Review on Sigma 8mm f/3.5 EX DG Circular Fisheye Lens for Canon SLR Cameras: Wide-Angle Distortion at its Best by Sarah Richards

I am using this lens with a Canon EOS 6D (ex 5D) full frame camera and my previous fisheye lens was a Peleng 3.5/8mm. The optical quality of the Sigma is really excellent compared to the bearing. Most importantly, the resolution is much better than Bearing. It outperforms a 12MP (5D) sensor and looks very good on a 20MP (6D) sensor. This lens gave my spherical panoramas a huge boost in quality. I can even take pictures with the sun in the frame without any problems - there are almost no flares and loss of contrast. The black box around the image circle is truly black under most conditions. Old-school autofocus: slow, whirring, rotating ring. It worked fine on 5D, but on 6D it tends to back focus (beyond infinity) in landscape shots, I had to make a correction in the camera menu. Note, however, that AF performance is not important for Fisheye. I don't like the front cover: it's in 2 parts for some reason and is only held on the barrel by friction. I'd like a one-piece cover with some sort of thread or other more reliable connection. Overall a great product despite the relatively high price for a "toy" lens.