Brief introduction of SLR digital camera

SLR camera refers to the use of a lens to view and image at the same time. When taking pictures, the light is reflected to the optical viewfinder through the reflector and pentaprism (or pentaprism). At this point, you can see the shot view from the viewfinder. After the shutter is pressed, the reflector is lifted, the shutter is opened, and the light directly enters the film, thus completing an exposure. Because both framing and imaging use one lens, SLR cameras can achieve the so-called "what you see is what you get", which is the biggest advantage of SLR cameras over paraxial and double-reflex. Digital SLR cameras naturally adopt digital painting, that is, DSLR(Digital；; Single; Lens; Reflection).

First, you can change the lens. There are wide-angle lenses that are good at taking scenery and standard lenses that are good at taking portraits. If you like shooting sports games or performances, telephoto lenses can help you. If you like to shoot close-up works such as flowers and insects, you can also choose a macro lens. This not only greatly expands the application scope of digital SLR, but also ensures the best optical quality of various lenses in their respective professional fields, which is irreplaceable by ordinary consumer digital cameras. Secondly, digital SLR cameras all use large-size photosensitive elements (CCD or CMOS), and the area of a single pixel is several times that of ordinary card DC, so the images taken are more delicate and smooth, with less noise and wider dynamic range. Especially in low light and high sensitivity shooting, the two are like worlds apart. Thirdly, digital SLR cameras have faster focusing speed and smaller shutter lag. Unlike consumer card cameras, after pressing the shutter, the image you take is not what you want. Fourthly, digital SLR cameras have stronger depth of field control ability, and it is easy to take photos with blurred background, which is what many people yearn for. Fifth, digital SLR cameras have more powerful post-processing capabilities. All digital slrs support RAW format (raw data format). Compared with the JPG format used by the card camera, the post-processing scope is wider, and the exposure, white balance, saturation, contrast and tone can be finely adjusted in the later stage to ensure the final imaging quality to the greatest extent.

First, in the case of being far away from the subject or having special requirements, general digital cameras can't reach it. Digital SLR cameras have rich lens groups, which can meet the shooting needs of different occasions.

Secondly, in the case of weak light, digital SLR cameras can use high sensitivity to ensure high shutter speed and high image quality, but ordinary digital cameras can do nothing.

Third, in sports competitions, only extremely fast focusing can capture the moment you want, which is also the death hole of ordinary consumer digital cameras.

Fourth, in order to highlight the shooting theme, the background needs to be "killed", and ordinary digital cameras can only sigh.

principle of operation

In this system, after the light reaches the mirror through the lens, it is refracted to the focusing screen above to form an image. Through the eyepiece and pentaprism, we can see the scenery outside in the observation window. In contrast, ordinary digital cameras can only see the captured images through the LCD screen or electronic viewfinder (EVF). Obviously, the directly seen image is more conducive to shooting than the processed image.

When shooting in DSLR, press the shutter button, the reflector will pop up, and the shutter curtain in front of the photosensitive element (CCD or CMOS) will be opened at the same time, and the light passing through the lens will be projected onto the photosensitive original, and then the rear reflector will be restored immediately, and the image can be seen in the viewfinder. This structure of the single-lens reflex camera ensures that it is shot through the lens, so that the image seen in the viewfinder is always consistent with the image on the film, and its framing range is basically consistent with the actual shooting range, which is very conducive to intuitive framing and composition.

In addition, a major feature of SLR digital cameras is that they can change lenses of different specifications, which is an inherent advantage of SLR cameras and incomparable to ordinary digital cameras.

Applicable object

Simply put, SLR digital cameras are not suitable for any users. First of all, it is one thing to have the necessary professional knowledge. Secondly, to make good use of SLR digital cameras, we must match different types of lenses, which is likely to make the cost of lenses higher than the cost of buying digital cameras.

