Canon 5d2, if you buy a fisheye lens, what should I shoot? What kind of fisheye lens should I buy? What is the cost performance?

The breadth of viewing angle and unique deformation are the biggest characteristics of fisheye lens.

Canon's wide angle is in lens EF 15mm f/2.8 fisheye.

Fisheye lens is classified as a super wide-angle lens, which not only has a large viewing angle, but also has the imaging characteristics that all parts except the center of the picture are greatly distorted. Its name comes from the phenomenon that fish in the water look out because of the refractive index of water, which leads to the round scenery on the water surface. The viewing angle of fisheye lens is usually close to 180 degrees. However, some lenses that can distort the part outside the center are also called fisheye lenses. In addition to the lens like EF 15mm f/2.8 fisheye lens (diagonal fisheye lens) which can make full use of the area of the image sensor, there is also a lens (circumferential fisheye lens) which can perform circular imaging in the picture. The diagonal fisheye lens has little deformation when shooting the foreground horizontally, and the effect is similar to that of a super wide-angle lens.

EF 15mm f/2.8 fisheye lens is the only fisheye lens in EF series with more than 60 lenses. It not only has the charm of super wide angle, but also has the strong deformation effect of radiating to the periphery, attracting many photographers.

Fisheye lenses are used to photograph landscapes and buildings. The photos taken by the fisheye lens are a little disguised, mainly to highlight the architecture and scenery.

The effect is still very good, and the fisheye lens has another function, which is to introduce contrast effect.

Generally, a good fisheye lens works well, and the photos taken by the fisheye lens feel the same as those taken by the super wide-angle lens, but the effect of the fisheye lens is not as good as that of the super wide-angle lens.