Meade Instruments Astro-Tech AT80ED - Manual

astro-tech AT80ED
from Astronomy Technologies
Thank you for choosing this Astro-Tech AT80ED high-
performance ED refractor.
The images from its fully-multicoated ED (Extra-low
Dispersion glass element) air-spaced doublet optics are
virtually free of the annoying violet haloes of chromatic
aberration (spurious color) that are typically seen around
the Moon, planets, and bright stars in lesser refractors.
Precision-made, with many useful mechanical features
(such as a rotating dual-speed focuser and a very flexible
split ring plus dovetail mounting system), the AT80ED is
Aperture ................................................... 80mm (3.1”)
Focal Length .................................................... 560mm
Focal Ratio ............................................................... f/7
Objective Type .... air-spaced doublet with ED element
Optical Coatings ................................ fully multicoated
Resolving Power (Dawes’ Limit) ...... 1.45 arc seconds
Visual Limiting Magnitude .................. 12.0 maximum
Light Grasp (versus the eye) ............................... 131x
Field Stops ... two glare-reducing baffles in optical tube
Focuser ............................... dual-speed Crayford-type
with 11:1 reduction ratio fine focus
(a 10:1 ratio Feather Touch focuser is optional);
360° rotating camera angle/observing angle adjuster;
and 2” and 1.25” compression ring eyepiece holders
Focuser Travel ....................................... 3.35” (85mm)
with millimeter scale on drawtube for repeatable focus
Lens Shade ................................................. retractable
a clear step ahead of competitive scopes.
At its exceptionally low price, we believe that you will
find that the mechanical and optical performance of your
AT80ED is little short of astonishing.
This instruction sheet will provide you with information
on how to get the most out of your new telescope, and
how to properly maintain your telescope so it can give
you a lifetime of observing enjoyment.
Please familiarize yourself with your telescope’s parts
and functions before operating it for the first time.
Astro-Tech AT80ED Doublet Refractor Specifications
Objective Lens Cover ............................. slip-on metal
Tripod Mount ............. dual split hinged tube rings with
Vixen-style dovetail for direct mounting on
Astro-Tech, Celestron, Meade, and Vixen mounts
Tube Diameter ............................................ 90mm o. d.
Tube Length (lens shade retracted) ........ 18” (457mm)
Tube Length (lens shade extended) ... 21.75” (527mm)
Optical Tube Weight ..... 6.8 lbs (3.09 kg) with standard
focuser; 6.45 lbs (2.93 kg) with optional Feather Touch
focuser (both weights include rings and dovetail)
Case .................................. aluminum-frame foam-fitted
lockable hard case, with carrying handle
Case Dimensions .................... 20.75” x 12.75” x 8.75”
Lowest Usable Power ............... 14x (40mm eyepiece)
Highest Terrestrial Power .......... 80x (7mm eyepiece)
Highest Practical Power ........ 160x (3.5mm eyepiece)
Theoretical Maximum ............... 187x (3mm eyepiece)
Retractable dew shield
Lock knob for
focuser drawtube
Locking collar for 360°
rotatable focuser
PARTS OF THE AT80ED
Left coarse
focus knob
Fine
focus
knob
Focusing
scale on
focuser
drawtube
1.25”
eyepiece
adapter
1.25” eyepiece
lock knob
Dust cover
1.25” eyepiece
lock knob
Brass compression ring
Right
coarse
focus
knob
Mounting points for
optional finder
2” eyepiece
lock knob
2”
accessory
holder
Dust
cap
Tube ring
Hinged split
tube rings
Fine
focus
knob
Right
coarse
focus
knob
Locking collar for 360°
rotatable focuser
Removable
Vixen-style dovetail