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Eyepiece
1.25" collar
Star
diagonal
Figure 10.
Insert the eyepiece into the star diagonal and secure
it with the thumbscrew.
Figure 11.
The 1.25" adapter can be removed from the 2"
focuser, allowing use of an optional 2" diagonal and 2" eyepieces if
desired.
of motion – and you cannot turn the knob further – you should
reverse direction by 10 degrees or so, then release the Dec. lock
knob and move the telescope by hand back to about where it
was pointed before the slow-motion cable stopped turning. Now
you should be able to use the slow motion cable again for fine
pointing in either direction.
Tracking Celestial Objects
When you observe a celestial object through the telescope,
you'll see it drift slowly across the field of view. To keep it in the
field, assuming the equatorial mount is polar aligned, just turn
Drawtube
tension
thumbscrew
Focus
2"
wheel
1.25"
accessory
adapter
collar
2" accessory
collar
1.25"
adapter
Power switch
Red LED
Altitude
adjustment
knob
Tab
Figure 12.
Features of the EZ Finder II.
the R.A. slow-motion control cable counterclockwise to track.
The Dec. slow-motion control cable is not needed for tracking.
Objects will appear to move faster at higher magnifications,
because the field of view is narrower.
Optional Electronic Drive for Automatic Tracking
An optional DC electronic drive is available for the AstroView
102 EQ Refractor's equatorial mount. This battery-operated
drive provides automated, hands-free tracking. Objects will then
remain stationary in the field of view without any manual adjust-
ment of the R.A. slow-motion control cable.
Understanding the Setting Circles
The two setting circles on an equatorial mount enable you to
locate celestial objects by their "celestial coordinates" . Every
object resides in a specific location on the "celestial sphere" . That
location is denoted by two numbers: its right ascension (R.A.)
and declination (Dec.). In the same way, every location on Earth
can be described by its longitude and latitude. R.A. is similar to
longitude on Earth, and Dec. is similar to latitude. The R.A. and
Dec. values for celestial objects can be found in any star atlas
or online planetarium app.
On the AstroView 102 EQ Refractor's equatorial mount, the R.A.
setting circle is scaled in hours, from 1 through 24, with small
marks in between representing 10-minute increments (Figure
16). The numbers at the base of the setting circle scale apply to
the Northern Hemisphere while the numbers above them apply
to viewing in the Southern Hemisphere.
The Dec. setting circle is denoted in degrees, with each main
mark representing 10° increments (Figure 16). Values of Dec.
coordinates range from +90° to -90°. The 0° mark indicates
the celestial equator. For this mount, the number scale goes to
90 on either side of 0 – there are no (+) or (-) signs. When the
telescope is pointed north of the equator, actual values of Dec.
are negative.
For example, the coordinates for the Orion Nebula (M42) are:
R.A. 5h 35.4m Dec. -5° 27'
Azimuth
adjustment
knob
Battery cover
7
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