This very high quality zoom eyepiece delivers a particularly flat field of view, high contrast
and excellent colour rendition. It is recommended for astronomical and terrestrial use as well
as for Solar observing with an appropriate telescope.
The eyepiece provides an apparent field of view of 60°-40° and continuous focal lengths between
7.2mm and 21.5mm, this range particularly suits SCT type telescopes that will operate at their
highest magnifications at around 7.5mm under reasonable conditions. When used in conjunction
with a 2x barlow the eyepiece will reach the maximum possible magnification for a f4.8 Newtonian
telescope thus making it very versatile with a variety of telescopes of different optical designs,
focal lengths and focal ratios.
The excellent mechanical construction and finish when combined with a sizeable 15mm eye relief an
adjustable twist-type eye cup make these eyepieces comfortable to use. In addition the eyepiece is
parfocal and as such there is no need to refocus when changing magnifications.
The optical train consists of seven lenses in four separate groups, all optical surfaces are broadband
fully multi-coated and all lenses feature blackened edges, the eyepiece also benefits from internal
baffling. These features reduce internal reflections to an absolute minimum and help to significantly
The Eyepiece has a 1.25" nosepiece and is threaded for filters. It weighs 155 grams, measures 81mm
tall (including the nosepiece) and has a 48mm maximum diameter.
For an even higher specification zoom eyepiece please consider the
Opticstar XL 7.5mm-22.5mm ZOOM.