ED eyepiece 25mm 1.25"

The smaller the focal length of an eyepiece, the higher the magnification when used with a telescope.

Is the distance between the eyepiece and eye, within which the entire eyepiece field of view can still be seen. Longer eye reliefs are recommended for relaxed observing.

The optical elements are treated with ultra-thin coatings. Among others, there are anti-reflective coatings for reducing, and dielectric coatings for increasing reflection.

Homofocal eyepieces in a series have the same focal position.