Three elements of camera exposure: sensitivity (ISO)

Sensitivity refers to the sensitivity of the sensor to light. We can think of it as the water pressure of tap water. When the water pressure reaches a certain critical value, the water quality will deteriorate. In fact, the picture will produce noise, which means that the image quality is poor. < / P > < p > generally speaking, the sensitivity is displayed in 1 / 3 increments. Of course, we can also display in whole file increments, such as 100, 200, 400, 800, 1600 Step values can be set in the cameras. For details, see the instructions of each camera. When the sensitivity is increased by one gear, the exposure is doubled. When the light sensitivity is reduced by one gear, the exposure amount is one-half of the original value. The principle is the same as that of the aperture and the shutter. Here, it should be explained that the three words “gear, block and level” mean the same thing. < / P > < p > the sensitivity can’t be used alone. You have to pull up the aperture and the shutter to work together to work. The relationship between the three elements of exposure is like this. When you do the work, you still have to work together to do a good job. Otherwise, the leaders are not high-minded. But in the process of doing things, they cooperate with each other carefully. You hold me back and I control you. How to say < / P > < p >? I’m shooting with a 50 mm standard lens. The aperture range of the lens is f2.8-f22, but the best imaging aperture of the lens is f5.6-f11. Therefore, when using the shutter priority exposure mode, we should consider the value of the best imaging aperture. In addition, we also need to consider the limit of “handheld fast door speed”. Although you can mount a tripod, the subject also has a shutter If you need to shoot sports news materials with high-speed shutter, because of the poor lighting conditions, you should take a bunch of slow gate films to see if you will be scolded by the leaders, although the slow gate sports will be more artistic. < / P > < p > therefore, when encountering bad light environment, we need to improve the sensitivity. Although it is said that high sensitivity will lead to noise in the picture, when shooting documentary films, we should take pictures first and then consider the problem of image quality. Although it is said that high sensitivity will affect the image quality, too long shutter speed will also affect the image quality. As long as the machine is heated, the noise will be high. Therefore, if you use 6400 light sensitivity during the day and 6400 at night, the image noise is different. You can try it. < / P > < p > if you often need to shoot in a weak light environment, it is recommended to use a full frame body and a large aperture lens. The high sense noise suppression effect of the full frame is better than that of the residual frame, which is the congenital advantage of large bottom. Continue ReadingVideo Number assistant internal test online! Four functions let you send 1g video on the computer

Author: zmhuaxia