Engineered to Al Nagler's uncompromising standards, the entry-level Tele Vue Plossl 55mm Eyepiece has the longest focal length available in their entire catalog to produce a low magnification for both near and deep-sky observations on OTAs outfitted with larger focuser drawtubes.
It is made using diffraction-limiting high-index glass lenses in a 4-element/2-group configuration to keep light on-axis and reduce astigmatism and edge-aberrations across its generous 50° apparent field of view. Fully multi-coated optics, blackened lens elements, and anti-reflection threads complement the optical components to improve contrast and light transmission, while limiting its loss. Its exceptionally-long 38mm eye relief allows users the room to back off from the eyecup for a more comfortable viewing experience with a reduced risk of accidental contact with the eyepiece lens, which can cause vibrations and interfere with views. Ideal for fast-focal ratio OTAs, the eyepiece features a 2" barrel to be compatible with larger focusers and accessories, which allows more light into the eye and creates the long eye relief; and a convenient fold-down rubber eyecup, and a rubberized textured collar to ensure a secure grip when handling it.