ORION TELESCOPES & BINOCULARS GoScope III User Manual

6
on the pan head with a DSLR camera, allowing quick switching
between landscape (horizontal) and portrait (vertical) camera
orientations.
The tripod also comes equipped with a geared center column,
which provides additional height for the scope when needed.
(See Figure 13.) To extend the column, rst loosen the center
column lock knob a half turn or so. Then pull the crank handle
outward and rotate it clockwise. When you reach the desired
height, retighten the lock knob. To lower the center column, loos-
en the lock knob then rotate the crank handle counterclockwise.
Eyepiece Selection
Magnication, or power, is determined by the focal length of
the telescope and the focal length of the eyepiece being used.
Therefore, by using eyepieces of different focal lengths, the
resultant magnication can be varied. It is quite common for an
observer to own ve or more eyepieces to access a wide range
of magnications. This allows the observer to choose the best
eyepiece to use depending on the object being viewed and
viewing conditions. Your GoScope III 70mm refractor comes
with 20mm and 9mm Kellner eyepieces, which will suffice nice-
ly to begin with. You can purchase additional eyepieces later if
you wish to have more magnication options.
Magnication is calculated as follows:
Telescope Focal Length (mm)
= Magnication
Eyepiece Focal Length (mm)
For example, the GoScope III 70mm has a focal length of
400mm, which when used with the supplied 20mm eyepiece
yields:
400 mm
= 20x
20 mm
The magnication provided by the 10mm eyepiece is:
400 mm
= 44x
9 mm
The maximum attainable magnication for a telescope is directly
related to how much light it can gather. The larger the aperture,
the more magnication is possible. In general, a gure of 50x per
inch of aperture is the maximum attainable for most telescopes.
Going beyond that will yield simply blurry, unsatisfactory views.
Your GoScope III 70mm has an aperture of 70mm, or 2.8 inches,
so the maximum magnication would be about 140x (2.8 x 50).
Figure 6. a) Attach the quick-release plate to the dovetail
mounting plate on the telescope. b) Slide the quick-release
plate into the pan head’s saddle by tilting it and then pressing
downward. c) Finally, close the lock lever to secure the telescope
on the pan head.
“
D
”
Ring
Dovetail
mounting
plate
Lock lever
in open
position
Lock lever in
locked position
Quick-
release
plate
Threaded
post
Figure 7. Curl the plastic strip and slide it into the open tube of
the nder scope bracket.
Clear plastic
strip
a
b
c

ORION TELESCOPES & BINOCULARS GoScope III Specifications

General

Brand	ORION TELESCOPES & BINOCULARS
Model	GoScope III
Category	Telescope
Language	English