M42 camera lens eyepiece adapter to make telescope

EYEPIECE ADAPTER FOR M42 LENSES - TELESCOPE CONVERSION

Many people including myself still own old manual M42 camera lenses which haven´t seen too much use lately. One of mine is a 500mm f/8 telephoto lens which makes a great candidate for building a telescope. Even if you don´t happen to own one, it is pretty easy to find such lenses second hand at very low cost. For a powerful telescope, I recommend an M42 lens with a focal length between 200 and 1000mm, but this adapter will work with any