How to take better photos with telephoto lens?

Compared with ordinary focal length lens, telephoto lens will make the image have larger magnification and narrower viewing angle. For a 35mm camera (or a digital SLR camera with Quan Huafu sensor), the focal length of the long focal length lens is 105mm. 120 67cm film camera, the commonly used focal length is 150mm, the focal length of 45 panorama camera is about 300 mm, and the sensors of most digital SLR cameras and portable digital cameras are smaller than 35mm film frames. You can compare the perspective of your lens with that of 35mm film lens. The ratio of a 22.5 15mm sensor is1.6; That is to say, the angle of view of the photos it takes will be the same as that taken by a 35mm film camera with a lens with a focal length of 1.6 times. For example, a 22.5 105mm sensor camera uses a 65mm focal length lens, and its viewing angle is the same as that of a 35mm film camera using a 105mm focal length lens.

When you don't want to get close to the subject, using a telephoto lens is a very good choice. Opposite the camera, although the photographer is not in the picture, it can still give people an immersive feeling. The telephoto lens makes it possible to shoot at a long distance. You can use it to shoot birds or other animals from a distance without disturbing them. The medium and long focal length lens is an excellent choice for portrait photography. When the camera is too close, most people will feel uncomfortable and their expressions in front of the camera will become unnatural. When the short-focus lens is too close to the subject, the part closest to the camera will be magnified and distorted, while placing the long-focus lens at a medium distance can avoid this distortion. In portrait photography, the twisted part is usually the nose

The telephoto lens has some disadvantages, and the longer the lens, the more obvious the disadvantages. Compared with lenses with normal focal length, telephoto lenses are usually heavier, larger and more expensive, especially telephoto lenses with large aperture. Because their depth of field is very small, they must be focused accurately. At the same time, it is more difficult to shoot with hand-held telephoto lenses, because they will amplify the jitter of the subject and the lens at the same time. For a medium telephoto lens, such as 105mm lens on a 35mm film camera, if the camera is hand-held, the shutter speed should be at least1125s. For an unstable 200mm lens, your shutter speed should be at least 1/ 250 seconds. Otherwise, the camera's jitter may cause the picture to be blurred. A tripod or other stand will be the best choice to prevent photos from blurring due to camera shake.

A telephoto lens has many advantages that can be used. Because the telephoto lens has a small depth of field, the subject can be made more prominent by defocusing the foreground or background. At the same time, the telephoto lens can shoot from an extraordinary angle, making the subject look closer.

Photographers usually refer to telephoto lenses as telephoto lenses or telescope heads, but not all telephoto lenses are actually designed according to telephoto lenses. The effective focal length of a real telephoto lens is strictly greater than the distance from the lens to the focal plane. This design makes the lens shorter and easier to carry. A telephoto extender or conveyor includes a selection element that can increase the effective focal length of any lens. It is connected between the lens and the camera body, and magnifies the image in the lens and projects it on the film. With these devices, the effective focal length of the lens will increase, but the light reaching the film will decrease. For example, a converter can double the focal length of the lens and at the same time make the lens lose two F-stop apertures.

A telephoto lens can often take a better portrait. A medium telephoto lens, such as an 85mm or 105mm lens (equivalent to 35mm), is at least 1.8m away from the subject (as shown in the lower left), and the portrait taken with a shorter lens is better than that taken with a closer lens (as shown in the lower right). Comparing the shape and size of the nose and chin of the same subject in two images, we will find the differences. When the photographer is too close, the part closest to the camera will appear too large and the size of the head will appear unnatural.

Athletes in sports events, such as these paddlers, have a certain distance from photographers. Photographers usually rely on telephoto lenses, such as the 500mm telephoto lens here, to make their movements more tense. Jones keeps the lens at a medium aperture so that he can use a higher shutter speed while still keeping the focus of the side-by-side ships.

The distance between the photographer and the subject compresses the sense of space in the picture.

Lens focal length-short focal length

Shooting from the same position, the short focal length lens has a larger viewing angle than the ordinary focal length lens and can shoot more scenes. When your body is blocked and you can't retreat (for example, blocked by the wall of a room), a short-focus lens (usually called a wide-angle lens) is very useful. It is as essential as a normal focal length lens.

Quan Huafu digital camera or 35mm film camera, the most commonly used short-focus lens is 28mm. Relatively speaking, the short-focus lens of a 6x7cm film camera is 55mm. For a 4×5 inch viewfinder, the equivalent short focal length lens is 90 mm. ..

A wide-angle lens has a considerable depth of field. The 24mm lens focuses on the subject 2 meters away, and the aperture is adjusted to f/8, which will be able to clearly shoot objects from 1.2 meters to infinity. Photographers often use a wide-angle lens moderately in the case of fast motion, such as a Quan Huafu digital camera or a 35mm film camera with a 35mm lens, and regard it as a normal focal length lens. They don't need to stop and refocus every time they press the shutter, because the image of this lens is clear enough. At the same time, there will not be too much distortion.

