The working principle of the SLR camera of the micro camera

SLR digital cameras refer to single-lens reflex digital cameras, namely Digital, Single, Lens, and Reflex. Currently, the common SLR digital camera brands on the market are: Nikon, Canon, Pentax, Sony, etc. SLR cameras are now also used by many people on microscopes to become a type of microscopic camera.

How the SLR camera works:

In the working system of the digital SLR digital camera, after the light reaches the mirror through the lens, it is refracted to the above focusing screen and formed into an image. Through the eyepiece and the pentaprism, we can see the outside scenery in the viewing window. In contrast, a typical digital camera can only see the captured image through the LCD screen or electronic viewfinder (EVF). Obviously, the image that is directly seen is more conducive to shooting than the image that is seen by processing.

When shooting with DSLR, when the shutter button is pressed, the mirror will pop up, and the shutter curtain in front of the photosensitive element (CCD or CMOS) will be turned on at the same time. The light passing through the lens will be projected onto the photosensitive element and then reflected. The mirror is immediately restored to its original shape and the image can be seen again in the viewing window. This configuration of the single-lens reflex camera confirms that it is completely shot through the lens, which makes the image seen in the viewing window and the film always the same, and its viewing range is basically the same as the actual shooting range. It is very beneficial to visually compose the composition.

If you want to ask what is the most important part of the camera, I think most people will say: lens! Because its quality directly affects the quality of the imaging. At the same time, the lens is also one of the most important criteria for classifying the camera type and grade. Generally speaking, according to the lens, we can divide the camera into three grades: professional camera, quasi-professional camera and ordinary camera. Both traditional film cameras and digital cameras can be applied to this division.

Professional cameras are also called SLR cameras, and the complete one should be called a single-lens reflex camera. The unique design of the mirrors and prisms of this type of camera allows the photographer to directly view the image through the lens from the viewfinder. After the light reaches the mirror through the lens of the camera, it is refracted to the upper focusing screen and formed into an image. Through the eyepiece and the pentaprism, the photographer can see the outside scene in the viewing window. When shooting, when the shutter button is pressed, the mirror will pop up, the front shutter curtain will open at the same time, and the light (image) through the lens will be projected to the photosensitive part (the traditional camera is film, the digital camera is CCD) Or CMOS) to make it sensitive, then the mirror will immediately return to its original state, and the image can be seen again in the viewing window. The lens of a professional camera can be completely removed and replaced with another lens to achieve different shooting results. There are so many types of lenses for professional cameras, and thousands of dollars and tens of thousands of dollars are cheaper. Many lenses are even more expensive than the body. Such cameras are generally only used by professional photographers.

The lens of a quasi-professional camera is not replaceable, but the lens can be replaced by attaching another lens or lens. Although in effect, its shooting effect is slightly inferior to that of a professional camera, but the price is its advantage. Because the price of a quasi-professional camera plus a complete set of additional lenses and lenses is roughly 10,000 yuan, it is basically equivalent to the price of an entry-level professional SLR camera body. Therefore, the quasi-professional camera is most suitable for use by individual high-end users who have certain photography skills.

Ordinary cameras refer to those lenses that cannot be replaced, and can not be attached to other lenses or lenses. Most of the operations are auto-completed products, which are commonly known as "fool cameras".

We can conclude that the lens refers to the part of the camera that receives the optical object and adjusts it to achieve optical imaging (others such as digital cameras, microscopes, etc. also have lenses, the effect is basically similar). At present, the lens of the camera can be divided into two types, one is the standard lens originally provided on the camera, and generally the camera has its own standard lens. The other is a lens that enhances and expands the camera's original standard lens. We can call them a functional add-on lens. Such as a telephoto lens that increases the camera's shooting distance, a wide-angle lens that increases the viewing angle, and the like. The lens we are talking about here mainly refers to the latter.