After quite a long period of doing very little (especially compared to main rival Sigma), Tamron has become a hive of activity, launching a steady stream of new or updated lenses over the last year.
What’s more, all have been pretty exceptional, especially the new ‘Generation 2’ designs which have included the f2.8-speed SP series 24-70mm and 70-200mm staples, and this exceptional 150-600mm telezoom. It packs a whole lot of optical fire-power into a comparatively compact lens which also isn’t excessively heavy. Hand-held shooting is feasible – especially with Tamron’s latest ‘Vibration Compensation’ optical stabilisation – as the lens is physically quite manageable and easy to carry around even all day. However, if you match with a monopod – which won’t compromise manoeuvrability – you’re also covered if you do want (or need) to use slower shutter speeds. The barrel is sealed against dust and moisture (and there’s a fluorine coating on the front element’s external surface) which is another plus for sports and wildlife photographers.
However, the icing on this already tasty cake is the optical performance. Maintaining uniformity of sharpness (i.e. from centre-to-corner) is always a challenge with 
zooms covering long tele-photo focal lengths, but Tamron has done an excellent job with its G2 150-600mm zoom. Likewise, both distortion and chromatic aberrations are well managed in most situations. Consequently, images look beautifully crisp, assisted by a nice amount of contrast.
Having the supertelephoto focal lengths from 400mm to 600mm available in a lens that’s only marginally bigger than a 70-200mm f2.8 zoom is a real luxury, but that the image quality is so good in this range is something extra special.
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