One of the nicest things about high-specification Sigma lenses is that they come with a padded pouch, instantly suggesting that the manufacturer feels the lens is worth protecting. Sigma’s 50mm f/1.4 is no exception, boasting an enormous front element and a 77mm filter thread.

The lens tips the scales just over 0.5kg, which is almost twice the norm for an f/1.4 lens and closer to what might be expected for an f/1.2. In fact Sigma’s lens looks a lot as if it ought to have the extra half-stop but its price is not far above the f/1.4 average. Though its size and mass might deter some, neither of those factors has been allowed to reduce its Design score in this review.

The manual focus ring is comfortably wide and nicely located to the fore, offering the ability to apply manual adjustments in AF mode. Automatic focusing is quick, accurate and works internally, without disturbing the focus ring, but it could be a little quieter. Manual focusing, whether applied in AF mode or selected using the AF/MF slider, is on the heavy side. A depth-of-field window is provided and marked for use with f/8 and f/16.

Resolution testing produced the classic ‘aerofoil’ profile but with a steep ascent and decline that gives a very pronounced sweet-spot from f/2.8 to between f/5.6 and f/8, where the resolution stays above 0.4 cycles-per-pixel. This is a remarkable performance that is all the more impressive because it was sustained through multiple tests that included off-centre focusing.

There was very slight colour fringing at wide apertures but this went undetected in real-world pictures. The only enduring drawback after some time spent with this lens was its heavy manual focusing, which will probably be a minor consideration for most potential buyers.