Several reasons for cracks in the film inside the camera lens, and how to prevent this from happening

In the photography process, the camera's aperture value and shutter speed settings are very important. Aperture value mainly controls the size of the hole that light passes through, while shutter speed controls how long it takes for light to hit the film. Only by setting both just right can you achieve the most satisfying exposure. Unfortunately, many photographers become distressed because they cannot achieve satisfactory results in this regard. The reason is actually very simple: they always use completely different methods to set the aperture value and shutter speed, and the results are of course unsatisfactory.

Let us first take a look at how to choose the appropriate aperture value. Choosing different aperture values ??will allow different apertures of light to pass through the lens. The larger the aperture, the more light passes through, and vice versa. When you set the aperture value to its maximum value, the value of the aperture value F is at its minimum value. And when you gradually close the lens or reduce the aperture value, the corresponding value will become larger and larger. And this just makes many people feel at a loss. Why does the larger the aperture, the smaller the value; the smaller the value, the larger the aperture? In fact, the size of the F number is not the size of the entire aperture value, but only part of it. For example, the aperture value of f-8 is actually larger than 8. In fact, as long as you accept this point of view, this phenomenon is relatively easy to remember: the larger the value, the smaller the aperture; the smaller the value, the larger the aperture.

Concerning the control and selection of shutter speed, to put it simply, the shutter is equivalent to a curtain in front of the film. The intensity of the light projected on the film is determined according to the size of the curtain. This size control uses time to control the so-called shutter speed. Shutter speed, like aperture F value, can only represent some parameters. 15 means 1/15 second, while 30 means 1/30 second, which is twice as fast as 1/15 second; correspondingly, 60 means 1/60 Second. At slower shutter speeds, the first curtain value indicates how quickly the shutter opens, while the second curtain value indicates how quickly the shutter closes. But at faster speeds (such as 1/125 second or higher) the two curtains move together, allowing only a narrow ray of light to be projected from one end of the film to the other. The faster the shutter speed, the narrower the slit that allows light to enter, and the less light is projected onto the film. On some cameras, the shutter curtain is designed to move vertically, but the principle is the same.

Many readers may have this question: "Since we can use aperture or shutter speed alone to control the light projected on the film, why do we have to consider both aspects every time we shoot?" What's the situation? "In fact, the answer is very simple. For a photographer who hopes to shoot higher-quality images, he will not only be satisfied with the appropriate exposure, but also hope to shoot higher-quality images. It should be pointed out that aperture and shutter always work together, and they always influence and restrict each other. Without changing the external light, no one can change the intensity of light captured by the lens, and the same is true for the light projected onto the film. If you need to get the most appropriate exposure effect, you must combine the two adjustments well. If you change the F value to make the aperture smaller, you must set the shutter speed slower. On the contrary, if the aperture value becomes larger, the shutter speed needs to be set faster. We can call this adjustment "reciprocity".

When the aperture value is set to f-4 and the shutter speed is 1/500 second, the exposure effect is the same as when the aperture value is f-5.6 and the shutter speed is 1/250 second. At this time, another reader may come out and think, "My camera has automatic settings and can automatically find the best combination of aperture value and shutter speed, so there is no need to set them." It is worth reminding everyone that although your camera is set automatically, can you guarantee that it will not make mistakes every time it is used? So when you use an automatic camera, you have to pay attention to the aperture value and shutter speed of the camera every time you use it.

If you can do this, I believe your photography skills will be greatly improved. Even if you meet a professional photographer, you don’t have to be humble and ask for advice on photography skills!