Sigma's 15mm F2.8 EX DG Diagonal Fisheye is a diagonal fisheye which means the distorted scene is shown full frame within the camera's field of view. It allows photographers to shoot creative images by taking advantage of the acute perspectives that are invisible to the human eye.

I use this lens all the time. I love a good fisheye. The lens cap is easy to fall off but that may just be my model. Images look sharp and the color comes out nice. Focus is fast.

This lens is fine in itself, but not what I expected so returned.Sigma are a quality make and I have no complaint about their products.

I love shooting wide and for years I've loved the Nikon 10.5 fisheye on DX. So when I moved to FX I needed a new fisheye. The 10.5 works on FX but doesn't utilize the whole sensor. This Sigma is wonderful and gives me all the performance of the 10.5 in terms of sharpness, close focus, and color.

I was debating on getting either a wide angle lens or a fish eye but I am so glad I decided on this as it has more versatility and you can straighten the edges with the Hemi plugin if required.... Love it, it creates unusual perspectives at both weddings and landscapes.

Durable; Easily Interchangeable; Lightweight; Sharp Focus

I purchased this lens for my 5D MIII primarily for events, weddings, architecture, etc. I was hesitant to purchase an off brand lens, but Sigma has...

Great image quality; solid build quality

I was looking for an FX fisheye to replace my DX Nikon 10.5 Fish and it came down to this lens or the Nikon 16 f/2.8. The Nikon was over $200 more expensive and most reviews said this lens was slightly sharper. Both had the same 180 degree view somehow.

Very sharp; Easy to use; small and light weight

Tendency to overuse

Up until now I have been a Nikon purist - I wanted everything to be pure Nikon. I bought this lens because it was $300 cheaper than the Nikon 16mm Fisheye and it is every bit as good! I have not been disappointed yet!

Stellar performance for a fisheye lens. The lens is bright & fast. It's really fun to use. Simply set it in f/5.6 - f/8 and voila, all sharp images across the frame. I mostly use this lens for film (on my F75 or F90x). It brings great color saturation, sharpness & contrast across the images.

price; image quality; build quality

bad finishing (body) paint

Using this with my Sony NEX-3 in manual mode. Was looking for a very wide angle lens to replace the stock 18-50mm kit lense. An excellent lense! Crisp shots, smooth and easy to use.