Excerpt: This is very good glass (L) with great imagery. When using crop sensor, keep in mind that this is really only a 12.8mm, when set at 8mm. Though the image quality is quite good, keep in mind that you can pick up an inexpensive fisheye from Samyang at 1/4th the cost, if you can live with manual focus (8mm f/3.5). Samyang produces a quality fisheye, which I also own. Just beware the re-branders (Rokinon and others). Samyang is an actual manufacturer.
Pros: Consistent Output, Durable, Easily Interchangeable, Great glass, Rugged, Strong Construction, Usm Auto Focus
Summary: A little tricky to use...because of the fisheye you get vignetting, and will from any lens like this. It does an excellent job of producing a sharp image from 8 to 15, better than any alternative lens I have seen.
Summary: This is an excellent if odd lens. You cannot beat it for distortion (that's its thing) so if you want normality, this is NOT the lens for you. I have a specific application (panoramas) to which this lens is well suited. It works well with my full frame 5d mkii as well as smaller sensor Canon cameras. Lots of fringing (what do you expect when at 180 degrees field of view? Very useful for my purposes but a specialty item for sure.
Summary: This is a great ultra-wide angle lens which can add some new flavor to your portfolio. Be careful not to over do it. Also, keep in mind that some vignetting occurs when used with cropped sensors.
Pros: Consistent Output, Easily Interchangeable, Fast / accurate auto-focus
Excerpt: This is a must have lens for creative photography.<br />It worls as well on my full frame MKII as it does on my X1.6 60D.<br /><br />Truth is.... I may never remove it from the MKII as it gives me results better than I expected.<br /><br />As good as this lens performs and as well as the lens is built.... the lens cover seems to have been an afterthought by the designers.....<br />This is the only reason I cannot give this product a 5 star rating......
Pros: Durable, Fast / accurate auto-focus, Strong Construction