Extension Tube Macro Ring for M42 42mm Screw Mount Camera

This macro extension tube set is suitable for M42 42mm screw mount camera and lens. Transform your Lens into a Macro Lens. It moves the lens from the film or digital sensor. The closer the focus is, the greater the magnification. Use this set will not downgrade the optical quality of your lens.  Sharpness and Saturation can be still maintained. But they are not meter-coupled. They do not preserve the automatic diaphragm.  It should be used with manual lenses with their own aperture dial. There is no electronic connection between the body and the lens. Automatic lenses can be used with their widest open aperture only. Auto-focus function cannot operate.

When using the extension ring with a DSLR/ SLR, the camera should be set in the 'M' mode