Understanding the parameters of the lens


If we want to choose a suitable lens, we must first understand the various attributes and classifications of the lens. A camera body can be connected to a variety of lenses, so when choosing a lens, we need to pay attention to the classification and focal length of the lens. As well as the size of the aperture, as well as the imaging quality of the lens.

Classification overview of lenses


First of all, lenses can be classified into fixed-focus lenses and zoom lenses. When shooting with a fixed-focus lens, the photographer needs to use his legs to move the position back and forth for the ratio of the viewfinder and the shooting distance; and if the zoom lens wants to change the shooting distance and the viewfinder the ratio of the size, you can directly adjust the focal length by turning the zoom ring.


Then whether it is a zoom lens or a fixed-focus lens, it will be divided into the wide-angle lens, super wide-angle lens, standard lens, macro lens, telephoto lens, and super-telephoto lens, etc. Then we need to choose according to our shooting needs a shot. For example, a super wide-focus lens is suitable for shooting pictures with a very abstract field of view and a strong perspective effect. What does a standard lens mean, that is, it is close to the perspective effect seen by our human eyes; It can pull distant objects closer and can achieve a relative compression effect on the background space of the subject. The macro lens can shoot the subject closer. At the same time, the framing area will become smaller and the depth of field will become shallower, so a slight shake will make the picture blurred; the magnification will be stronger, and you can capture more specific details.

The basic definition of lens focal length


So how do you understand the definition of the wide-angle lens, standard lens, telephoto lens, and macro lens? Let’s also briefly explain here that a wide-angle lens means that the focal length is shorter than that of a standard lens, and the viewing angle is larger than that of a standard lens. A wide-angle lens is generally defined as a wide-angle lens with a focal length below 35mm. A lens with a focal length below 12mm is called a super wide-angle lens, and the shooting angle can reach close to 180 degrees, and some people call it a fisheye lens; then a lens with a focal length of 12-24mm is called a wide-angle lens, and the shooting angle can reach about 120 degrees; the focal length is 24-24mm.

The differences of 16mm/50mm/200 focal length lens

A 50mm lens is called a standard lens, the included angle will be smaller, and the picture taken will be more concentrated. The focal length above 50mm is called a medium telephoto lens, such as 85mm. Then what we usually call a telephoto lens is generally 100mm Above, the included angle is smaller, and the picture effect will be more concentrated. Therefore, there will be a better sense of space compression and depth of field control.


But the dynamic aperture is different. During the zooming process, the aperture will change with the length of the focal length. The longer the focal length, the smaller the aperture will be. For example, for an 18-135 lens, the rated aperture range is F3.5-F5.6, if there are two aperture parameter marks on the lens, it means that it is a dynamic aperture. When the focal length of the lens becomes larger, the aperture will also change accordingly, that is, the longer the focal length of the lens, The smaller the aperture, F6.3 is the critical point that can be adjusted after the focal length becomes longer. For example, at the 18mm focal length, you can use the large aperture of F3.5, but if we adjust to the 35mm focal length, the maximum aperture can only be opened to F4.5, and when using the 100mm focal length, the maximum aperture can only be used at F5.6 the aperture. At the same time, conventionally speaking, the imaging quality of a dynamic aperture lens is not as good as that of a constant aperture lens. But this is not an absolute value. Rational understanding is required.

Features of wide-angle lenses

The wide-angle lens has the advantages of a short focal length and a large viewing angle. It can shoot a wide range of scenes at a relatively short distance. The foreground is more prominent, and the depth of field is significantly larger than that of standard lenses and telephoto lenses. It is suitable for indoor close-up shooting, and shooting scenes such as mountains, rivers, buildings, and crowds.


Picture taken with a wide-angle lens. Can have a broad background while highlighting the central subject and foreground. In a smaller environment, more scenes can be photographed. At the same shooting distance, the scene obtained is smaller than that shot with a standard lens. When shooting close scenes, perspective distortion will occur, and the sense of distance between the front and back scenes will increase. Because of its long depth of field, it is easy to capture both near and far scenes clearly.


The basic character of wide-angle lenses are that the lens has a large viewing angle and a wide field of view. The scope of the scene observed from a certain point of view is much larger than that seen by the human eye at the same point of view; the depth of field is long, and it can show a considerable range of clarity; it can emphasize the perspective effect of the picture, and is good at exaggerating the foreground and expressing the scene. The sense of distance, which is conducive to enhancing the appeal of the picture. Generally speaking, the application range of wide-angle lenses is relatively wide. Beginners can first choose a wide-angle lens to try out the camera.


Wide-angle lens for action camera


Another cold piece of knowledge worth sharing is: almost all sports cameras are fixed-focus wide-angle lenses. And the setting of this wide-angle lens is also in line with the principle of using sports camera. In order for the action camera to capture more scenes in front of you, this is especially useful when shooting action shots, as it allows you to capture more of the action without moving the action camera.

action camera 4k+
Additionally, action cameras are often used for outdoor activities such as skiing, surfing, or mountain biking, which are fast-paced and expansive environments. Using a wide-angle lens helps capture expansive landscapes and environments, creating a more immersive experience for the viewer. Of course, when shooting close-ups, it can also make the content of the picture richer.
Wide-angle lenses also allow for greater depth of field, meaning more of the scene is in focus from near to far. This is especially useful in action shots, where subjects can move quickly and unpredictably, making it difficult to keep them in focus.


Overall, using a wide-angle lens in an action camera is essential to capturing action, scenery, and the environment in a way that is immersive and engaging to the viewer.