Introduction:M42 Lens to Nikon F AI Ring AdapterMake M42 mount lenses (Zeiss, Pentax, Praktica, Mamiya, Zenit) can be used on Pentax camerasThere is no ROM connection on the ring so diaphragm control of the lens is set manuallyIt is possible to use Macro rings and other accessoriesIt not allows to infinity focusMaterial: Coppercolor : Silver NOTICE: Although the lens will fit physically, automatic diaphragm, auto-focusing, or any other functions will not operate correctly while using this adapter. In this case "stop-down mode" will need to be used when metering since the lens does not have the ability to have its aperture controlled by the camera body. You can shoot with manual mode or aperture priority modeSuitable for:Lens: M42 mou.
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