Lens review

Sigma C 30 mm f/1.4 DC DN

14 June 2016
Szymon Starczewski

4. Image resolution

The resolution test of the Sigma C 30 mm f/1.4 DC DN was based on RAW files from the Olympus E-PL1. In the case of that camera the highest results reached by the best fixed focal length lenses amount to about 80 lpmm (the record of 82.6 lpmm belongs to the Voigtlander 0.95/25 with the Olympus 1.8/75 close behind). The decency level is set near 44-45 lpmm.

Now let’s have a glance at a graph we show below and see how the tested lens compares in the frame centre and on its edge.

Sigma C 30 mm f/1.4 DC DN - Image resolution

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We have an impression that, at some point the Sigma optics specialists have joined a different league. Panasonic have asked Leica for help and Sony have been cooperating with Zeiss; there’s also Voigtlander whose lens held the resolution record in the Micro 4/3 system up to now. Still when Sigma enters the market they usually are able to offer lenses cheaper than those of their rivals but with a superior resolution. I hereby declare that the record resolution value doesn’t belong to the Voigtlander 0.95/25 anymore – our new champion is the Sigma with a result of 83.8 lpmm.

Are there any reservations concerning the performance of the Sigma 1.4/30 DN? With such a high resolution by f/2.8 and f/4.0 you could expect a tad better results at the maximum relative aperture. They are not bad mind you, but it’s worth reminding here that the Panaleica 1.4/25, even if suffering a resounding defeat in the duel with the Sigma when it comes to the maximum resolution value (it managed just 75 mm), at the maximum relative aperture fares by 5 lpmm better.

What’s interesting the situation is reversed on the edge of the frame. By f/1.4 and f/2.0 the Panaleica was simply weak while the Sigma even by f/1.4 reached decent results – a significant achievement. Near f/2.8 both lenses fared similarly and on further stopping down the Panaleica seemed to prevail albeit just slightly.

To sum up the Sigma C 30 mm f/1.4 DC DN has no weak points. Not only it is able to break resolution records but also it provides fully useful images across the frame at the maximum relative aperture. Still not impressed? Do try to browse our reviews and find another lens with similar angles of view which managed such a feat.

At the end of this chapter traditionally we present crops taken from photos of our resolution testing chart which were saved as JPEG files along with RAW files used of the analysis above.

Olympus E-PL1, JPEG, f/1.4
Sigma C 30 mm f/1.4 DC DN - Image resolution
Olympus E-PL1, JPEG, f/2.8
Sigma C 30 mm f/1.4 DC DN - Image resolution