Haptics and structure
The EF 14mm is a heavy, compact lens with metal body and plastic cover for his size. This design is common to all newer L lenses. The lens hood is integrated of metal and fixed. It is perfectly matched to the lens, but has only very limited protection. One charges somewhere, the front lens is virtually unprotected and in grave danger, for it includes almost flush with the lens hood on. A use of filters is not directly possible -there is indeed a kind of inner thread for the lens cap, but in that the lens front is flush with the lens hood could be the attachment of a filter with a makeshift solution, or any accessories that I now in moment just does not know, take place. To protect the lens is supplied in the form of a hood, a slip-on cover. Even this can not readily replace it with another one. At the latest at this very expensive lens should - like me who like the neglected - stop with the sloppiness of NOT mounted protective cover. Actually one should even put immediately after the photos the cover, because - the protection is otherwise "zero".
Autofocus
I did not think that the autofocus is so fail. Even at the edges of the measurement fields of my 5D Mark III there were no problems. I initially made a focus test in about 45 degree angle with a computer keyboard, when you see very quickly whether the focus sits as at maximum aperture adjacent keys are significantly blurred. I tested the auto focus when focusing distance of 20cm to 50cm at f 2.8 to 8.0 without any Fokushifts or other funny business. From 1m distance sharpness setting changes very rapidly at infinity.
Optical power
The lens is very sharp, especially in the center even at maximum aperture. Will you even in the extended center toward the edge a good sharpness, you should take pictures from Aperture 4.0.
What impresses me the minimum focusing distance of this lens. 20cm from the sensor means that you can put almost the lens hood on the object to be photographed. This can be mainly through the edge region conditionally create distorted shots (long snout dachshund, cat ears, for ages floral styles, etc.). However, that is not to be confused with a fisheye lens! Who speculates on an arched, strong distortion effect - Stay away! The lens has an overall very low for this focal length total distortion when the horizon is set correctly.
The diaphragm with six fins allows at f 2.8 a lovely "creamy" background blur - sure you can but that does not compare with lenses with 8 slats and a maximum aperture of 1.4 - but this is about a wide-angle lens, not a (portrait) Bokehwunder ,
From a Tokina 11-16mm DX lens, which I have previously also used at 16mm on full frame (and in front of it on a Canon EOS 7D), I have always been accustomed to be expected very strong chromatic aberrations out. The remains of at the EF 14mm. Even with snow on branches, which cries out for chromatic aberrations view is as good as anything seen in 100%.
An image stabilizer is not present, the one does not need at 14mm however.
Conclusion
For a crater in the Finance obtained an unrivaled super-wide-angle lens for Canon cameras with very good optical image quality. Of course you can also use the lens on Cropformat, where it has converted (form factor 1.6) is still very short 22.4 millimeters. However, it should be clear that this lovely little part should be necessarily operated on a full frame camera, because only here it comes into its own completely.
I would not hesitate to give 5 stars here, as also related to the price. Eben an excellent lens for a lot of money - for the professional, ambitious amateur photographers, or a thick wallet.
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Supplement - DECEMBER 17 2012:
Now I have yet found chromatic aberration in snow on branches that the overall image can miss a reddish tint, but compared to most other short focal lengths, keep this nevertheless greatly limited.
With regard to 22.4mm on Cropformat: Of course, not the focal length, but the framing of 14mm extended behaves on the smaller APS-C sensor as a 22.4mm lens on full-frame ...
