What are the functions of fisheye, wide angle and macro respectively?

Fisheye lens is a kind of short focal length super wide-angle photographic lens with a focal length of about 6- 16 mm, and "Fisheye lens" is its common name. In order to make the lens reach the maximum photographic angle, the front lens of this kind of photographic lens protrudes to the front of the lens in a parabolic shape, which is quite similar to the fish's eyes, hence the name "fisheye lens".

The basic characteristics of a wide-angle lens are its large viewing angle and wide field of vision. The range of scenery observed from a certain viewpoint is much larger than that seen by human eyes at the same viewpoint; The depth of field is long, which can show a fairly clear range; It can emphasize the perspective effect of the picture, be good at exaggerating the foreground and express the sense of distance of the scene, which is conducive to enhancing the appeal of the picture.

Macro photographic lens refers to a special photographic lens that can be used for macro or close-up photography without installing close-up accessories such as close-up mirror, close-up collar and close-up track leather cavity. Macro camera lens is a kind of camera lens for shooting tiny objects or retaking small pictures. This kind of lens has quite high resolution, minimum distortion and aberration, high contrast and good color reproducibility.

The size of fisheye lens is very large. Take the fisheye lens for a 35mm single lens reflex camera as an example. The fisheye lens is installed on the body of a smaller 35mm single-lens reflex camera, which has a feeling of "big head (lens) and small body (body)", and the weight of the fisheye lens is not light (for example, the manual focusing fisheye lens of Nicol 6mm /F2.8 weighs 5,200g). 、

As mentioned above, the front lens of the fisheye lens has a large diameter and is thrown in front of the lens, so this lens cannot be equipped with a filter like a normal lens. Fisheye lenses usually use a built-in filter. According to the shooting needs, the photographer manipulates the filter conversion ring on the lens to convert the required filter into the shooting light path of the lens. The front lens of fisheye lens is a very important lens in the whole lens. Because it is thrown in front of the camera, the photographer should pay special attention not to collide with the camera when shooting (especially when shooting close to the subject).

In addition, when some old fisheye lenses are connected to a 35mm single-lens reflex camera, the back of the lens is deeply inserted into the camera body, and the mirror of the camera must be turned up and locked, and the pentaprism viewfinder of the camera will not be used, so it is necessary to set an additional viewfinder on the camera to take pictures.

Wide-angle range, covering a wide range of scenery. The so-called wide viewing angle range means that at the same viewing point (the distance from the subject is constant), the scene is viewed with wide-angle, standard and telephoto lenses with three different focal lengths. As a result, the former shoots more up, down, left and right scenes than the latter. When the photographer has no retreat, it is difficult to take a complete picture (such as taking a group photo) with a standard lens of 50 mm ), using a wide-angle lens can easily solve the problem. Furthermore, for example, shooting a vast Yuan Ye or a tall building in a city, perhaps only a part of the scenery can be photographed with a standard lens, which cannot show the breadth or height of the scenery. Shooting with a wide-angle lens can effectively show the open momentum of large scenes or majestic buildings.

Macro photographic lenses generally have two structures. One macro photography lens adopts the structure of built-in telescopic lens barrel, and the other adopts the structure of exchanging the front and rear positions of optical lens groups in the lens. The former, in ordinary photography, the photographer can focus normally only by turning the focus ring of the lens. If he wants to take a close shot, as long as the focus ring that has been rotated to the nearest focus position continues to rotate, he can move the entire optical system of the lens forward synchronously with the built-in lens barrel, thereby increasing the image distance and achieving the purpose of close shot. The latter obtains higher image magnification by changing the front and rear positions of the optical lens group in the lens, thus achieving the purpose of close-up.