Specifications: ETX-90EC Astro Telescope
Optical design . . . . . . . . . . . . . . . . . . . Maksutov-Cassegrain Primary mirror diameter . . . . . . . . . . . . . . . . . . 96mm (3.78”) Clear aperture . . . . . . . . . . . . . . . . . . . . . . . . . . 90mm (3.5”) Focal length . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1250mm Focal ratio (photographic speed). . . . . . . . . . . . . . . . . . f/13.8 Near focus (approx) . . . . . . . . . . . . . . . . . . . . . 11.5 ft (3.5m) Resolving power . . . . . . . . . . . . . . . . . . . . . . . . . 1.3 arc secs Super multi-coatings (EMC) . . . . . . . . . . . . . . . . . . . standard Limiting visual stellar magnitude (approx.) . . . . . . . . . . . . 11.7 Image scale . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.16°/inch Maximum practical visual power . . . . . . . . . . . . . . . . . . 325X Optical tube dimensions
(dia. x length) . . . . . . . . . . 10.4cm x 27.9cm (4.1” x 11”) Eyepiece . . . . . . . . . . . . . . . . . . . . . . . . . Super Plössl 26mm Viewfinder . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 x 21mm Secondary mirror obstruction (dia.; %) . . 27.9mm (1.1”); 9.6% Telescope mounting . . . . . . . . . . . . . . . fork type; double tine Setting circle diameters . . . . . . . . . . . . . . . Dec.: 3.5”; RA: 7” Input voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 volts DC Motor Drive System DC servo motors with encoders, both axes Slow-Motion Controls . . . . . . . . . electric, 4 speed, both axes Optional Autostar Capability . . . . . . . . . . . . . . . . . . . . . . . yes Hemispheres of operation . . . . . North and South, switchable Bearings:
Altitude. . . . . . . . . . . . . . . . . . . . . . UHMW polyethylene Azimuth . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . PTFE
Materials:
Tube body . . . . . . . . . . . . . . . . . . . . . . . . . . . aluminum Mounting . . . . . . high-impact ABS, aluminum-reinforced Primary mirror . . . . . . . . . . . . . . . . . . . . . . Pyrex® glass Correcting lens. . . . . . . . . . . BK7 optical glass, Grade-A
Telescope dimensions:
. . . . . . . . . . . . . . . . 38cm x 18cm x 22cm (15” x 7” x 9”) Telescope net weight:
(incl. Electronic Controller & batteries) . . 3.5kg (7.8 lbs) Telescope shipping weight . . . . . . . . . . . . . . . 5.8kg (12.8 lbs) Battery Life (approx.):
with Electronic Controller . . . . . . . . . . . . . . . . . . . 45 hrs with Autostar . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 hrs
Specifications: ETX-105EC Astro Telescope
Optical design . . . . . . . . . . . . . . . . . . . Maksutov-Cassegrain Primary mirror diameter . . . . . . . . . . . . . . . . . 116mm (4.56”) Clear aperture . . . . . . . . . . . . . . . . . . . . . . . . 105mm (4.13”) Focal length . . . . . . . . . . . . . . . . . . . . . . . . . 1470mm (57.8”) Focal ratio (photographic speed) . . . . . . . . . . . . . . . . . . . f/14 Near focus (approx). . . . . . . . . . . . . . . . . . . . . . . 4.6m (15 ft) Resolving power . . . . . . . . . . . . . . . . . . . . . . . . . 1.1 arc secs Super multi-coatings (EMC) . . . . . . . . . . . . . . . . . . . standard Limiting visual stellar magnitude (approx.). . . . . . . . . . . . 12.1 Image scale . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.99°/inch Maximum practical visual power. . . . . . . . . . . . . . . . . . . 420x Optical tube dimensions
(dia. x length) . . . . . . . . 12.4cm x 32.8cm (4.88” x 12.9”) Eyepiece . . . . . . . . . . . . . . . . . . . . . . . . . Super Plössl 26mm Viewfinder. . . . . . . . . . . . . . . . . . . . . . . 8 x 25mm right-angle Secondary mirror obstruction (dia.; %). . . 3.3cm (1.32”); 9.4% Telescope mounting . . . . . . . . . . . . . . . fork type; double tine Setting circle diameters . . . . . . . . . . . . . Dec.: 3.81”; RA: 7.8” Input voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 volts DC Motor Drive System . . DC servo motors with encoders, both axes
