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The C130 spotting scope focusing mechanism controls the position of the primary mirror which slides back and forth on the primary baffle
tube. Turn the focusing knob until the image is sharp. If the knob will not turn, the primary mirror has reached the end of its travel on the
focusing mechanism. Turn the knob in the opposite direction until the image is sharp. Once an image is in focus, turn the knob clockwise
to focus on a closer object and counterclockwise for a more distant object. A single turn of the focusing knob moves the primary mirror
only slightly. Therefore, it will take many turns to go from close focus (approximately 40 feet) to infinity. For astronomical viewing, out-
of-focus star images are very diffuse making them difficult, if not impossible, to see. If you turn the focus knob too quickly, you can go
right through focus without seeing the image. For best results, your first astronomical target should be a bright object (like the Moon) so
that the image is visible even when out of focus.
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To determine the magnification of your spotting scope, simply divide the focal length of the spotting scope by the focal length of the
eyepiece used. In equation format, the formula looks like this:
Focal Length of Spotting Scope
(mm)
Magnification
=
Focal Length of Eyepiece
(mm)
Let’s say, for example, you are using the 32mm Plossl eyepiece. To determine the magnification you simply divide the focal length of
your spotting scope (2000mm) by the focal length of the eyepiece, 32mm. Dividing 2000 by 32 yields a magnification of 63 power.
Although the power is variable, each instrument under average skies has a limit to the highest useful magnification. The general rule is that
60 power can be used for every inch of aperture. For example, the C130 is 5 inches in diameter. Multiplying 5 by 60 gives a maximum
useful magnification of 300 power. Although this is the maximum useful magnification, most observing is done in the range of 20 to 35
power for every inch of aperture which is 100 to 175 times for the C130 spotting scope.
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With the use of an optional photograghic T-adapter (#93635-A) and camera specific T-
ring, a 35mm camera can be attached to the rear cell of the spotting scope. To attach a
camera to your C130 Mak:
1.
Remove the erect image diagonal and eyepiece from the rear cell of the tube.
2.
Thread the T-Ring onto the T-Adapter.
3.
Mount your camera body onto the T-Ring the same as you would any other lens.
4.
Thread the T-Adapter onto the back of the C130 by rotating the slip ring clockwise
while holding the camera in the desired orientation (either vertical or horizontal).
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Model
52275
Optical Design
Maksutov-Cassegrain
Aperture (mm)
130
Focal Length (mm)
2000
Eyepiece
32mm (63x)
Angular Field of View (FOV°)
.83°
Linear FOV (ft. @ 1000 yds)
44ft
Eye Relief
22mm
Near Focus
40ft
Coating
Multi-Coated
Length
18 in
Weight
9.25 lbs
All specifications given with standard eyepiece and are subject to change without notice.
Figure 1-4 – Optional T-adapter and T-ring
attachment onto the rear cell.
