Conclusion

Weighing in at well over 1.5kg and sporting a huge 105mm front element, the Sigma 105mm F1.4 DG HSM is a monster of a lens, but thankfully it delivers in the image quality department. Sigma have gone all out to make this the ultimate lens for bokeh lovers, and you certainly won't be disappointed if that description fits you.

The Sigma 105mm F1.4 DG HSM is a tack-sharp lens, both in the centre and at the edges of the frame, with little evidence of chromatic aberrations and virtually no distortion. Vignetting at wide-open apertures is the only real optical issue of note, something that similarly fast lenses also suffer from, although stopping down to f/4 solves this problem altogether.

As with other recent Sigma lenses that we've reviewed, the build quality of the 105mm F1.4 DG HSM is fantastic, with the brass lens mount and sober all-black design adding to the high-quality feel. Sigma have also included a very good lens hood and padded case complete with strap, while the removable Arca Swiss tripod collar is a great idea considering how big and heavy the lens is.

Auto-focusing was fairly quick and quiet on the Canon EOS 5DS R that we tested the lens with, and manual focus over-ride at any time is a great feature, with the large and well-damped focusing ring proving a pleasure to use.

The main drawbacks of the Sigma 105mm F1.4 DG HSM lens are its sheer size - it's too heavy to hand-hold for long periods - and its price-tag of £1499.99 / $1599.99, which makes it the most expensive of Sigma's three portrait primes, the 85mm, 105mm and 135mm. It also lacks image stabilisation, although including that feature would only have made it even bigger!

Overall, though, Sigma have delivered another home run with the 105mm F1.4 DG HSM - it's simply a must-have lens if portraits are your main photographic focus.

Ratings (out of 5)
Design	4.5
Features	4.5
Ease-of-use	4.5
Image quality	5
Value for money	4