The Sony Alpha a58 DSLR is a compact DSLR camera that blends high imaging performance with a host of intelligent and intuitive features to help achieve optimal results for both still and moving imagery. The a58 houses a 20.1 megapixel APS-C-sized Exmor HD APS CMOS sensor and BIONZ image processor, which work together to produce clear, detailed imagery with impressive low-light sensitivity to ISO 16000 and fast performance that enables up to 5fps full-resolution continuous shooting. The processor and sensor combination are also significantly benefited by the unique Translucent Mirror Technology, which effectively directs light to both the image sensor and focus sensor simultaneously. This enables the 15-point AF system to work continuously even while recording video and photographing in a continuous shooting mode. In regard to video, full HD 1920 x 1080 video is supported at up to 60i or 24p, in the AVCHD version 2.0 format. The Internet-friendly MP4 format is also available when recording 1440 x 1080/30p movies for a more streamlined and efficient workflow.
The Translucent Mirror Technology also provides two means for image compositions, playback, and menu navigation: an electronic viewfinder and a rear LCD monitor. The SVGA Tru-Finder OLED EVF has a 1,440k-dot resolution to permit crisp live view monitoring of subjects and also allows you to preview the effects of camera settings while using an eye-level viewfinder. The rear 2.7" 460.8k-dot Clear Photo LCD monitor features a tilting design to greatly benefit working from both high and low angles, and the larger size is well-suited for image review.
For refining the overall look and appearance of imagery, an array of imaging features are incorporated into the a58 that allow you to both achieve optimal exposure results as well as apply creative effects. Auto HDR works to extend the dynamic range of a single exposure by combining three separate exposures-one over, one neutral, and one under-to garner the greatest tonal detail within a single frame. Multi Frame NR and Hand-held Twilight both work to enable hand-held shooting capabilities and noise reduction processes to aid shooting in dimly-lit conditions. When working with portraiture and still lifes, Auto Object Framing and Auto Portrait Framing work to create aesthetically pleasing compositions, based on the rule of thirds, automatically from original images. These modes utilize a system of intelligent detection and exposure methods to crop and enhance the look of imagery to create a new image that is both compositionally and tonally balanced in addition to the original image taken.
Also included with the a58 digital camera is the Sony DT 18-55mm f/3.5-5.6 SAM II lens, which provides a 35mm-equivalent focal length range of 27-82.5mm to provide from wide-angle to portrait-length perspectives. This lens features the SAM (Smooth Autofocus Motor) to offer quick and quiet performance that facilitates video recording and subject tracking. In regard to the lens construction, two aspherical elements and one ED (extra-low dispersion) glass element are incorporated to help reduce chromatic aberration throughout the zoom range while also helping to produce sharper imagery.
- 20.1MP Exmor HD APS CMOS Sensor and BIONZ Image Processor
- The 20.1MP APS-C-sized Exmor HD CMOS sensor produces high resolution imagery that exhibits notable low-light sensitivity to ISO 16000 with advanced noise reduction technologies. The BIONZ image processer also contributes to a high image quality and also provides enhanced speed and performance throughout the camera system, including a fast full-resolution continuous shooting rate of 5fps.
- Translucent Mirror Technology
- Translucent Mirror Technology is a unique design that enables the mirror to continuously direct light to both image and autofocus sensors to provide continuous phase- and contrast-detection focusing for quick and precise performance. The additional speed afforded to the camera by eliminating the need for a swinging mirror benefits many shooting features including the fast continuous shooting rate, continuous focusing when shooting movies and working in continuous shooting modes, and also allows for the use of a high resolution electronic viewfinder for eye-level live view monitoring.
- 15-Point Continuous Autofocus
- Utilizing the Translucent Mirror Technology, the autofocus system is able to continuously monitor the image frame and alter the autofocus quickly and responsively. This continuous focusing is especially useful when critical focus is required during video recording or when shooting in continuous modes. It uses 15 points, including three cross-type sensors, for a great deal of accuracy and speed when determining focus placement. The focusing system also works in collaboration with subject recognition technologies to provide enhanced focus tracking that can lock onto subjects and maintain focus even when the subject is moving within the frame.
