Sony A850 DSLR Sony 28 75mm F2 8 SAM Recensione | 108 Dati a confronto

The DPReview evaluation of the Sony Alpha DSLR-A850 highlights the camera as a robust, "no-nonsense" tool that lowered the barrier to full-frame photography with its 24.6-megapixel CMOS sensor. Key advantages include a durable magnesium-alloy body, excellent in-body SteadyShot stabilization, intuitive ergonomics, and superb image quality, particularly regarding RAW dynamic range and metering. Conversely, the A850 features a smaller buffer resulting in a limited 3.0 fps burst rate, a 98% viewfinder coverage, and notable digital noise at higher ISO settings. Additionally, it lacks modern, high-end features such as video recording, live view, or a built-in flash, making it best suited for studio or landscape applications.

The Sony Alpha DSLR-A850 offers an affordable entry into full-frame photography by featuring a 24.6-megapixel Exmor CMOS sensor, which matches the size of traditional 35mm film. This massive sensor delivers outstanding image quality, accurate colour reproduction, minimal noise at low ISO settings, and incredible detail that allows photographers to crop deeply into images without losing sharpness. The camera is constructed with a rugged, retro-styled black plastic casing that weighs just under a kilo. It features an exceptionally bright eye-level optical pentaprism viewfinder with 98% coverage, dual memory-card slots for CompactFlash and Memory Stick Duo media, and a high-resolution 3-inch LCD screen. Additionally, it includes an in-camera SteadyShot image-stabilisation system that functions seamlessly with any attached lens, including Zeiss, Minolta, and Konica Minolta glass. Despite its stellar imaging performance and rapid processing speeds powered by dual Bionz processors, the A850 makes several notable sacrifices to maintain its lower price point. The most significant drawbacks include the total absence of a video recording mode and the lack of a live view feature on the LCD screen, which is strictly restricted to menu...

The Trusted Reviews evaluation of the Sony Alpha a850 praises it as a "tank-like" and rugged, stripped-down version of the flagship a900, offering 24.6-megapixel full-frame imaging with an intuitive layout, including dedicated switches for stabilization and quick-access buttons. The key advantage is the superior image quality and build, delivering professional results at a more accessible price point. Conversely, the review highlights notable limitations, including an awkwardly placed preview button and the absence of live view, movie modes, and a built-in flash. Performance is constrained by a slow 3fps continuous burst rate, and it lacks modern backlit sensor technology, making it a transitional, though robust, option in the full-frame market.

The Sony Alpha 850 is a full-frame DSLR featuring a 24.61-megapixel CMOS sensor that captures high-resolution images capable of producing massive 51x34cm prints. Built with a high-tensile aluminium chassis and magnesium alloy shell, this heavy machine is paired with an internal image stabiliser that offers up to 4 f-stops of anti-shake performance for the large full-frame sensor. For file management, the camera offers a compressed data format called cRAW, which significantly reduces the typical 37.4MB RAW file down to 25.1MB. Its ISO sensitivity spans from 100 to 6400, providing clean and noise-free pictures at ISO 800, though noise creeps in at ISO 1600 and becomes heavily apparent at the maximum setting. Performance-wise, the camera features a 9-point AF system with 10 focus assist points, but it has a relatively slow continuous shooting speed of just 3 frames per second.

However, the review details specific compromises made to achieve its lower price point, alongside some inherent technical limitations. To differentiate it from the more expensive A900 flagship model, Sony reduced the continuous burst shooting speed down to a modest 3 frames per second (fps) and restricted the optical glass pentaprism viewfinder to 98% coverage rather than 100%. Performance in low-light environments is a significant drawback; digital noise becomes noticeable starting at ISO 400 and becomes problematic at ISO 1600 and above, causing a noticeable loss in fine detail, sharpness, and color saturation. The camera also lacks modern conveniences like a true Live View mode, built-in pop-up flash, or video recording capabilities, and it suffers from a somewhat slow playback display speed. Finally, the mechanical shutter and oversized reflex mirror are notably loud, making this DSLR poorly suited for quiet environments like wedding ceremonies or skittish wildlife photography. If you plan to use this camera, what types of lenses do you already own, or are you primarily looking to shoot landscapes and studio portraits where lower ISO speeds can be maintained?

