Super lens with unbeatable value for money !!!

Looking for a little weitwinkligeren alternative for the Fujinon 18-55m, I'm on the Walimex 12mm f / 2.0 encountered. The alternatives of Zeiss and Fujifilm have interested me, but were not affordable for a student strapped purse.

EQUIPMENT / PROCESSING

Lens, manual, thinner lens pouch, lens hood everything in it. The content can ever nothing to be desired.
The processing of the lens is really absolutely great. Feels really robust, no wobbles or rattles. The aperture ring is tight pleasant, wrong settings by mistake is there hardly. The focus ring could run against something smooth, because that goes also somewhat taut.
The lens is slightly larger, as the Fujinon 35mm, but still very compact and lightweight. However, there is against the Fujinon 14mm and the 12mm Zeiss, despite the absence of an autofocus motor, no size advantage, but a wider aperture.
An indication of the depth of field does not exist and the distance scale one should not accept as accurate. With focus Peeking and the viewfinder is focused but anyway no problem. And if you focus on just before infinity, then everything is sharp from a distance of 2m.
Electrical contacts to the camera, there is not, so the set aperture value is not transferred to the camera. But I had no problems with it overall.

Optical power

In the center is the Walimex 12mm really sharp and absolutely on par with other lenses. At maximum aperture, it is hardly better than the 18-55mm, but already just dimmed the Walimex 12mm is much sharper. Still further dim brings in the center is not much, but the edges have reached their optimum only at about f / 5.6. However, the edge sharpness not quite keep up with the level in the center, but is still at a good level and about on par with the 18-55mm. According to some tests, the Fujinon 14mm should be better there, but overall the edge sharpness is absolutely fine. A few test images with 100% -Ausschnitten are in the gallery.
Distortion as I could not make out so well, but I have not really paid attention in my tests. In some more professional tests (eg on lenstip.com) the Walimex 12mm showed even lower distortion as the Zeiss.
Vignetting, there are at maximum aperture, but really only noticeable if one really pays attention. Otherwise my vignetting is not misbehaving.
But what I have noticed, are quite strong CA's. On the screen and in the corners are quite present, typically at high contrast edges. On the whole, the fall though hardly on because the camera software a little nachhilft, but if you want an image to print times slightly larger, you should eventually edit it before. Lightroom can the CA's remove quite well.

CONCLUSION

Overall, the Walimex 12mm f / 2.0 lens is an absolutely great. The Zeiss 12mm or 14mm Fujinon may in terms of edge sharpness and CA's somewhat better, but it also costs more than twice as much and have one f-stop less. For me it is the first manual lens and I have not regretted the purchase. On the manual focus you get used to quickly, even if you, like me, has previously always familiar to autofocus. So if an ultra wide-angle lens for its Fujifilm X or Sony, Samsung seeks, should look at the Walimex 12mm necessarily.
Overall I would give the lens, like the previous other reviewers, 4 stars because it does bring a few compromises with them. In the good price-performance ratio but it has clearly earned 5 stars.

>>> <<< Summary

Positives:
+ In the center starting at f / 2.8 really sharp
+ Favorable price for an ultra wide-angle
+ A step wider aperture, as the competition lenses
+ Very good workmanship
+ Compact and lightweight

Negatives:
- Focus on the screen, can not keep up with the level in the middle
- Something too many CA's on the screen
- No electric. Contacts for camera
- No depth of field scale and imprecise focus scale

EDIT:
Since the test images are displayed very small and blurry in the gallery, I have set the link to the pictures in full resolution in the comments.