The close-up adapter ring is installed between the lens and the body (directly attaching the lens, not the reverse adapter ring), lengthening the lens barrel, and using the principle of skin cavity photography to achieve the effect of super macro shooting. The close-up adapter is installed between the lens and the SLR body. It requires manual settings and manual focus throughout the entire process. The lens should be very close to the object being photographed when taking pictures. It is generally used for local macro photography, and the macro effect is good. For close-up lenses. When using a close-up lens without a manual aperture, the aperture defaults to the smallest aperture. 7mm or 14mm or 28mm hight, light weight, and easy to carry. Some automatic adapters can be linked to the camera's aperture in addition, the structure of the adapter is extremely simple and generally not easy to damage,for Extension Adapters Accessory Lens Adapter for Camera. The M42 close-up adapter can be used for reshooting, and is divided into three adapters 1.2.3. The adapter is placed between the SLR body and the lens, and can be combined in any way to obtain the required magnification. The M42 close-up lens has a total of three sections, which can be used alone or together, but the aperture cannot be linked. The three sections are 7mm, 14mm, and 28mm respectively. With the 50mm header, it can achieve a 1:1 magnification. The conversion formula is: magnification = adapter ring length or lens focal length. According to this, multiple adapter rings can also be combined with different lenses to achieve the required close-range effect. Name:M42 close-up adapter Function:Macro (1) The default value of the aperture is the minimum value and the maximum aperture value. Adjust it before installing the close-up aperture. It cannot be adjusted after it is installed(except for old lenses with aperture rings) (2) Unable to focus automatically, requiring compl