Orion APEX 9823, APEX 9825, APEX 9820 User Manual

INSTRUCTION MANUAL

Orion® Apex™

Maksutov-Cassegrain

Optical Tube Assemblies

#9820 Apex 90mm #9823 Apex 102mm #9825 Apex 127mm

™

Providing Exceptional Consumer Optical Products Since 1975

Customer Support [phone]
E-mail: [e-mail]

Corporate Offices [phone]

89 Hangar Way, Watsonville, CA 95076

IN 161 Rev. C 02/09

Eyepiece adapter

25mm Sirius
Plössl eyepiece

Finder scope
bracket

Correct-image
finder scope

Dovetail holder

45° correct-image
diagonal

Focus knob

Mounting block

Figure 1: The Apex Maksutov-Cassegrain optical tube assembly parts diagram. The Apex 102mm is shown,

but all models have similar components.

Welcome to a new world of adventure! Your Apex
Maksutov-Cassegrain (Mak-Cass) telescope is a
fine-quality instrument designed for both daytime
terrestrial viewing and nighttime stargazing.
Compact, portable, and easy to use, this versatile
scope will provide many hours of enjoyment for the
whole family.

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.

Meniscus
lens

These instructions will help you set up and prop­erly use and care for your telescope. Please read
them over thoroughly before getting started.

Parts List

Qty. Description
1 Optical tube assembly
1 25mm Sirius Plössl eyepiece
1 45° correct-image diagonal
1 Correct-image finder scope
1 Finder scope bracket
1 Soft carry case
1 Optical tube dust cover

2

Getting Started

The Apex telescopes come nearly fully assembled from the
factory. The optics have been installed and collimated, so you
should not have to make any adjustments to them. Open the
box and inspect the contents to make sure all of the parts
listed above are present. Refer to Figure 1 to see what the
parts look like, and how they will connect togther; the Apex
102mm is shown, but all models have similar components.

Please keep the original shipping box. In the unlikely event
you should need to ship the telescope back to Orion for war­ranty repair service, you should use the original packaging.
The box also makes a very good container for storing the tele­scope when it is not in use.

Spring-loaded

tensioner

Eyepiece end of
finder scope

Alignment thumb
screw (3)

Finder scope eyepiece

Figure 2: Insert the 6x20 finder scope into the bracket’s
rings so that it is oriented as shown.

Installing the Accessories

Apex 90mm:

To place the finder scope in the finder scope bracket, first
unthread the three alignment thumb screws on the bracket
until the screw ends are flush with the inside of the bracket’s
ring. Insert the finder scope into the bracket so that the eye­piece end of the finder scope (the end with the rubber
eyeguard) is closest to the bracket’s alignment thumb screws
(see Figure 2). Secure the finder scope in place by tightening
the three alignment thumbscrews.

Apex 102mm and 127mm:

To place the finder scope in the finder scope bracket, first
unthread the two black nylon alignment screws until the screw
ends are flush with the inside of the bracket’s cylinder. Place
the O-ring that comes on the base of the bracket over the
body of the finder scope until it seats into the slot on the mid­dle of the finder scope. Insert the eyepiece end (narrow end)
of the finder scope into the end of the bracket’s cylinder that
does not have the alignment screws, while pulling the spring­loaded tensioner on the bracket with your fingers (see Figure

3). Push the finder scope through the bracket until the O-ring
seats just inside the front opening of the bracket’s cylinder.
Now, release the tensioner and tighten the alignment screws
a couple of turns each to secure the finder scope in place.

Alignment thumb screws

Figure 3: To install the 6x26 finder scope in the finder
scope bracket, pull the spring-loaded tensioner while
inserting the eyepiece end of the finder scope into the
bracket.

All models:

Connect the finder scope bracket to the dovetail holder on the
optical tube with the thumb screw on the holder. Insert the 45°
diagonal into the eyepiece adapter and secure it with the
thumb screws on the eyepiece adapter. Insert an eyepiece
into the diagonal and tighten the thumb screws on the
diagonal.

Keep the dust cap over the front end of the telescope when it
is not in use. It is also a good idea to cover the eyepiece; use
the cover cap that came with it.

Mounting the Telescope on a Tripod

The Apex Maksutov-Cassegrain optical tube assemblies can
be mounted on any standard camera tripod that has a 1/4"-20
stud. The stud threads into the block on the underside of the
telescope’s optical tube (see Figure 4). Alternatively, the tele­scopes can be attached to an altazimuth or equatorial mount
equipped with a 1/4"-20 adapter. For the Apex 127mm, there
are several threaded holes in the mounting block; use the one
that will best balance the telescope on the tripod or mount.

1/4”-20 stud

Mounting block

O-ring

Figure 4: The
1/4”-20 stud on
standard camera
tripods will thread
into the mounting
block on the
underside of the
Apex telescopes.
The Orion Paragon
HD-F2 tripod
shown utilizes a
quick-release shoe
to connect the
telescope to the
tripod.

3