Review by Klaus Schroiff, published June 2007

Lens kindly provided by Tamron Europe!

Introduction

In absolute terms the Tamron is a fairly big lens but within its class it is actually comparatively compact and light-weight. Fortunately the weight reduction measurement don't seem to come at cost of build quality - it is obviously a pretty sturdy lens also thanks to a constant physical length regardless of the focus setting. The very broad, rubberized focus ring operates very smooth. An nice feature is FEC (Filter Effect Control), is a dedicated control ring to rotate the filter thread even with attached lens hood - a quite interesting and efficient approach.

The 180mm f/3.5 has a conventional AF micro-motor which is moderately noisy and very slow when focusing throughout the extensive focus range. This can happen quite frequently because Tamron did not implement a focus limiter - in the middle of focus nowhere there's a good chance that the AF focuses towards the wrong direction before hunting back again. If the focus is well off it makes sense to do a coarse manual pre-focusing prior of activating the AF. You change between AF and MF by pushing/pulling the focus ring so there's no need to fiddle around with the small AF/MF switch on the camera. A side effect of this focus clutch design is the decoupling of the focus ring from the AF gears so it does not rotate in AF mode.