Advantages and disadvantages of SLR

Many people who want to buy a SLR may not know why it is called this name. The full name of SLR is "Single Lens Reflex Camera". Hong Kong and Taiwan are accustomed to use the simple "Single Lens Camera" to refer to it; the English translation is "SingleLensReflexCamera", referred to as "SLR." The "reflective" in the phrase refers to the internal lens of the camera. The reflector component is precisely because this type of camera directly uses the lens to view the view and then uses the reflector to refract light and shadow, and is finally seen by the photographer's naked eyes through the viewfinder. Therefore, the SLR has the advantage of no aberration in the viewfinder, and it must be opened before shooting. The lens cap is required to capture the view, but when the shutter is pressed, in order to allow the film or photosensitive element behind to obtain light and shadow, the reflector located inside the fuselage must have a process of rising and falling, resulting in a weak shutter time lag. It blocks the sight of the viewfinder and produces loud noise, resulting in a blind spot at the moment of shooting and loud working noise. The reflector is undoubtedly one of the keys to the optical structure of an SLR camera (another important component is the pentaprism or pentaprism. Mirror), which achieves the advantages of SLRs and determines the shortcomings of SLRs. In addition to shutter lag, instantaneous blind spots and operating noise, the indispensable and tilted reflector and the pentaprism or pentagonal mirror located on the top of the fuselage also make it possible. The body size of SLR cameras is generally relatively bulky; in the electronic and digital age, the addition of new components such as built-in flashes, image sensors, and LCD screens has made the thickness of SLR cameras continue to increase. In addition, the lens diameter and length have also increased. It is relatively large, so for users who pursue lightweight, the SLR structure is not very satisfactory; but in the eyes of other friends, the large size is not necessarily a disadvantage, but the small size is not advantageous. In order to illustrate the advantages of the SLR, it is inevitable to have it. Let’s mention the rangefinder structure that is “opposite” to the SLR system in many aspects. These two are exactly the two major design schools of civilian 135 cameras. The fundamental difference lies in the difference in the framing method of the SLR. The center points of the reflector, pentaprism (five-sided mirror) and the viewfinder are all on the same axis, so it is a coaxial viewfinder. There is no direct optical connection between the viewfinder and the lens of an ordinary rangefinder camera (there is no need to open the lens cover. It can also capture the view) and is not on the same axis, hence the name "SLR" and "rangefinder". They have different technical advantages, resulting in the finished machine having distinct strengths and weaknesses in some performance indicators. Compared with SLR cameras, rangefinder cameras have the advantages of being lighter in size, with less operating vibration and noise. In theory, they can also have better imaging capabilities within a specific focal length. At the same time, their viewing range is larger than that of SLR cameras. Some rangefinders can see a small part of the picture outside the shooting frame, while SLR viewfinders can often only see images within the shooting frame or even smaller than the shooting frame. In contrast, rangefinders naturally allow the photographer to see more The shortcoming of the rangefinder structure is that because the viewfinder and the lens are not on the same axis and at the same height, there is a certain aberration between the viewing field of view and the actual shooting field of view, and it cannot be as direct as the SLR system. "What you see is what you get" (but some high-end rangefinder cameras have automatic parallax correction). Obviously, both have their own advantages in terms of framing. Today, as technology advances rapidly, the birth and development of electronic viewfinders have begun to bring about fundamental changes. In the field of civilian products, rangefinder optical viewfinders are gradually declining, while SLR optical viewfinders still have relatively strong vitality. Looking back at the film era, the SLR, which came out later and has a louder appearance and operating noise, has won the favor of more and more mid-to-high-end users in the market competition. Whether they are professional journalists or photography enthusiasts, SLR cameras were once their first choice. An indispensable choice. The root cause is that the SLR structure has innate advantages that rangefinder cameras cannot match in terms of macro and telephoto shooting capabilities. Therefore, it is easier to obtain a comprehensive range of focal lengths and a shooting range suitable for both distances and distances, thereby enriching the subject matter of photography. However, rangefinder cameras have not died out due to the increasing popularity of SLRs. Instead, they have become a powerful tool for documentary and humanistic photography by virtue of their imaging quality advantages in short and standard viewing angles and their lightweight and quiet structural characteristics. In fact, the once-popular film-type point-and-shoot cameras were also an important part of rangefinder products; therefore, in terms of market share, rangefinder cameras may have had a larger user base at that time.