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We talked about the influence of the size of the photosensitive element and the focal length of the lens. Let's talk about the aperture today.

The aperture is an indicator of the amount of light in a camera lens, usually expressed as F, such as F2.8, on the lens as a digital scale. The smaller the number after F, the larger the aperture.

The aperture of the lens is adjustable, and the maximum aperture is larger, which means that more light can pass through, which plays an important role in photography.

The influence of aperture on the amount of light input the aperture, shutter and sensitivity can all affect the brightness of the photo. If one is low, the other two should be raised so that the brightness of the photo can be normal.

Large aperture can increase the amount of light, the amount of light is more, in photography has the following advantages.

First, a lower sensitivity can be used. If the sensitivity is too high, it will reduce the quality of the picture. If you can use the aperture to increase the amount of light input, you will not give priority to increasing the sensitivity.

Second, it can improve the shutter speed. If the shutter time is too long, the picture will blur, which often happens at night.

Third, combined with the first two, with a large aperture lens, you can shoot in a more demanding dark environment, which is an incomparable advantage over a small aperture lens.

Special slow door theme slow door, that is, the use of a longer shutter time. For example, use an 8-second shutter to photograph the track of headlights and 20 seconds to photograph the starry sky.

Take starry photography as an example, the brightness of stars is relatively low, so it is necessary to increase the amount of light in order to take a clear picture. But the stars move all the time in the sky, so extending the shutter time does not completely increase the brightness of the stars. Especially when shooting a meteor, the meteor often disappears in two or three seconds, and it is useless for you to use a long shutter time.

At this point, you can only increase the aperture or sensitivity. In a low light environment, too high sensitivity will produce a lot of noise. Therefore, using a large aperture is an effective and harmless method.

The influence of aperture on virtual aperture large aperture can obtain small depth of field, and the virtual ability of large aperture is stronger when other shooting conditions remain the same.

Many friends like to take virtual photos, which is one of the joys of photography with a camera. It is often used in portrait photography and food photography.

The aperture of the variable lens of the aperture is adjustable and can be adjusted to a very small aperture to meet your needs. But the maximum aperture varies, and what you want to look at is the upper limit. The maximum aperture value is also marked on the lens.

The longer the focal length, the smaller the aperture. So the maximum aperture of the zoom lens is also changing, and two values are marked on the lens. For some top telephoto lenses that cost tens of thousands of yuan, the maximum aperture is not particularly large, just because the focal length is too long.

Generally speaking, if you choose a lens with a large aperture, F2.8 is a large aperture, and you can reach this threshold. If the number after F can reach more than 1: 00, it will be a very large aperture. If it reaches 0: 00, it will be amazing.

The daytime light is good, the request to the lens is not high. In a low-light environment at night, the requirements for the lens are more stringent. Generally speaking, if the lens reaches F4 or above, it can meet all kinds of shooting needs. In places with little light pollution, F4 is also the entry requirement for shooting starry sky. But where the environment is poor, the effect of a small aperture is definitely not as good as that of a large aperture.

When shooting virtual subjects, F2.8 is a critical point. No matter how small the aperture is, the virtual effect of short focal length is not obvious. if you want to make it strong, you often have to use a 80mm or even a longer lens. Because short-range and long-focus can also increase the virtual effect.

When choosing a lens, we should also consider other indicators of the lens, such as distortion, wisdom difference, dispersion, resolution and other factors. In this paper, it is discussed only from the point of view of aperture.

This article comes from the official account of Wechat: photography Research Society (ID:shoujiPhotography)

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