Consult the parameters and selection method of SLR lens (plus 100)

The lens consists of a fixed-focus lens (for example, 85mm) and a zoom lens (for example, 28mm-200mm), and now the zoom lens is common. From a professional point of view, fixed focus imaging is definitely good but inconvenient. Non-professionals rarely use fixed focus. I won't say much about this.

Generally speaking, the quality of a lens depends on whether the aperture is constant and the focal length is reasonable. For example, the aperture is F/4-5.6 (non-constant aperture), which is definitely not as good as F/2.8 (constant aperture). Constant aperture means that the aperture will not change when zooming. For example, if you use a 28mm-200mm F/4-5.6 lens, when the focal length of the lens is 28mm, the aperture is 4. When you push it to 200mm, the aperture will be automatically limited to 5.6. However, if you use a lens with F/2.8 (constant aperture), this problem will not occur. However, there are not many lenses with constant aperture, and the price is also very high, which is basically around 10000 (you can consider second-hand). Then the aperture size is also very important, because the aperture size determines the amount of light entering the camera and the shutter speed of the camera in the dark environment. For example, when taking pictures in a room at night, the shutter speed of a lens with an aperture of F/4-5.6 is definitely slower than that of F/2.8, and it is more prone to false shooting. Another point is that the rationality of focal length is the combination of lens zoom length. If you just like elementary photography, Canon's body can also be equipped with Longteng 18mm-300mm, and you can travel all over the world in one mirror, except that you can't shoot Chang 'e on the moon. If you are an enthusiast or a professional practitioner, I suggest you choose a lens with a small focal length, such as 12-24 24-70 70-200, because only in this way can a lens with a focal length have a constant aperture or a large aperture. Simply put, the thicker the aperture of the lens, the better, because the larger the aperture, the larger the aperture.

The function of the lens mainly depends on the focal length.

general idea

Fisheye 14mm big scene, dedicated for creation, very distorted, fish looks like things.

Ultra-wide-angle 16mm-28mm landscape photography, the scene and creation are somewhat distorted, and the picture coverage is wide.

Wide-angle 28mm-50mm scenery photography, scene, portrait location, small deformation of creative special effects, no deformation of 50 segments, wide picture coverage.

Medium focus 50mm-80mm landscape photography, scenes, portraits, large still life, dedicated to creation, covered with small pictures.

Telephoto 80mm-200mm portrait, still life, dedicated to creation, can shoot objects far away.

Super telephoto over 400mm sports photography, wildlife, special for creation, and the ratio of objects to be photographed is far away.

There are also special lenses, such as macro lenses, which mainly shoot small still lives such as insects, flowers and rings.

There is also a kind of lens with special function, which is specially used to take pictures of buildings with shift lens, but it is rarely used. Professionals take pictures with landline.

Canon's lens has many other parameters, such as image stabilization and optical glass. When choosing it, you don't have to care about these. It doesn't make much sense. I didn't consider these when I matched them. A good lens still depends on the focal length and aperture. As for other functions, they are secondary. Besides, generally good lenses cover those functions.

As for how to match the lens, it depends on what you do, if you plan to take portraits professionally.

Even people with a fixed focus of 85mm F/ 1.4 are the best, and 80-200mm F/2.8 is also possible. Two new models are around 10000, and the second-hand models are around 5000.

If you are a beginner, I suggest you get an EF28-200mm f/3.5-5.6 USM directly, and the price seems to be less than 3000. Now, if different brands of lenses are not recommended, Longteng's 18-300mm F/5.6-6.3 is your better choice. You can travel all over the world in one shot and help you install the focal length change of my lens as soon as possible. More importantly, it can still play a role after graduation, because many of my friends who often play photography are equipped with this head, and there is nothing important to do. It is still very easy to go out with this head and a fuselage.

If you are a beginner enthusiast, you can match two pan/tilt platforms of 24-70mmF/2.8 and 70-200mmF/2.8, and then gradually add the wide angle of EF 14mm f/2.8 fisheye 17-55mm f/2.8 when you are promoted to a super enthusiast, but they are all valuable.

If you are a die-hard fan, I suggest that you have 24-70mmF/2.8 and 70-200mmF/2.8, EF 14mm f/2.8 fisheye 17-55mm f/2.8 and wide-angle EF100-400 MMF/4. 50 fixed focus (standard) 85 fixed focus (portrait king) 180 fixed focus (macro), Longteng 10-300, what other lenses, like Tully's 800- 1600mm, and a Canon bayonet. This equipment is invincible. . . No matter shooting insects, elephants, races, diving, airplanes and cannons, you can shoot stars and the moon, haha. But I suggest you add three cameras, because it's too much trouble to take pictures with too many lenses, and you also have two tripods for your camera, haha!

I'm exhausted, hehe! Do you understand? If you really like photography, I recommend a book for you. I remember it was called New York Institute of Photography Course, which was very detailed. I bought it a few years ago 160. After reading it, I believe you are very proficient in photography, hehe!