Canon A3300. What's the use of fisheye effect? Everything is distorted. Does it make people feel the horizon of fish in the water?

What is a fisheye lens and its function? Fisheye lens belongs to a special super wide-angle lens, and its viewing angle strives to reach or exceed the range that human eyes can see. Nevertheless, there is still a big difference, because the scenery we see in real life is regular and fixed, and the picture effect produced by fisheye lens is beyond this category. As we all know, the shorter the focal length, the greater the viewing angle, and the greater the viewing angle, and the stronger the deformation caused by the optical principle. In order to realize the super-large viewing angle of 180 degrees, the designers of fisheye lenses have to make sacrifices, that is, to allow this deformation (barrel distortion) to exist reasonably. In this way, except for the scene in the center of the picture, other scenes that should be horizontal or vertical have changed accordingly. It is this strong visual effect that provides an opportunity for imaginative and challenging photographers to show their personal creativity.

Application of fisheye lens;

1. Interesting prospects can have a strong visual impact;

2. The depth of field can range from a few centimeters to infinity;

3. Choose as few lines and faces as possible as the main body; Try to put the subject in the center of the picture when composing, which can minimize distortion;

4. On the contrary, choosing as many horizontal lines and easily recognizable scenes at the edge of the picture can maximize the distortion effect;

5. Pay attention to the edge of the viewfinder when taking a view to see if the photographer's hands, feet, camera belt or the photographer himself are taken into the lens, so as not to affect the artistic effect of the picture;

6. For most fisheye lenses, the common color filters can't be used.

Selection of fisheye lens

For photographers who want to use fisheye lenses, the first and most critical step is to decide what kind of fisheye lenses you want. There are three specifications to choose from: fisheye lens, fisheye lens additional lens and self-made device.

Only 35mm SLR cameras have real fisheye lenses. The focal length is about 8 mm, the image is completely round, and the viewing angle is 180 degrees; A few models can reach 220 degrees, mainly used for scientific photography.

Because fisheye lens is composed of many optical lenses, it needs precise molding and assembly, so its price is very expensive. Comparatively speaking, it is much cheaper to buy fish-eye glasses. This additional mirror has no focal length, but it can change the focal length of the original lens. For example, if an additional mirror with 0.4 times is mounted on a 50mm standard lens, its focal length will become 50× 0.42 mm If it is mounted on a 28mm wide-angle lens, the focal length change can be imagined. Special effects that only fisheye lenses can produce will appear in your viewfinder. Finally, try the self-made fisheye device: take a round hole in the spare lens cover, fix a household "cat's eye" mirror in it, and then cover this lens on a head to produce the effect of fisheye lens. This method doesn't cost much, and it can also make you enjoy a little fun after you start working.

15mm and 16mm fisheye lenses are common and suitable for 35mm SLR cameras. The 24mm, 30mm and 35mm fisheye lenses are suitable for Mamiya 645(6×4.5cm), Hasselblad (6×6cm) and Pantex 67(6×7cm) medium format SLR cameras respectively.