Astro-Tech AT65EDQ Quick Start Manual

astro-tech A T 65EDQ
Thank you for choosing this Astro-Tech AT65EDQ ED
apochromatic quadruplet astrograph.
Its 420mm f/6.5 apochromatic triplet objective lens uses
an FPL-53 ED (Extra-low Dispersion glass) element to provide
very wide field images that are virtually color-free. A separate
ED singlet field flattening lens assures that those images
will be sharply focused from one edge of the field to the
other. This eliminates the need for the separate external
field flattener that is needed for the best images with most
PARTS OF THE AT65Q
Lock knob for 360°
camera rotation
Hole S
Fine
focus
knob
Coarse
Lock knob for focuser
focus
drawtube (typically
knob
threaded into the hole
marked "S" above for
shipping purposes)
Astro-Tech AT65EDQ Apochromatic Quadruplet ED Refractor Specifications
Aperture ................................................. 65mm (2.56")
Focal Length .................................................... 420mm
Focal Ratio ............................................................ f/6.5
Optical System ...... apochromatic triplet objective with
FPL-53 ED element, plus singlet ED field flattener
Optical Coatings ............................... fully multicoated
Resolving Power
(Dawes' Limit)
Visual Limiting Magnitude ................. 11.6 maximum
Light Grasp
(versus the eye)
Image Circle ....................................................... 44mm
Focuser ........................ dual-speed 2" rack and pinion
with 10:1 reduction ratio fine focus;
360° rotating camera angle adjuster;
and 1.25" and 2" compression ring accessory holders
Your Astro-Tech AT65EDQ astrograph has a 2" focuser with a
non-marring rotating 2" brass compression ring accessory holder
for use with 2" imaging accessories. Also supplied is a 1.25" brass
compression ring adapter for use with 1.25" accessories.
In addition to its primary job of low power wide field imaging,
your AT65EDQ is also usable for day and night viewing, simply
by adding a 1.25" star diagonal and eyepiece (most 2" diagonals
will not be able to reach an infinity focus with the AT65EDQ).
Almost any brand and focal length of 1.25" eyepiece can be used,
Lock knob for Lock knob for
finder bracket retractable dew
shield
Vixen-style
dovetail
.......... 1.78 arc seconds
...................................... 86x
from Astronomy Technologies
other fast focal ratio astrographic refractors. At its low price,
we believe you'll find that the wide field imaging performance
of your AT65EDQ is little short of astonishing.
This instruction sheet will provide you with information on
how to get the most out of your new astrograph, and how to
properly maintain your AT65EDQ so it can give you a lifetime
of imaging enjoyment.
Please familiarize yourself with your telescope's parts and
functions before operating it for the first time.
Dew shield
Mounting bracket
for optional finder
Retractable dew shield
Tube rings
1.25" compression
ring accessory
adapter
1.25" accessory
lock knob
Dust cover
Focuser Travel ....................................... 2.44" (62mm)
with millimeter scale on drawtube for repeatable focus
Back Focus
Dew Shield ............................... retractable, 88mm o.d.
Objective Lens Cover ............................ slip-on metal
Finder Bracket .................. Vixen-style mounting shoe
Tube Rings ....................... dual 80mm i. d. split hinged
tube rings with separate Vixen-style dovetail
Tube Diameter ........................................... 80mm o. d.
Tube Length
Tube Length
(1.25" adapter adds 10mm to either length above)
Weight ............................................ 4.75 lbs. (2.16 kg);
from a 40mm focal length for the widest field and lowest possible
magnification (10.5x) to a 3mm (140x) for high power use.
Occasionally, one individual eyepiece or another may not reach a
sharp focus, so some experimentation may be called for.
A word of caution: The ED singlet field flattener lens is at the
rear of the optical tube, just in front of the focuser. Do not insert a
Barlow lens, or any other long accessory, directly into the focuser
drawtube, as this may contact and scratch the field flattener.
Photographically, the 420mm focal length of your AT65EDQ
Focusing
scale on
focuser
drawtube
Left coarse
focus knob
2" compression
ring accessory
adapter
........................ 110mm
(without 1.25" adapter)
............... 13" (330mm)
(dew shield retracted)
......... 14.25" (362mm)
(dew shield extended)
5.65 lbs. (2.57 kg) with rings and dovetail
Dew
shield
lock
knob
Fine
focus
knob
Right
coarse
focus
knob
2" accessory
lock knobs