The relationship among aperture, shutter speed and sensitivity ISO in photography.

Generally, the sensitivity is twice as high, and the single camera is 80, 100, 200, 400, 800, 1600, and the shutter position is 1,12, 1/4,/kloc-.

Next to the first gear is the aperture level 2, 2.8, 4, 5.6, 8, 1 1 6, 22, 32, and next to it is the first gear. The smaller the f value, the larger the aperture, that is, 2 is the largest and 32 is the smallest.

Aperture: Aperture controls luminous flux. The larger the aperture, the more light passes through it. Generally, a large aperture can highlight the theme and achieve the effect of blurring. The smaller the aperture, the less light enters. A small aperture can get a longer depth of field, which is more suitable for shooting scenes with large scenery.

Shutter: Shutter speed is the length of exposure time. The aperture is set to a certain value. The faster the shutter, the less light enters. The slower the shutter is, the more light will enter. The faster the shutter can shine on water droplets, the slower the shutter can shine, and so on.

Iso: Iso: the iso responsible for controlling exposure. If the iso aperture is increased by one step, it can be reduced by one step, or the shutter can be accelerated by one step. If you reduce the shutter by one step, you have to slow down or enlarge the aperture by one step. Make adjustments as needed. If iso is high, there will be a lot of noise, especially dc's dry control ability is not strong. The smaller the iso, the cleaner the photo.

After determining the correct exposure of the scene, different exposure combinations can be changed to achieve different effects. For example, the correct exposure value of a scene under ISO 100 is F8,1125, then you can choose F5.6, 1/250-F65438+. To control the expressive force of the picture, there is a common law "reciprocal rate" in photography-that is, to ensure correct exposure, you can enlarge the first aperture and raise the first shutter at the same time, or narrow the first aperture and lower the first shutter at the same time. This is a trade-off relationship. To enlarge or reduce the aperture by several steps, we have to speed up or slow down the shutter by several steps accordingly. Only in this way can we maintain the correct total exposure and ensure the picture quality. The picture effect is achieved by constantly changing the combination of aperture and shutter. Of course, this reciprocity rate sometimes fails, such as shooting the starry sky on a moonlit night and other special environments. Here, it is not a simple reciprocity rate that can be solved. More depends on the photographer's experience and skills, which need to be summarized through practice.