Review by Klaus Schroiff, published December 2015

A few weeks back we reviewed this lens on the Sony A7R II. For obvious reasons we are reusing some portions in this APS-C format review again.

Introduction

Just to mention the origin of the "Sonnar" portion in the lens' name again - Sonnar is derived from the German word "Sonne" (sun) and is used for fast Zeiss lenses. Sonnars are using a reduced amount of elements for better contrast and flare compared to "Planars" although the latter are generally sharper (less aberrations). Now a maximum aperture of f/1.8 is not exceedingly fast for a 50/55mm lens but in the grand scheme of things it certainly is. Conventional 50mm f/1.8 lenses aren't overly expensive - in the DSLR world the pricing hovers around the 200 US$ mark - but mirrorless prime lenses are always more expensive and the Zeiss brand will has its share in a price tag of around 1000 US$/900 EUR. This will certainly cause headaches among some potential buyers. Whether the lens is worth this amount of money ... well ... we'll see.

The Sonnar is very small, light-weight lens. However, the low weight doesn't come at the cost of build quality which is pretty much exceptional. The outer barrel, the mount as well as the focus ring are made of metal whereas the inner frame for the optics is made of plastics. Everything is tightly assembled with no wobbling whatsoever. The focus ring operates smoothly and it's even slightly dampened. The lens also features a weather sealing. A deep petal-shaped lens hood is also part of the package.

The AF on the NEX 7 is generally not stunning (although not that much worse than on the A6000 which we also used for a while) but the Zeiss lens focuses reasonably fast on it. It is worth to mention that it wasn't a speed demon on the A7R II either. AF operations are essentially noiseless. Typical for E-mount lenses, focusing works "by-wire". The implementation is really good and allows very fine grained focusing.