- Sony DT 18-55mm f/3.5-5.6 SAM II Lens
- The included 18-55mm f/3.5-5.6 lens has a 35mm-equivalent focal length range of 27-82.5mm and features a portable design that makes it ideal for use in a wide variety of shooting situations. The integrated SAM (Smooth Autofocus Motor) provides quiet, quick, and precise focusing that well-suits video applications and tracking of moving subjects. Additionally, this lens features a refined rear element shade that helps to minimize internal surface reflections and prevent flare and ghosting in order to produce clear, contrast-rich imagery.
- OLED EVF and Tilting LCD Monitor
For live view monitoring, image review and playback, and menu navigation two distinct viewing options are available: a high-resolution electronic viewfinder or a large rear LCD monitor.
- The SVGA Tru-Finder OLED EVF features a bright and sharp 1,440k-dot resolution and provides 100% frame coverage for complete compositional accuracy. The finder has adjustable magnification and eye-point settings for more comfortable viewing possibilities and the eye-level viewing position can also serve as an additional point of contact between oneself and the camera for greater stability when shooting with longer lenses and in low-light conditions.
- The rear 2.7" 460.8k-dot Clear Photo LCD monitor provides a larger medium for viewing and composing imagery. It features a tilting design that is able to turn 135° upward and 55° downward to provide easier viewing when working from high and low angles.
- Full HD Video Recording
- Full HD 1920 x 1080 video recording is supported in both 60i and 24p frame rates in the high-quality AVCHD version 2.0 format. The Translucent Mirror Technology enables both full-time live view monitoring and continuous autofocus while recording for greater precision and ensured sharpness. Additionally, recording is also possible at 1080/30p in the MP4 format for a more streamlined workflow when shooting for web purposes.
- SteadyShot INSIDE Image Stabilization
- Sony's SteadyShot INSIDE is in-camera, sensor-shift type image stabilization that helps to reduce the appearance of camera shake up to the equivalent of 2-4.5 shutter speed steps; resulting in sharper, clearer imagery. Since the image stabilization system is housed within the camera body, any compatible A-mount lens can be used in conjunction with the a58 to receive image stabilization benefits.
- Auto Object and Portrait Framing
- Auto Portrait Framing and Auto Object Framing modes automatically create compositions revolving around your portrait and still life subjects and aesthetically crop your imagery based on the rule of thirds, where the subject is located within the frame, exposure on your subject, and, in the case of portraiture, the direction he or she is looking. Face Detection, Smile Shutter, and Face Recognition modes are all used in conjunction with Auto Portrait Framing for creating effective portraiture in a highly efficient manner. iAuto and By Pixel Super Resolution technologies are employed in both modes to render cropped images with full detail and clarity that also exhibit optimal exposure balance that is dependent on the newly-created composition. When working in either mode, the cropped image is saved in addition to the original, unedited photo.
- Auto HDR
- When this mode is selected, three separate bracketed exposures are made at a time and then automatically composited into a single file. This resulting file represents a longer range of tones in highlights, mid-tones, and shadows than is possible in a single exposure. Unlike traditional high dynamic range capture, this mode does not require the use of a tripod and simplifies the entire process into a simple, in-camera function.
- Multi Frame NR and Hand-held Twilight
- Similar in theory to an HDR image, Multi Frame NR and Hand-held Twilight feature a noise reduction technology that automatically combines six different images into one file for a reduction in noise up to two ISO stops (to an equivalent of ISO 25600). These modes also provide you with the ability to make handheld exposures with minimal image blur due to the fact that six individual exposures are being made at a faster shutter speeds compared to one long exposure.
- Picture Effects
- A variety of picture effects are supported for in-camera image-processing and creative applications. These effects include Posterization (Color and Black & White), Pop Color, Retro Photo, Partial Color (R, G, B, Y), High Contrast Monochrome, Toy Camera, Soft High-Key, Soft Focus, HDR Painting, Rich-Tone Monochrome, and Miniature.