Review by Klaus Schroiff, published April 2018

Introduction

As the name implies the lens is a member of the GM (G Master) class - thus Sony's highest grade lenses. Besides other aspects that also translates to top build quality based on a tightly assembled metal body. The zoom and focus rings operate smoothly. On the downside, the FE 16-35mm f/2.8 GM does extend slightly during zooming - or to be precise it does retract. The lens has its longest extension at the 16mm setting. Sony is still calling it an IF (internal focus) system because the size doesn't change during focusing - although that's nothing special anymore these days. Given its professional scope, it is, of course, weather-sealed. A fluorine front-element coating on the front element is supposed to repel dust and fluids. A small petal-shaped lens hood is part of the package.

The AF system is based on Sony's usual Direct Drive SSM. In fact, it doesn't have one but two of those units - probably because of the heavy lens groups. The system is silent and provides good albeit not exceedingly fast speed. Manual focusing works, as usual, by wire thus you are driving the AF motor by turning the focus ring. That's works nicely. Other than the usual AF/MF switch, you can also use a (reprogrammable) focus hold button for controlling the AF.