
INSTRUCTION MANUAL
Orion®
Observer™ 70 EQ
#9882 Equatorial Refractor Telescope
Providing Exceptional Consumer Optical Products Since 1975
Customer Support (800) 676-1343
E-mail: support@telescope.com
Corporate Offices (831) 763-7000
89 Hangar Way, Watsonville, CA 95076
IN 211 Rev. B 02/09

Welcome to the exciting world of amateur astronomy. Your new Observer 70 EQ Refractor is a quality
optical instrument that will deliver countless hours of exciting stargazing, from magnified views of the
Moon, star clusters, and nebulas to glimpses of Jupiter’s moons and Saturn’s rings. The Observer 70
includes everything you need to go from box to backyard in less than half an hour.
These instructions will help you set up, use, and care for your new telescope.
Table of Contents
1. Unpacking........................ 3
2. Parts List......................... 3
3. Assembly ....................... 10
4. Getting Started ................... 11
5. Using Your Telescope .............. 15
6. Care and Maintenance ............. 18
7. Specifications .................... 18
1. Unpacking
The entire telescope system will arrive in one box. Be careful
unpacking the box since some of the contents are small and
easy to overlook. We recommend keeping the box and all
original packaging. In the event you need to ship the telescope
to another location, or return it to Orion for warranty repair,
having the proper packaging will help ensure that your telescope will survive the journey intact.
Warning: Never look directly at the Sun through
your telescope or its finder scope—even for an
instant—without a professionally made solar
filter that completely covers the front of the
instrument, or permanent eye damage could
result. Young children should use this telescope
only with adult supervision.
Make sure all the parts in the parts list are present. Familiarize
yourself with their features and compare them to the callouts
on Figures 1, 2, and 3 when possible. If anything appears to
be missing or broken, immediately call Orion Customer
Support (1-800-676-1343) for assistance.
2. Parts List
1 Optical tube assembly (1)
2 Tube Rings (6) (located on optical tube)
1 Equatorial mount (5)
2 Slow motion control cables (8,9)
3 Tripod legs (10) with attached accessory tray
bracket (11)
1 Accessory tray (11) with attachment screws
1 Counterweight shaft (26)
1 Counterweight (7)
1 EZ Finder II reflex sight (4)
1 EZ Finder II mounting bracket (17)
3 Tripod attachment screws with wingnuts and
washers (32)
3 Leg lock knobs (13)
1 Latitude adjustment T-bolt (30)
1 25mm Explorer II eyepiece (3)
1 10mm Explorer II eyepiece
1 Dust cover
1 90° Mirror star diagonal
3

Observer 70 Refractor
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Figure 1. Observer 70 EQ Components

The Basic Components of Your Telescope
Figure 1 shows the fully assembled Observer 70 EQ. All the major components of the telescope are described and numbered to
help you identify each part and understand its use. Refer back to this figure when assembling the telescope.
1
Optical tube
This is the main optical component of the telescope. The
glass lens at the front of the tube gathers incoming
light and focuses it by bending (or refracting) the light
rays. The tube assembly has several parts built into it,
which are shown and discussed in detail in the next
section.
2
90° mirror star diagonal
The diagonal contains a mirror that reflects the light gath-
ered through the optical tube to the eyepiece. The diagonal is angled to allow for viewing objects that are high
in the sky from a comfortable position.
3
25mm Explorer II eyepiece
The eyepiece is the part of the telescope that you actually
look through to see things. The focal length of the eyepiece and the telescope determines the magnifying
power of the telescope. Magnification is discussed in
more detail in the Using Your Telescope section.
4
EZ Finder II reflex sight
This is a special “finder” that helps you aim the telescope
and locate objects in the sky for viewing. The EZ Finder
II generates a red LED “dot” that shows where your
telescope is aimed. The use of the EZ Finder II is discussed in the Getting Started section.
5
Equatorial mount
This mount couples the optical tube (1) to the tripod. It also
serves to allow tracking of celestial objects with the
telescope when properly polar aligned. See the Aligning
the Equatorial Mount section for more details.
6
Tube Rings
These rings attach to the equatorial mount (5) and hold
the optical tube (1).
7
Counterweight
This counterweight will balance the optical tube (1) when it
is being aimed at celestial objects.
8
Right ascension slow-motion control cable
This cable, along with the declination slow-motion control
cable (9) is used to make small movements in right
ascension when aiming the telescope. Right ascension
is explained in the Aligning the Equatorial Mount section. This cable is also used to “track” stellar objects
and keep them in the field of view
9
Declination slow-motion cable
This cable, along with the right ascension slow-motion
control cable (8) is used to make small movements in
declination when aiming the telescope. Declination is
explained in the Aligning the Equatorial Mount section.
10
Tripod legs
These aluminum tripod legs support the telescope and
can extend from 27" to 50" long.
11
Accessory Tray
This tray is a convenient place for holding extra eyepieces
and other small pieces of equipment.
12
Accessory tray bracket
This bracket holds the accessory tray (11) to the tripod.
13
Leg lock knobs
These knobs lock the tripod legs into place. Loosen them
to lengthen or shorten the tripod legs. Tighten them
once you have the leg at the desired length. Be certain
that all three tripod legs are equally extended to assure
your telescope is level.
5

Observer 70 Telescope Tube
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Figure 2a. Optical tube components
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Figure 2b. Observer 70 focuser detail