I decided to buy this lens for my FX format D750 instead of the 15mm Sigma fisheye, even though the Sigma is about one f-stop faster, because (a) an on-line review comparing the two lenses found that image quality was comparable--both produce very good images, especially at higher f-stop/smaller...

Very fast and precise automatic focus, sharp results also a really good construction and material.

Not to pile on, but maybe with repeated reviews on the lens cap falling off, Tamron will find a solution so I can protect my $500 glass! Otherwise, I love this lens.

I mainly use this lens for underwater photography. So far it has been great!

all what you need to capture a whaleshark swimming by

I love this fisheye, especially for underwater wide angle. I originally had the version with the lens hood, but sold it to purchase this version, which i can use with my 5D2. It's amazing the field of view on a ff camera! This lens is sharp, produces beautiful images.

I have used this lens for 1 year on a Nikon D5200 now. Great lensFor the D5200, it is strickly manual focus. I have recently upgraded my Nikon D5200 to a Nikon D7100; and low and behold, the auto-focusing feature works like a champ, it is lightnning fast.

Nice lens, good light and good quality.Just one problem, and it really stupid, I dont understand how the miss it. The lens cap has nothing to attach to the lens rather than a very soft magnetic, nos swithm neither a slot for a grip. You have to be care because it will fell down easily

works perfectly underwater, especially shooting large marine mammals as I do for a living. One day may try it topside and on a reef. But it is actually the preferred lens for many underwater professionals.

I bought this lens and went to Hawaii. I had so much fun shooting the flora of the state. Beautiful photos. I was nervous about buying a knock off lens but I'm not disappointed!