Primary Mirror Cooling Fan

Instead of chosing exotic and incredibly expensive mirror substrates we have chosen to equip this telescope with a primary mirror cooling fan to accelerate cool-down time to ambient temperature. Until a mirror is properly cooled down it will create currents of warm air that will deteriorate the image - no matter which mirror substrate is used. Only after the mirror has cooled down this effect stops.


Parabolical Primary Mirror

The very precisely figured parabolical primary mirror of this telescope is not made of cheap float glass, but rather of BK-7 optical glass that is free of internal stress. Thermic properties are generally better than float glass. At the same time the mirror is way more affordable than more exotic primary mirror substrates that in our opinion bring hardly any advantage at all (see comments under "Primary Mirror Cooling Fan"). For easier collimation the mirrors are properly center marked.

Technical details of the optical tube:

-- Aperture 200mm (8") / focal length 1000mm / photographic speed f/5
-- 94% enhanced reflectivity coatings for a brighter picture
-- Seconcary mirror: 63mm diameter (minor axis)
-- Field illumination: 28mm diam. (100%) / 41mm diam. (90%)
-- Weight: 9 kgs with tube rings and finder
-- Outer diameter: 230mm
-- Tube length: 900mm
-- 2" Crayford focuser with 1:10 dual speed transmission

Scope of delivery:

-- GSO 200mm f/5 Newtonian - Optical Tube Assembly with tube rings
-- 8x50 finder
-- 2" Crayford focuser with 1:10 dual speed transmission and reducer to 1.25"
-- 2" extension tube - to achieve focus with all kinds of eyepieces
-- Dust covers
-- 12V main mirror fan
-- Collimation manual


In our opinion, Newtonians by GSO are superior to other comparable systems:

Since many years, we're GSO distributor and we know about the exceptional quality of GSO telescopes. The optical performance is on a very high (and even!) level. In opposite to other manufacturers, we never see "lemons" from GSO. What is more, a GSO system can grow with your demands:

-- For the 8" GSO Newtonian, we offer a Carbon Tube Upgrade Kit

-- Short back-focus Baader Steel Track Focuser upgrade is possible without the need of new tube bores.

-- We offer secondary mirrors of different sizes according to your special demands (e.g. planetary imaging or deep-sky-imaging with full-size sensors)