LensTip.com

Lens review

Sigma C 56 mm f/1.4 DC DN

22 December 2018
Arkadiusz Olech

6. Distortion



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Images below prove that the constructors of the Sigma C 56 mm f/1.4 DC DN kind of ‘forgot’ that full frame fixed-focal portrait lenses should be distortion corrected as well. As a result the tested lens breaks a dishonourable distortion record as its level amounts to +3.43%, a value shared by both RAW and uncorrected JPEG files. I honestly don’t remember a higher distortion result being reached by a fixed-focal lens with similar angle of view in our tests.

The word ‘forgot’ was put in quotation marks deliberately. I really don’t think Sigma optics specialists might have forgotten to correct distortion or don’t know how to do it. In this case it was a conscious decision to give it up and let a camera software to do the job; it was connected to the fact that the C series priorities are small physical dimensions and an excellent price-performance ratio. With those two dominating your list, you have to sacrifice features that are a tad less important. So far the image quality on the edge of the frame and distortion have been less than perfect. Are there going to be even more unpleasant surprises? Read on and find out!

Sony A7R II, JPEG
Sigma C 56 mm f/1.4 DC DN - Distortion
Sony A7R II, RAW
Sigma C 56 mm f/1.4 DC DN - Distortion