1 extra low dispersion, 1 low dispersion, 3 aspherical
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Confronto con Sony 28-70mm f/3,5-5,6 OSS e Sony 24-70mm f/2,8 GM
Although this lens doesn’t offer the same level of supreme corner sharpness that you get from Sony’s professional-grade standard zooms, it’s a truly excellent mid-range example. The extra stop you gain over the Sony FE 24-70mm f/4 ZA OSS Vario-Tessar Carl Zeiss T* makes it superior for low-light shooting and enables you to isolate subjects from their surroundings easily whilst producing very attractive blur behind.
Optically it is decent - for such a lens - albeit it comes with a couple of carefully placed compromises. At the wide-end of the zoom range, it is quite sharp across the image frame when stopped down to medium aperture settings whereas the center performance remains superb at 75mm [...] The corner performance isn't all that hot at large-aperture settings [..] Lateral CAs are fairly low at the image borders but intensify in the extreme corners.
If you are looking for a quality general purpose lens that has some unique magnification options, good image quality, and fast, quiet AF, you may have just found your new lens…particularly if you don’t want to break the bank to acquire it.
High vignetting and lower sharpness at the extreme corners of the frame, stopping down helps a bit and 90% of the frame looks excellent. Very useful macro features. Flare resistance can be critical with sun in the frame. Bokeh very distance dependant – the closer the focus the better. Images almost entirely free of chromatic aberrations. AF quite fast but not the fastest and quiet but not silent. It performs in line with expectations especially with price and size.