The K&F Concept 14mm, for Canon, is love at second sight. The first impression was a bit annoying due to the manual setting, since I am now spoiled by the (expensive) AF lenses from Canon, and especially because the lens has no jumping aperture. As a result, you can no longer see anything in the viewfinder or on the monitor from aperture 8. In order to focus, it is now necessary to first set a small aperture, focus sharply here and then stop down again to the desired aperture setting. Focusing itself is relatively unproblematic, especially because when using such an ultra wide-angle lens you often work with the hyperfocal distance anyway. I was absolutely positively surprised that the aperture priority works on my Canon 5D II. The processing quality is ok. Plastic, but it doesn't look cheap or filigree at all. Of course you can't compare it to the 2000-3000 euro alternatives from Canon or Zeiss. And now the optical quality: it's awesome! Absolutely sharp, I didn't expect it for the price, but now comes the but. The distortion, it's pretty intense. Not so bad for landscape shots, but quite annoying for architectural photography. Lightroom 5 can help here, as it can fix this with just a few clicks. My Lightroom does not write that it recognizes the K&F Concept, but the distortion is corrected well. For perfect results in architectural photography, Dxo Optics Pro helps, which also recognizes the lens independently. All in all a good lens that clearly exceeded my expectations. If I were a professional and used it several times a day, I might go for the more expensive alternatives, but as an avid amateur photographer, I absolutely love it.