Photographs taken with a wide-angle lens can show real and obviously distorted effects. The distortion of the lens itself, such as curve distortion, is inherent, which is caused by the excessive bending or width of some components made of thick glass sheets, which are often used in wide-angle lenses. Although most distortions can be corrected by moderate viewing angle and speed, the wider and faster the lens, the more difficult it is to correct and the higher the cost. Some curve distortions (straight lines near the border edge will bend) can be corrected by software. If the lens is not distorted, the photo will be better.

SLR cameras need to use a special wide-angle lens called anti-focus lens to leave room for the mirror behind the lens to move. The distortion caused by this lens is more difficult to correct. Wide-angle lens with rangefinder-free camera or viewfinder camera usually has better shooting effect.

Wide-angle lenses can also show obvious perspective distortion, but this distortion is caused by the photographer's position, not the lens itself. Objects close to the lens (or your eyes) will appear larger than objects of the same size far away. Wide-angle lenses are often close to the subject, exaggerating the size relationship (as shown below). The solution to this problem is to learn to look at what the camera sees, reduce distortion or deliberately use it.

A wide-angle lens allows you to shoot at close range, such as in a child's bedroom. The child's feet are very close to the camera, which creates an unusual perspective relationship and creates a distorted and somewhat amazing scene.

Lanting used the super wide-angle lens on his 35mm camera to fuse the hopes of tourists who came to the same river beach by cruise ship 72 years later, and saved Ernest shackleton's Antarctic expedition which suffered heavy losses from here in 19 16. This black-and-white photo of Frank Hurley was preserved during his expedition. Lanting printed the negatives of Hurley's works, took them to the South Pole, and began to recall the story of shackleton.

The wide-angle lens is close to Hurley's photo, which makes it obviously enlarged, making the characters in the photo look almost as big as the people standing in front of the ship in the background.

Lens focal length-zoom lens

Zoom lenses are very popular because their focal length is an interval. For example, with a zoom lens of 24 ~ 105mm, you will immediately have a lens with focal lengths of 24mm, 28mm, 50mm, 85mm and 105mm, and any focal length in between. The lens elements in the zoom lens can be moved in correlation with each other, which can change the focal length and thus the size of the image.

It is very practical to change the focal length only by zooming instead of changing your lens and position. Some photographers only bring two lenses: a 24 ~ 80mm zoom lens and a slightly longer 80 ~ 200mm zoom lens. Zoom lens is very useful for accurate positioning of images, because cutting and enlarging photos after exposure will greatly reduce the quality of photos.

Zoom lens gives you different focal lengths. As shown in the figure below, the photographer took the photo on the left with the shortest focal length, the photo in the middle with the normal focal length and the photo on the right with the longest focal length. The photographer's position of these three photos remains unchanged.

Zoom lenses also have some limitations. Compared with fixed-focus lenses (sometimes called "basic lenses"), zoom lenses are slower, which means their maximum aperture is smaller. They are usually more expensive, heavier and have poor optical effects, but zoom lenses can usually be used as two or more fixed-focus lenses.

The zoom lens with the highest cost performance often has a moderate zoom range, such as 35mm ~ 105mm or 24mm~70mm. The larger the zoom range, the more disadvantages.

Some zoom lenses usually work best in full light because their maximum aperture is very small. The zoom lens used to keep the maximum aperture constant during zooming is complicated in design, so it is expensive. Most of the maximum aperture will decrease with the increase of focal length. For example, a zoom lens with a focal length of 28mm ~ 105mm has an aperture of f/4, and when the focal length becomes 105mm, its aperture is only f/5.6.

Tip: When using the zoom lens, please pay special attention to whether your shutter speed is fast enough to prevent the photo from becoming blurred due to camera shake. When shooting in hand, the shutter speed of the 28mm lens is about 1/30 seconds, but when the focal length of your zoom lens exceeds 100mm, your shutter speed should be controlled at least above1125 seconds unless you have a tripod.

Most zoom lenses work well outdoors. However, if you use it indoors, you need to make sure that there is enough light to keep the aperture of your zoom lens at f/2.8 during the whole zoom process.

Special purpose lens

Macro lens is used for very close shooting (below). This kind of lens allows you to focus on a small range and correct the distortion caused by close focus. This kind of lens is usually called macro lens, which is a bit inaccurate. Some zoom lenses also have a macro effect. Their focus will be closer than zoom lenses without macro, but not as close as fixed-focus macro lenses.

Macro lens can make the camera very close to the subject, without using other accessories, such as telescopic tube. When your lens is close to the subject, the depth of field will be very narrow, and the scene will be clear only in a small distance.

Parr found that he could show more details of the theme by getting closer to it. He said, "Although I never know what a one-eyed candy on the earth can tell us, it seems to tell us something. This is the mystery of photography. "

The fisheye lens is a wide-angle lens with the largest viewing angle. The fisheye lens has a very wide viewing angle, and some of them are even larger than 180. The fisheye lens exaggerates the size difference between the main body close to the camera and the main body far from the camera to the limit. Barrel distortion is inherent in their design, that is, the straight line will appear visual bending at the edge of the image. Fisheye lenses can also produce great depth of field. It is clear from the part near the camera to the part far from the camera. This is not a lens used in any occasion or even many occasions, but it can make an impressive scene (below).

