Telefocus, like Canon's Xiaobai, the primary telephoto lens is suitable for weddings, celebrations and other things, because the focal length is longer and the aperture is larger, which is suitable for capturing people. A longer one is suitable for capturing sports or something.
Medium coke, generally within 30 to 100, should be considered as medium coke. Generally, there are no photos that are too demanding, and this range is enough.
A short-focus lens can also be called a wide-angle lens. From 28 mm, it's all wide-angle. However, on a digital camera that is not fully equipped, 28 mm is not wide ... a little wider. If it is fully equipped, it is equivalent to the human eye and can see a wide range. This is a wide angle.
Generally, wide-angle and telephoto are more popular because the shooting effect is generally good-good lens+good technology = good film.
What about the aperture size? You may have seen some movies. The theme in the middle is clear, but the background is vague. Or some scenery, the overall situation is relatively clear. This is the influence of aperture size. Matching the aperture, there is a proper term called depth of field. The smaller the aperture value, the larger the aperture, the smaller the depth of field and the more blurred the background; The larger the aperture value, the smaller the aperture, the greater the depth of field, and the clearer the whole photo.
For general landscape photos, you can use an aperture above F6, and for portraits, it is enough to use an aperture around F5. If you take a macro, you can generally adjust it directly to F2.8 (if the light permits).
The problem of aperture can be explained by pinhole imaging: the smaller the aperture, the clearer you can see; On the contrary, the bigger the hole, the more blurred it is.
In addition, the aperture is also related to exposure. When the exposure time is fixed, the larger the aperture, the more light enters and the brighter the image. or vice versa, Dallas to the auditorium
The longer the exposure time, the easier it is to blur the image. At that time, because your hand was shaking, this tiny movement would be captured by the camera. Therefore, the larger the aperture, the shorter the exposure time, and the less prone to image blur.
Therefore, the telephoto Xiaobai mentioned earlier said that its aperture is relatively large. In places like weddings, the films it shoots can also be taken into the light to a great extent, and it is not easy to appear empty.