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Slow-Motion Controls . . . . . . . . . electric, 4 speed, both axes Optional Autostar Capability . . . . . . . . . . . . . . . . . . . . . . . yes Hemispheres of operation . . . . . North and South, switchable Bearings:
Altitude . . . . . . . . . . . . . . . . . . . . . . . . . . . ball bearings Azimuth . . . . PTFE thrust bearing and radial ball bearing
Materials:
Tube body . . . . . . . . . . . . . . . . . . . . . . . . . . . aluminum Mounting . . . . . . ABS, with internal aluminum structure Primary mirror . . . . . . . . . . . . . . . . . . . . . . Pyrex® glass Correcting lens. . . . . . . . . . . BK7 optical glass, Grade-A
Telescope dimensions:
. . . . . . . . . . . . . 43cm x 25cm x 20cm (17” x 10” x 8”)
Telescope net weight:
(incl. Electronic Controller & batteries) . . 6.1kg (13.5 lbs) Telescope shipping weight . . . . . . . . . . . . . . . 8.3kg (18.4 lbs) Battery Life (approx.):
with Electronic Controller . . . . . . . . . . . . . . . . . . . 45 hrs with Autostar . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 hrs
Specifications: ETX-125EC Astro Telescope
Optical design . . . . . . . . . . . . . . . . . . . Maksutov-Cassegrain Primary mirror diameter . . . . . . . . . . . . . . . . . 138mm (5.43”) Clear aperture . . . . . . . . . . . . . . . . . . . . . . . . . 127mm (5.0”) Focal length . . . . . . . . . . . . . . . . . . . . . . . . . 1900mm (74.8”) Focal ratio (photographic speed) . . . . . . . . . . . . . . . . . . . f/15 Near focus (approx). . . . . . . . . . . . . . . . . . . . . . . 5.5m (18 ft) Resolving power . . . . . . . . . . . . . . . . . . . . . . . . . 0.9 arc secs Super multi-coatings (EMC) . . . . . . . . . . . . . . . . . . . standard Limiting visual stellar magnitude (approx.). . . . . . . . . . . . 12.5 Image scale . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.76°/inch Maximum practical visual power . . . . . . . . . . . . . . . . . . 500X Optical tube dimensions
(dia. x length) . . . . . . . . . 14.6cm x 36cm (5.75” x 14.2”) Eyepiece . . . . . . . . . . . . . . . . . . . . . . . . . Super Plössl 26mm Viewfinder. . . . . . . . . . . . . . . . . . . . . . . 8 x 25mm right-angle Secondary mirror obstruction (dia.; %) . . 39.4mm (1.6”); 9.6% Telescope mounting . . . . . . . . . . . . . . . fork type; double tine Setting circle diameters . . . . . . . . . . . . . . . Dec.: 4.3”; RA: 9” Input voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 volts DC Motor Drive System . . DC servo motors with encoders, both axes Slow-Motion Controls . . . . . . . . . electric, 4 speed, both axes Optional Autostar Capability . . . . . . . . . . . . . . . . . . . . . . . yes Hemispheres of operation . . . . . North and South, switchable Bearings:
Altitude . . . . . . . . . . . . . . . . . . . . . . . . . . . ball bearings Azimuth . . . . . . . . . . . . . . . . . . . . . . . . . . . ball bearings
Materials:
Tube body . . . . . . . . . . . . . . . . . . . . . . . . . . . aluminum Mounting . . . . . . . ABS, with internal aluminum structure Primary mirror . . . . . . . . . . . . . . . . . . . . . . Pyrex® glass Correcting lens. . . . . . . . . . . BK7 optical glass, Grade-A
Telescope dimensions:
. . . . . . . . . . 48cm x 23cm x 27cm (19” x 8.9” x 10.8”)
Telescope net weight:
(incl. Electronic Controller & batteries) . . 6.9kg (15.2 lbs) Telescope shipping weight . . . . . . . . . . . . . . 11.4kg (25.2 lbs) Battery Life (approx.):
with Electronic Controller . . . . . . . . . . . . . . . . . . . 45 hrs with Autostar . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 hrs