Fisheye lens interprets active youth through distorted space. This photo shows the typical characteristics of fisheye lens: the depth of field is very large, the size of the part of the subject near the camera is obviously different from that in the background, and the barrel distortion bends the straight line in the image. Simmons chose the expressive fisheye lens to enhance the audience's vertigo and highlight its saturated and strong surrealism.

Soft-focus lens, also called portrait lens, will have a deliberate distortion effect. Its purpose is to take softer and more hazy photos and soften some details, such as wrinkles.

The perspective control lens brings the regulator of the viewfinder camera to other kinds of cameras. When the camera is tilted, move the lens up, down or sideways to avoid parallel lines (such as lines of buildings) from tilting.

Catadioptric or reflective lenses are similar in design to reflecting telescope. It uses curved mirrors and glass elements in the lens. Therefore, its focal length is very long, but the lens size is moderate, which is smaller and lighter than the lens with only glass elements of equivalent focal length. The aperture of the "cat's eye" lens is fixed, and the typical aperture is usually f /8 or f/1 1.

A stable image can be built on a stable lens. The micro motor can adjust the position of special floating lens elements. Sometimes the same lens will produce poor visual effects because of instability.

Manual focusing lens

By focusing manually, you can select the clearest part of the image you want. Which part of the image is the most important? Which part do you want to emphasize? Which part do you want the audience to see first? If you are shooting people, focus on the eyes. If your subject has an angle with you, or you are too close, then his eyes may not be able to shoot clearly. According to the effect you want, decide which eye clarity is more important.

The closer you are, the more important it is to focus accurately. If you are 0.6m away from the subject, the depth of field will be very small, so you need to focus carefully, because only a narrow area will be clear from far to near. If you are 60 mm away from the subject, everything at this distance and above will become clear.

Manual focusing is like tuning a guitar. Adjust it a little first and then call back. If you want to make the image clear by focusing, then you should adjust the focal length slightly to make the image out of focus, and then adjust it back to make the image clear, so that you will know exactly when your subject will be the clearest.

You can use the instant view function of digital camera to focus. All portable digital cameras project images on the sensor at equal distances, and you can observe and design your images on a small viewfinder. Some digital SLR cameras can also set the same display effect, although this usually requires you to lock the mirror. Usually, live view or live preview can be well enlarged, which is convenient for accurate manual focusing of the enlarged picture. This is especially true when taking pictures with a tripod, such as still life. Any single-lens reflex camera will have less vibration when it is exposed, and the photos will be clearer. If a tripod is used, the photos will be clearer.

Follow focus technology helps you focus on moving objects better. If a runner runs towards you, you need to adjust your focus synchronously with the change of the distance between you.

One of the ways to learn how to focus is to practice focusing on people who are close to you or far away from you. After that, you can practice focusing on faster objects, such as the license plate of a moving car. If still life photography is your only major, you don't need this skill, but if you want to shoot high-speed moving objects such as football matches, racing cars and dancers, this skill is necessary.

Note: Don't forget that shutter speed and aperture size also play an important role in your final imaging. If your shutter speed is not fast enough, no matter how accurate your focus is, the moving object will appear blurred. If your aperture is not small enough, the most important part will be in focus well, but the part as important as it is likely to be out of focus.

Clear focus will be very eye-catching when you shoot, and you will naturally focus your eyes and camera on the most important part of the picture. Sharp focus is a signal that makes the audience pay special attention to a certain part of the image, especially when other parts of the image are not clear.

Manual focusing: use the viewfinder

Single-lens reflex cameras and viewfinder cameras use frosted glass viewfinder. The light is refracted through the lens to an etched translucent plane similar to ground glass. This ground glass creates a surface from which the audience can see the image from the other side. When you rotate the lens back and forth to focus, the ground glass display will be clear (left) when the scenery is clear, and not clear (right) when the scenery is blurred.

The reflex camera may also include a micro-prism, and there will always be a circle flashing on the screen until the focus is successful. Sometimes, the split image focus help will show compensation until the image is in focus correctly.

The rangefinder linkage camera has the function of image splitting and focusing, and two images of the same subject are superimposed on the focusing screen for operation. One image passes through the viewfinder and the other image is reflected by a rotating prism connected to the lens. Only when the lens is clearly focused on the subject will the two images be accurately superimposed. The red circle on the image is called focusing aid. They will not appear in the viewfinder.

Note: If your eyesight is poor, you will often find it difficult to focus manually. The viewfinder on some cameras can be adjusted according to your vision like glasses (called diopter). Some cameras provide accessories called refractive lenses, which will have the same effect if they are fixed directly on the eyepiece with screws. Your optometrist can tell you what kind of suitable refractive lenses to buy.