to 5 megapixels. To the right of the EVF are the power switch, shutter release, ISO control, a toggle to change between the rear LCD and EVF (there is an eye-sensor if you’d like that to be automatic), and a button marked Zoom. This enables Sony’s Clear Image Zoom (for JPG shots only), which lets you enable as much as 2x digital zoom to extend the reach of your lens; images are saved at the full 20-megapixel resolution when using this function.

There’s a single control dial on the front of the handgrip. Most cameras in this class only offer a single control dial (which changes function based on the mode you’re in). Of the sub-$1,000 D-SLRs, only the Pentax K-50 (and it’s non-weather-sealed sibling, the K-500) offer front and rear control dials. That’s a feature that comes in handy when shooting in manual mode, but is also useful in other situations, including shooting manual with automatic ISO so that you can control shutter speed and depth of field without having to worry about calculating exposure. The Alpha 58 does support that function; to adjust the shutter speed in manual mode you simply use the front dial, and if you hold down the exposure compensation button the front dial function changes to control aperture.

Performance and Conclusions
The Alpha 58 is a little slow to start and shoot. It requires about 2.8 seconds to do so. The shutter lag is very, very short, we clocked it at about 0.05 second, although the time to focus does increase to about 0.2-second if the camera needs to drive the included DT 18-55mm f/3.5-5.6 SAM II zoom lens. In low light, focus slows to about 1.5 seconds. The Canon T5i takes a little bit longer to confirm focus and fire in good light, about 0.2-second, but offers similar focus performance in dim light, about 1.4 seconds. That camera slows down a lot when you switch to live view, requiring about 0.8-second to focus in good light and 2.4 seconds in dim light; the Alpha 58 delivers the same performance regardless of your choice of EVF or rear LCD for composition. 

In terms of burst shooting, the Alpha 58 takes a step back from its predecessor. It can shoot full-resolution photos at 5 frames per second; Raw or Raw+JPG shooting is limited to 5 and 6 shots respectively, but it can keep that pace for up to 10 JPG shots. It takes about 8.5 seconds to write all of the Raw+JPG photos to a SanDisk 95MBps memory card; that shortens to 7.1 seconds for Raw, and 4.1 seconds for JPG. There’s a special mode on the dial that increases the burst rate to 7.3fps, but it narrows the field of view of your lens by a 2x factor, and reduces resolution to 5 megapixels. The camera can capture 25 images before slowing, with only 3.1 seconds required to clear its buffer to a memory card.

The older Alpha 57 is able to fire off 28 JPG or 22 Raw photos at 7.8 frames per second, and has a 12fps mode that captures 8-megapixel JPG photos with a 1.4x crop factor. The reason for the step back in performance is simplification of Sony’s D-SLR line. There used to be an Alpha 37 model that was positioned as the entry-level body; that camera is gone, and the Alpha 58 replaces both it and the Alpha 57. It’s clear that Sony has cut down the buffer size in order to create more separation between this camera and the next model up in the series, the Alpha 65.

I used Imatest to check the sharpness of the included kit lens. This version of the lens, the 18-55mm f/3.5-5.6 SAM II, is an upgraded version of the older DT 18-55mm f/3.5-5.6 SAM lens, which we didn’t like when we tested it with the Alpha 57. The new version of the lens is noticeably sharper, recording better than the 1,800 lines per picture height that we use to define a sharp image at its widest angle. But its performance dips as you zoom in; it notches a mere 1,615 lines at 35mm f/4.5, but improves to 1,939 lines when stopped down at f/5.6. Zooming to 55mm f/5.6 gets you 1,605 lines, but you can get a sharper photo by stopping down to f/8, where it manages 1,898 lines. Edge performance is weak throughout the zoom range, and there’s noticeable amount of barrel distortion, about 3.7 percent, at the 18mm setting. The lens is a better performer than its predecessor, but it’s still underperforming, even for a kit lens. The 18-55mm lenses that Canon and Nikon D-SLRs use are sharper, but produce similar distortion at the wide angle. You can change the lens on a D-SLR, of course; and Sony has a number of lenses in its lineup that are strong performers, older autofocus Minolta Maxxum lenses are compatible, and you can opt for a top-end zoom like the Sigma 18-35mm F1.8 DC HSM if you’re willing to spend some money.

Imatest also checks photos for noise, which can introduce grain and rob photos of sharpness as you increase its sensitivity to light. The Alpha 58 keeps JPG noise below 1.5 percent through ISO 3200, which will let you shoot in lower light, especially if you’re working with a lens that captures more light than the included zoom. Detail is good through that setting, and also acceptable at ISO 6400, where noise is about 1.8 percent. If you shoot in Raw you get excellent detail through ISO 6400, though images are quite grainy. Things get dicey in either format when you push the ISO to 12800; images there are noticeably noisy and detail is muddy. The 16-megapixel Pentax K-50 is one of the better SLRs we’ve seen in terms of high ISO performance, and delivers similar performance.

Video is recorded in AVCHD format at 1080i60 or 1080p24 quality, or in MP4 format at 1080p. The quality is excellent, and the camera focuses very quickly thanks to its full-time phase detect autofocus. There is a mic input if you’d like to use the camera for projects where sound quality is imperative, as well as micro HDMI and micro USB ports. There’s a DC power input, a rarity in cameras of this class, in case you’d like to use it in a studio setting and not worry about battery life. The memory card slot supports standard SD, SDHC, and SDXC memory cards, as well as Sony Memory Stick PRO Duo cards.

The Sony Alpha 58 is a good D-SLR, but it’s not the best that Sony has to offer. If you’re a fan of an electronic viewfinder and the benefits that full-time phase detection offers for video capture and live view, you’ll be happy to know that the Alpha 58′s EVF is better than that of its predecessor. But it’s not as good as the one in the next step up in the line, the Alpha 65. Nor does the Alpha 58 match its burst capture capabilities. If you can afford it, we recommend getting that; it’s available as a body only ($650), so you can choose your lens, or with the new SAM II kit zoom for around $800. That might stretch the budget, but we think that the better EVF, shot-to-shot performance, and integrated GPS that come with the Alpha 65 are worth it. If you’re not an EVF fan, none of the current crop of Sony SLRs will make you happy. Optical viewfinder fans should take a close look at the Pentax K-50 and our Editors’ Choice Nikon D5200; the K-50 has a best-in-class pentaprism finder, but struggles with video performance, and the D5200 is an excellent all-around performer.

Specifications
Dimensions 3.9 x 5.1 x 3.1 inches
Interface Ports Mic
GPS No
Megapixels 20 MP
Battery Type Supported Lithium Ion
Recycle time 0.2 seconds
LCD dots 460800
LCD size 2.7 inches
Touch Screen No
Media Format Secure Digital, Secure Digital High Capacity, Memory Stick Pro Duo, Secure Digital Extended Capacity
Maximum ISO 16000
Type D-SLR
Sensor Type CMOS
Optical Zoom 3 x
Boot time 2.8 seconds
35-mm Equivalent (Wide) 27 mm
Weight 1.3 lb
Lens Mount Sony A
Video Resolution 1080i, 1080p, 480p
Lines Per Picture Height 1912
LCD Aspect Ratio 4
Image Stabilization In-Body
35-mm Equivalent (Telephoto) 83 mm
Shutter Lag 0.05 seconds
Sensor Size APS-C (18 x 24mm) mm
EVF Resolution 1440000 dpi
Viewfinder Type EVF

Verdict
The Sony Alpha 58 (SLT-A58K) offers an upgraded OLED EVF and kit lens, but it isn't the top D-SLR in Sony's lineup.
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