How to match the aperture shutter sensitivity of Nikon D90 to achieve the best effect?

1. The aperture value f is inversely proportional to the optical input.

The aperture size is expressed by the value of f, the larger the value, the smaller the aperture, and the smaller the value, the larger the aperture. The smaller the f value of the aperture, the more light enters per unit time (because the aperture of the aperture is large), and the amount of light entering at the upper level is exactly twice that of the lower level.

For example, if the aperture is adjusted from f8 to f5.6, the amount of light entering will be doubled, that is, the aperture will be enlarged by one level. When buying lenses, the size of the aperture is a very important factor, which directly affects the price. A large aperture lens is much more expensive than a small aperture lens. Large aperture can perform better in dark environment, get more light without changing the shutter speed, and let the photos be exposed normally.

Application:

At present, the aperture of professional zoom lenses can generally be opened to F2.8, and fixed-focus lenses such as CANON50MM can be opened to 1.4! Large aperture can not only get more light, but also get the effect of shallow depth of field (the so-called depth of field is the range where the focal length can still be clear before and after a certain point).

The larger the aperture, the shallower the depth of field. In layman's terms, it means that the subject is clear, the background is blurred, and the theme is highlighted, which is often used for portrait shooting.

The smaller the aperture, the greater the depth of field, that is, the foreground and background are relatively clear, which is suitable for taking landscape photos. Of course, controlling the depth of field is not only related to the aperture size, but also related to the lens focal length and shooting distance.

2. The shutter is proportional to the amount of light entering.

Shutter is a mechanical or electronic device that controls the exposure time, and it is a device that blocks light from hitting the front of the lens. Generally speaking, the larger the shutter time range, the better. Controlling the light entering time is the basic function of the shutter. It cooperates with the aperture to meet the needs of exposure. In order to make it easier for everyone to understand, we can also say that the shutter is the control time for the camera to keep the currently set aperture size. The expression of shutter speed is also set with corresponding numbers, such as1/30s,1/60s, etc. They represent the time to keep the currently set aperture size at 1/30 seconds and 1/60 seconds respectively.

Application:

When shooting moving objects, such as a ball game, birds, the shutter should generally be set at 1/300 seconds or more to avoid the photos from being burnt!

When shooting a still object, the shutter speed should not be lower than 1/30 seconds, because according to statistics, when shooting with a handheld camera, the stability of the hand is so great that it stays within the time range of 1/30 seconds.

4 Drag the picture from the gallery on the right to here.

3. Combination application of shutter and aperture

Scenery and people in different shooting conditions have different requirements for shutter or aperture. The combination of different shutter speeds and aperture sizes can get the same exposure. What does this mean?

For example, there are two sets of exposure combinations. A. shutter speed 1/30 seconds, and aperture f value of 5.6. B The shutter speed is1/60s, and the aperture f value is 4. Although the aperture and shutter values of the two groups are not equal and the exposure is the same, it does not prove that the photos taken are exactly the same!

4. Definition and application of sensitivity ISO

The so-called sensitivity refers to the ability to perceive light, that is, the ISO value that is often seen. ISO values are usually ISO 100, 200, 400 or higher. Generally speaking, in the case of low ISO or low sensitivity, the picture is clearer and more detailed. And high ISO can cope in dark environment, but high ISO will increase the dry spots on the photos! Therefore, if possible, it is best to use low ISO. These three parameters are usually adjusted when taking pictures with a digital camera. When I take pictures, I first consider the aperture size, and then the shutter speed. ISO is the last consideration. In the case of fixed aperture, the setting of ISO value is generally based on the shutter speed.