LensTip.com

Lens review

Sigma C 16 mm f/1.4 DC DN

22 January 2018
Maciej Latao

8. Vignetting

Let’s look at thumbnails below in order to assess the vignetting performance of the tested lens. JPEG files for this part we got with the help of the Olympus OM-D E-M5 Mark II.

Olympus E-M5II, f/1.4 Olympus E-M5II, f/2.0
Sigma C 16 mm f/1.4 DC DN - Vignetting Sigma C 16 mm f/1.4 DC DN - Vignetting


In this case the lens fares very well. You get chances to notice that aberration only at the maximum relative aperture where it is 24% (−0.80 EV). By f/2.0 the vignetting disappears practically completely, reaching just 7% (−0.21 EV).

- - - - - - - - - - - - - - - - - advertisement - - - - - - - - - - - - - - - - -

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

Results for RAW files are a bit higher – it’s a result of JEPG files correction and cropping – but the difference never exceeds 2%. It means also in the case of RAW files the vignetting is corrected very well indeed.

Of course the APS-C sensor is a greater challenge for the optics of the lens. Below we presents the results reached by the lens attached to the Sony A7R II in the APS-C mode.

Sony A7RII, APS-C, f/1.4 Sony A7RII, APS-C, f/2.0
Sigma C 16 mm f/1.4 DC DN - Vignetting Sigma C 16 mm f/1.4 DC DN - Vignetting
Sony A7RII, APS-C, f/2.8 Sony A7RII, APS-C, f/4.0
Sigma C 16 mm f/1.4 DC DN - Vignetting Sigma C 16 mm f/1.4 DC DN - Vignetting


In this case there are no differences between RAW and JPEG files. At the maximum relative aperture the brightness loss in the frame corners amounts to 43% (−1.62 EV). It’s a lot but, taking the parameters of the lens into account, the result is not bad. For example the more expensive Fujinon 1.4/16, a physically bigger device, had a result of 49%. Stopping down the aperture of the tested lens to f/2.0 allows you to decrease the vignetting to 22% (−0.73 EV). By f/2.8 that aberration is barely noticeable, reaching 12% (−0.36 EV). Further stopping down doesn’t have any measurable influence on vignetting levels.

With such a full frame body at our disposal as the Sony A7R II we could check the image circle of the tested Sigma and find out whether it is able to cover full frame. As thumbnails below show very clearly, it cannot cover such a big sensor and it lacks a lot to do so.

A7RII, FF, f/1.4 A7RII, FF, f/8.0
Sigma C 16 mm f/1.4 DC DN - Vignetting Sigma C 16 mm f/1.4 DC DN - Vignetting


Olympus O-MD E-M5II, JPEG, f/1.4
Sigma C 16 mm f/1.4 DC DN - Vignetting
Sony A7RII, APS-C, JPEG, f/1.4
Sigma C 16 mm f/1.4 DC DN - Vignetting