The Sony 28-75mm f/2.8 SAM (SAL-2875) is a highly affordable full-format standard zoom lens option that serves as a budget-conscious alternative to the more premium Zeiss ZA 24-70mm f/2.8. Optically, the lens performs beautifully from f/4 onwards, achieving its peak across-the-frame sharpness around f/8, with the added benefit of excellent distortion-free images near the 40mm focal length. It handles longitudinal chromatic aberrations (bokeh fringing) exceptionally well, exhibiting only marginal traces at f/2.8 that vanish entirely by f/4. Furthermore, it serves as a lighter, well-controlled everyday option for shooters who prioritize value and a fast, constant f/2.8 max aperture. However, the lens suffers from notable performance flaws, particularly at its maximum f/2.8 aperture where corner and border resolution is weak, contrast is low, and vignetting peaks heavily beyond 2EV at 28mm. Severe barrel distortion (~2.6%) is present at the wide 28mm end, shifting to a 1% pincushion distortion at 75mm. The out-of-focus blur (bokeh) is also highly imperfect, displaying an onion-like substructure, "cat's eye" distortion at the borders, and rough, smeared backgrounds in the extreme corners. Mechanically, its basic SAM autofocus...

Ken Rockwell’s review highlights the Sony 28-75mm f/2.8 A-mount lens as an affordable, lightweight "Made in Japan" standard zoom featuring remarkably low distortion across most of its range and a well-designed manual focus ring. However, the lens is noted for significant softness and sagittal coma flare in the corners at f/2.8, along with a lack of a depth-of-field scale and a standard, rather than exceptional, bokeh quality.

The Sony Alpha a850 is a durable, full-frame DSLR featuring a 24.6-megapixel Exmor CMOS sensor, dual BIONZ processors, and effective built-in image stabilisation. It offers a competitive, lower-cost entry point into high-resolution, studio-quality imaging, housed within a rugged magnesium alloy body with an intuitive control layout. However, the camera lacks modern innovations, omitting live view, video recording, and a built-in flash, while offering only 98% viewfinder coverage. Performance limitations include a 9-point autofocus system and a slow-clearing buffer that requires high-speed UDMA 6 cards, representing a less advanced option compared to the flagship a900.

The Sony 28-75mm f/2.8 SAM (SAL-2875) review highlights this full-format Alpha lens as a more budget-friendly, large-aperture standard zoom alternative sitting beneath the premium Zeiss ZA 24-70mm f/2.8 SSM. The reviewer notes that the lens is an open secret, sharing its optical design—comprising 16 elements in 14 groups with multiple low-dispersion, aspherical, and extra refractive elements—with the Tamron AF 28-75mm f/2.8 SP XR Di LD. On the positive side, it features quite smooth operation on both the zoom and focus rings, a minimum focusing distance of 0.38 meters, a non-rotating lens front that makes utilizing polarisers easy, and a built-in zoom lock at 28mm. Additionally, its integrated Smooth Autofocus Motor (SAM) provides quite good autofocus speed compared to old screw-driven alternatives. However, the review outlines several prominent drawbacks, particularly regarding its overall value and build quality. Its construction materials and finish are merely consumer grade and do not match its Zeiss cousin. Furthermore, it is priced at roughly double the cost of the optically identical Tamron counterpart, making the price tag seem bold given the few cosmetic and motor updates....

The Sony SAL 28-75mm f/2.8 SAM lens (originally a Tamron design) serves as an affordable, lightweight mid-range standard zoom alternative to premium lenses like the Sony GM series. When paired with an E-mount full-frame body via an LA-EA3 adapter, it builds a relatively compact 683-gram setup that balances well with in-body image stabilisation. Pros include exceptional sharpness in the center across the entire zoom range on sensors up to 42 megapixels, superb performance across the APS-C image area, an acceptable bokeh quality, and a close focusing distance of 38cm. Furthermore, its autofocus via the adapter initializes faster than some native stabilised zooms, provides smooth continuous tracking in video, and functions quietly. Conversely, the lens reveals notable optical and physical cons on full-frame cameras. A significant "cap shape" field curvature causes severe softening in the extremes and corners of full-frame landscape images at 28mm, and noticeable misty aberrations can mask the image when shot wide open. Ergonomically, the manual focus design is a major downside: the focus ring rotates during autofocus and is highly vulnerable to damage if blocked or forced....

The What Digital Camera review awards the Sony Alpha a850 an 87% score, characterizing it as a robust, high-resolution alternative to the flagship a900. Key strengths include the 24.6-megapixel full-frame sensor, effective SteadyShot image stabilization, and an Intelligent Preview mode for checking exposure on the 3-inch LCD. Conversely, the camera lacks live view, video recording, and a built-in flash, targeting strictly still photographers. Performance constraints include a slow 3fps burst rate, inconsistent auto white balance, and an ergonomically poor placement for the Intelligent Preview button.