2 In 1 Camera BodyLens Rear Cap Cover PK For Pentax K20D

The camera lens is the most important part of the camera, because its quality directly affects the quality of the captured image. At the same time, the lens is also one of the most important criteria for classifying camera types and grades. Generally speaking, according to the lens, cameras can be divided into three grades: professional cameras, quasi-professional cameras and ordinary cameras. Whether it is a traditional film camera or a digital camera, it can be applied to this division. Lenses can be divided into two categories: zoom and fixed focus. Professional cameras are also called single-lens reflex cameras, and the complete should be called single-lens reflex cameras. The unique design of the mirrors and prisms of this type of camera allows the photographer to observe the image through the lens directly from the viewfinder. After the light reaches the mirror through the lens of the camera, it is refracted to the focusing screen above and forms 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 bounce up, the shutter curtain in front will open at the same time, and the light (image) passing through the lens will be projected onto the photosensitive component (traditional cameras are film, digital cameras are CCDs). or CMOS) to make it sensitive, then the mirror immediately returns to its original state, and the image can be seen again in the viewfinder. The lens of a professional camera can be completely removed and replaced with another lens to obtain different shooting effects. There are many types of lenses for professional cameras, and the prices range from thousands to tens of thousands, and many lenses are even more expensive than the body. Various functions and indicators of the fuselage must rely on excellent optical lenses to complete. Through the image conversion of the lens group in the lens, the best effect of the applicable focal length of the current lens is achieved. How to buy a variety of camera lenses. It depends on the type and route of shooting you are good at to judge which lens you should buy the most.