The Sigma 30mm F1.4 DN DC Contemporary was announced February 2016, and sits atop Sigma's line of DN mirrorless lenses, with a two-stop advantage over their previous 30mm F2.8 offering.

As a Micro Four Thirds lens, it is one of only several current autofocus F1.4 prime lenses available, with its closest competitor being the Panasonic Leica Summilux DG 25mm F1.4. While the Panasonic offers a field-of-view equivalent to a 'classic' 50mm lens, the Sigma ends up around 60mm. While that makes its focal length possibly a bit long for street shooting, it helps a little when it comes to portraiture and close-up work.

Let's see how the basic specifications between the Panasonic Leica 25 and Sigma 30 compare:

  Panasonic Leica Summilux DG 25mm F1.4 Sigma 30mm F1.4 DC DN | C
Price $598 $339
Image Stabilization No No
Max Aperture F1.4 F1.4
Minimum Aperture F16 F16
Aperture Ring No No
Diaphragm Blades 7 9
Minimum Focus 0.30 m (11.81) 0.30 m (11.81)
Maximum Magnification 0.11x 0.14x
Motor Type Micromotor Stepper motor
Full Time Manual Yes No
Weight 200 g (0.34 lb) 265 g (0.58 lb)
Dimensions (DxL) 63 mm (2.48)  X 55 mm (2.15) 65 mm (2.56) X 73 mm (2.87)
Sealing None None
Filter Thread 46mm 52mm

Regardless of where it sits in terms of focal length and usability, the Sigma enters the opposite of a crowded marketplace as an autofocus F1.4 Micro Four Thirds prime. It also gets the advantage of being the cheapest autofocus F1.4 Micro Four Thirds prime available, even undercutting the price of some F1.8 options as well. 

Thankfully, the Sigma doesn't feel entirely cheap. The barrel is well made with a satin black finish and ridges for grip when mounting or removing the lens. Sadly, the plastic hood feels a little inexpensive, and doesn't feel like it clicks in to position with much confidence. Build quality of the lens itself is on par with the Pana-Leica, with both having smooth, sturdy focus rings with rubberized ridged grips.

The extra bit of diameter and length on the Sigma make it a bit bulky and unbalanced when mounted to some of slimmer Micro Four Thirds cameras, like the Olympus PEN series, or the E-M5 II. When mounted to a larger SLR shaped body, like the GH4, the Sigma fits nicely.

We're assuming the extra size, relative to the Panasonic stems from it needing to be large enough to cover an APS-C sized sensor, in its E-mount incarnation.

Does the discounted price mean the Sigma comes with discount performance? Can it shake off past stigmas about third party lenses and go toe-to-toe with a lens touting one of the most revered names in the business? Let's take a closer look at the numbers.