Conclusion

The Sigma 50mm F1.4 DG HSM is a fast and tack-sharp lens, both in the centre and at the edges of the frame, with virutally no evidence of chromatic aberrations and very little distortion. Vignetting at wide-open apertures is the only real optical issue of note, something that other fast lenses also suffer from, and stopping down to F/4 solves this problem altogether.

The build quality is fantastic, with the brass lens mount and sober all-black design adding to the high-quality feel, and Sigma have also included a very good petal-shaped lens hood and padded case. Auto-focusing was acceptably quick on the Canon EOS 5D Mark III that we tested the lens with, and manual focus over-ride at any time is a great feature.

Even the price of the Sigma 50mm F1.4 DG HSM is attractive, given the outstanding bulid and image quality on offer. The only concessions that it makes are the lack of weather-sealing and image stabilisation, which given the size and weight of the lens can be something of an issue in certain situations. Even so, we can whole-heartedly recommend the new Sigma 50mm F1.4 DG HSM as a brilliant "fast 50" prime lens that delivers superb results. Essential!

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