Sigmas 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. The diagonal fisheye is the most popular kind of fisheye and are often used by wedding photographers who want to give an “artistic” looks to images, by underwater photographers who want to take in the maximum field of view possible and by scenic photographers.A focusing distance of 5.9 inches and a magnification ratio of 1 to 3.8 allows the photographer to have fun with placement of subjects extremely near to the camera with distorted backgrounds. In the hands of an artist this lens can produce memorable, eye-catching images.