Moreover, when traveling abroad, the weight of camera bag with lens group is much higher than that of ordinary camera, which will become a serious burden in the travel process. In addition, when changing the lens of SLR digital camera, the photosensitive element will be directly exposed to the air, so we must also pay attention to the maintenance of the camera when using it. Therefore, although the shooting quality of SLR digital cameras is higher and the price has dropped a lot now, it is not suitable for all users, and users should choose according to their own needs when purchasing.

Photography enthusiasts, professional photographers, sports photographers, journalists, journalists, business reporters, new SLR players who enjoy the fun of manual operation, photography enthusiasts, etc. Are big fans of SLR digital cameras.

Five advantages

1, advantages of image sensor

? For digital cameras, the photosensitive element is one of the most important core components, and its size is directly related to the shooting effect. In order to achieve good shooting effect, the most effective method is not only to increase the number of pixels, but also to increase the size of CCD or CMOS. Whether using CCD or CMOS, the sensor size of digital SLR cameras is much larger than that of ordinary digital cameras. Therefore, the number of sensor pixels of digital SLR is relatively large (currently the lowest is 6 million), and the area of a single pixel is four or five times that of a civil digital camera, so it has excellent signal-to-noise ratio and can record a wide brightness range. The image quality of a 6-megapixel digital SLR camera definitely exceeds that of an 8-megapixel 2/3-inch CCD camera.

2. Rich lens selection

? Digital camera is a product of optical, mechanical and electrical integration, and the performance of optical imaging system is also very important to the final imaging effect. Having an excellent lens is as important for imaging as the choice of image sensor. At the same time, with the cost reduction of image sensor, image engine and storage equipment, the proportion of optical lens in the cost of digital camera is also increasing. All brands have huge autofocus lens groups, from super wide angle to super telephoto, from macro to soft focus, users can choose matching lenses according to their own needs. At the same time, due to the large sensor area, it is easier for digital SLR cameras to obtain excellent imaging.

3. Fast response speed

? The start-up speed of digital SLR is only a few hundred milliseconds, and continuous shooting is also very fast. Consumer cameras, on the other hand, are pure electronic shutters, which has a serious shutter lag problem. This weakness can be called the weakness of consumer digital cameras, so you can shoot still life, but it is not suitable for capturing moving objects-the image you get is often not the action when you press the shutter. Response speed is the advantage of digital SLR. Because their focusing system is independent of imaging equipment, they can basically achieve the same response speed as traditional SLR, which makes users handy in news and sports photography.

4. Excellent manual control ability

Although the camera's automatic shooting function is getting stronger and stronger today, a user who has certain requirements for photography will not be satisfied with shooting only in automatic mode because of the ever-changing environment and shooting objects. Digital SLR can easily manually zoom, manually set shooting parameters and so on, and can also take some special shots. But many consumer cameras are automatic (especially card machines). Most cameras have no manual zoom ring, so they can only zoom automatically by motor. Because the speed of zooming is slow, many shooting opportunities will be lost. Many people think that automation is better than manual operation, which is really a misunderstanding. Cameras with automatic function but no manual function are often low-end cameras, because the accuracy and speed of automation are far less than that of manual operation.

5, rich accessories

An important difference between digital SLR and ordinary digital camera is its strong expansibility. In addition to continuing to use additional lenses such as polarizers and interchangeable lenses, you can also use auxiliary equipment such as professional flashlights to enhance your ability to adapt to various environments. For example, high-power flash, ring macro flash, battery handle, timing remote controller, these rich accessories make digital SLR adapt to various unique needs, while ordinary digital cameras are greatly inferior.

In addition, the positioning of SLR digital cameras in digital cameras is now a high-end product, so the area of SLR digital cameras is much larger than that of ordinary digital cameras in terms of the area of photosensitive elements (CCD or CMOS) related to the photographic quality of digital cameras, which makes the photosensitive area of each pixel of SLR digital cameras much larger than that of ordinary digital cameras, so each pixel can show more detailed brightness and color range, which makes the photographic quality of SLR digital cameras significantly higher than that of ordinary digital cameras.