Sony 50mm f/1.8 DT ( SAL-50F18 ) on Sony NEX - Lab Test / Review
Lens Reviews -
Sony Alpha/NEX (APS-C)
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Review by Klaus Schroiff, published November 2010
Lens kindly provided by Renwei Chen!
Sony Alpha lenses can be connected to Sony NEX cameras using the Sony LA-EA1 adapter. Unlike e.g. a Leica M to Sony NEX adapter the LA-EA1 is smarter - it provides full camera control over the aperture mechanism with all Alpha lenses as well as AF with Alpha lenses featuring either a SSM or SAM AF motor. Regarding the difference in size & scope it doesn't make too much sense to use e.g. a Sony 300mm f/2.8 SSM on a Sony NEX camera but there're a couple of interesting candidates and the Sony 50mm f/1.8 DT is probably near the top of that list.
The build quality of the lens is average at best. The lens barrel is completely made of plastic and that's including the lens mount. It uses a linear extension system for focusing - the, slightly wobbly, inner lens tube extends slightly during the process. The tiny focus ring at the lens front operates smoothly. It remains coupled to the AF motor in AF mode so it rotates during AF operations. However, the filter ring does not rotate.
Now most NEX users are probably interested in the AF experience on their NEX. Frankly, it's bad - really bad. We're using a test chart with high contrast test targets here and the camera was not able to lock on and the situation isn't any better with "real world" objects. That's certainly a major let down. Manual focusing is a bit delicate due to the tiny focus ring and the rather short focus path (~60 degrees).
|Equiv. focal length||75 mm (full format equivalent)|
|Equiv. aperture||f/2.7 (full format equivalent, in terms of depth-of-field)|
|Optical construction||6 elements in 5 groups inc. 1(???) ED element|
|Number of aperture blades||7 (rounded)|
|min. focus distance||0.34 m (max. magnification ratio 1:5)|
|Dimensions||70 x 45 mm|
|Filter size||49 mm (non-rotating)|