Lens review

Panasonic G X VARIO 12-35 mm f/2.8 ASPH. P.O.I.S

18 March 2013
Arkadiusz Olech

8. Vignetting

The Olympus E-PL1, used by us in the test, doesn’t correct the vignetting so you can observe how that aberration looks on JPEG files.

Panasonic G X VARIO 12-35 mm f/2.8 ASPH. P.O.I.S - Vignetting

As you see the vignetting level here is very high, especially at both ends of the focal range. If you take into account the size of the detector you deal with here you can even say it is huge. At 12 mm focal length and the maximum relative aperture you must take into account the loss of as much as 49% of light (-1.93 EV). Stopping down the aperture to f/4.0 makes this aberration decrease to 28% (-0.94 EV). By f/5.6 and f/8.0 we get respectively 18% (−0.59 EV) and 14% (−0.44 EV). After further stopping down you can’t notice any measurable influence on the vignetting level.

Please Support Us

The coronavirus crisis has been adversely affecting many businesses and, sad but true, ours is not an exception. Despite that difficult situation we would like to preserve continuity and high quality of publications available on all our websites. Still, we are now aware it might be impossible without additional financial help. That's why we would like to ask all those who visit, read, and care about Optyczne.pl, LensTip.com i Allbinos.com for support - it's enough you send us a small sum of money via PayPal. If a lot people decide to support our websites we think we'll stand a chance and survive next months without any lasting harm. We count on your support and understanding, stay safe and be healthy.

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

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

The least vignetting problems you can spot in the middle of the focal range. At the maximum relative aperture the brightness loss in frame corners amounts to 24% (-0.79 EV) which is a moderate value. By f/4.0 the vignetting decreases to 15% (-0.46 EV) and by f/5.6 it becomes imperceptible (10%).

At 35 mm focal length you can observe the return to a high vignetting level. In the case of f/2.8 you must take into account the light fall-off as big as 42% (-1.56 EV). On stopping down the aperture to f/4.0 it’s reduced to 23% (-0.76 EV). The aberration becomes imperceptible by f/5.6 where it reaches just 10% (-0.29 EV).

One more thing is worth noticing as well. At the widest angle of view the lens gets a very high level of barrel distortion. It is corrected and images are cropped so the real field of view corresponds the declared one. It means, though, that the real focal length of the lens at its wider end is in reality shorter than 12 mm and the registered image features a larger angle of view than that stated in the specifications. Of course you can take advantage of that increased angle of view under the condition that you use independent software to develop your RAW file. There is also a price to pay – a larger field of view means higher vignetting. The image below shows clearly that, at the wide angle of view and maximum relative aperture the vignetting reaches a huge level of 70% (-3.56 EV). Such is a sad consequence of using a wider field of view than that stated in specifications.

Panasonic G X VARIO 12-35 mm f/2.8 ASPH. P.O.I.S - Vignetting

At other focal lengths the vignetting results you get for RAW and JPEG files differ in 2-3% at most. It is caused by the fact that at narrower angles of view the distortion is definitely lower and the cropping of images – reduced to minimum.

Panasonic G X VARIO 12-35 mm f/2.8 ASPH. P.O.I.S - Vignetting

Panasonic G X VARIO 12-35 mm f/2.8 ASPH. P.O.I.S - Vignetting

Panasonic G X VARIO 12-35 mm f/2.8 ASPH. P.O.I.S - Vignetting