6
with a red LED light is ideal. Beware, too, that nearby porch,
streetlights, and car headlights will ruin your night vision.
Eyepiece Selection
Magnification, 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 magnification can be varied. It is quite common for
an observer to own five or more eyepieces to access a wide
range of magnifications. This allows the observer to choose
the best eyepiece to use depending on the object being
viewed and viewing conditions. Your SpaceProbe II 76mm
reflector comes with 25mm (N) and 10mm (O) Kellner eye-
pieces, which will suffice nicely to begin with. You can pur-
chase additional eyepieces later if you wish to have more
magnification options.
Magnification is calculated as follows:
Telescope Focal Length (mm) / Eyepiece Focal Length
(mm) = Magnification
For example, the SpaceProbe II 76mm reflector has a focal
length of 700mm, which when used with the supplied 25mm
eyepiece yields:
700mm / 25mm = 28x
The magnification provided by the 10mm eyepiece is:
700mm / 10mm = 70x
Figure 6.
Thread the accessory tray onto the tripod leg brace;
the screw on the underside of the tray threads into the socket in the
center of the brace.
Figure 8.
Installing the optical tube on the mount.
a) Slide the micro-motion rod into the metal receptacle. b) Place the altitude castings on
the optical tube in the grooves of the yoke.
c
)
Install the yoke knobs.
Turn to tighten
Figure 7. The
assembled altaz-
imuth mount and
tripod.
a.
b.
c.
Micro-motion rod
Yoke Mount
Yoke Knob
Altitude casting
Groove
Receptacle
Grooves
