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Figure 3. Thread the extension cylinder onto the tripod by turning
the T-bar clockwise.
tube to insert until the O-ring seats inside the cylinder.
Then rotate the two black thumbscrews clockwise so
that they push the tube into the center of the cylinder. The
assembled finder scope should now appear as in Figure
6C.
3.
Now install the finder scope on the optical tube by sliding
the bracket foot into the dovetail shoe, as shown in
Figure 7. Secure the bracket with the thumbscrew on the
shoe.
Installing a Diagonal and Eyepiece
1.
To attach a diagonal, insert the diagonal's chrome barrel
into the focuser drawtube collar, then tighten the two
thumbscrews on the drawtube collar (Figure 8).
2.
Then insert the 25mm eyepiece into the diagonal and
secure it by lightly tightening the thumbscrew(s) on the
diagonal.
Your VersaGo GX 80 telescope is now completely assembled!
Before jumping right in and starting to use it, however, there
are a couple of things you should do first to prepare the tele-
scope for operation.
III. Getting Started
The next things to do are to align the finder scope with the
telescope and focus the finder scope.
Aligning the Finder Scope
A finder scope makes it easier to find the subject you want
to observe in the main telescope. That's because the finder
scope has a much wider field of view than that of the main
telescope. Before you use the finder scope, it must be pre-
cisely aligned with the telescope, so they both point to exactly
the same spot.
4
Extension
cylinder
T-bar
Figure 4
until tight.
Alignment is easiest to do in daylight, rather than at night under
the stars. First, insert the lowest-power (25mm) eyepiece into
the telescope's focuser. Then point the telescope at a discrete
object such as the top of a telephone pole or a street sign that
is at least a quarter-mile away. Move the telescope so the tar-
get object appears in the very center of the field of view when
you look into the eyepiece. Now look through the finder scope.
Is the object centered in the finder scope's field of view, i.e.,
on the crosshairs? If not, hopefully it will be visible somewhere
in the field of view, so only fine adjustment of the two black
nylon alignment screws will be needed. Otherwise you'll have
to make coarser adjustments to the alignment screws to redi-
rect the aim of the finder scope. Use the two alignment screws
to center the object on the crosshairs of the finder scope. Then
look again into the main telescope's eyepiece and see if it is
still centered there as well. If it isn't, repeat the entire process,
making sure not to move the main telescope while adjusting
the alignment of the finder scope. Finder scopes can come out
of alignment during transport of the telescope, so check the
alignment before each observing session.
Focusing the Finder Scope
If, when looking through the finder scope, you notice that
the images appear out of focus, you will need to refocus the
finder scope for your eyes. First loosen the lock ring located
behind the objective lens cell on the body of the finder scope
(see Figure 6C). Back the lock ring off by a few turns, for now.
Refocus the finder scope on a distant object by threading the
objective lens cell in or out of the finder scope body. Precise
focusing will be achieved by focusing the finder scope on a
bright star. Once the image appears sharp, retighten the lock
.
Thread the altazimuth mount onto the extension cylinder
Pointer
Mount
Extension
cylinder
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