takes the initiative in launching the very first 150mm hyperbolic Newtonian
reflective telescope with an extremely-fast focal ratio of f/2.8(15028HNT). It
has garnered a quite large following since its advent. Not indulging in this
great achievement, Sharpstar keeps the creativity and dynamism, introducing
13028HNT to our customers, which has a same focal ratio but a slightly smaller
13028HNT, with a hyperbolic primary mirror,
produces round and sharp stars within the full-frame and supports 44mm image
circle. Compared with the focal ratio of f/4, 13028HNT can attain the same
image quality while save almost half of the exposure time. Besides, due to its
compact and concise design of the telescope tube, it will certainly create a stir
again in the market.
primary mirror is made of Pyrex-alike glass PZ33. The thermal expansion
coefficient is smaller than ordinary glass. The dielectric multilayer coating
makes the primary mirror obtain a highly reflective ability up to 97%. The minor
axis of the secondary mirror is 65mm, enabling sufficient illumination for
full-frame imaging. It’s worth mentioning that, the corrector is renovated to a
two-refractive-lens set, one of which is an ED glass, aiming to simplify the
optical system while enhancing the power in aberration correction.
telescope tube is totally made of high-end carbon fiber material, so the weight
of the telescope can greatly lessen and the overall appearance may artistically
build up. All the component parts are from CNC constructed metals. The pair of
tube rings feature pierced design. It may increase the production cost, but
will absolutely offer extraordinary customer experience because of its
lightweight and detail-oriented design concept.
focuser is a 2.5" rack-and-pinion device. It's equipped with coarse
as well as fine adjustment hand knobs to further improve the focusing
precision. The focuser is tapped with M63 thread which can be switched into a
more general M48×0.75 thread with a proper adapter ring(included). Thus the
users may have a wider range of options in connecting other astronomy
accessories to the focuser. The back-focus is standard 55mm(starting from the
base of the mounting thread on the adapter ring's housing), which is makes it
easy to attach a camera with its standard backfocus.
versatile handle and a standard Vixen-style dovetail plate are also included in
the 13028HNT package, which may be of convenience for users to attach other
potential accessories and to place the telescope on various equatorial mounts.