Appendix B: Setting Circles - Meade LX70 Series Instruction Manual

APPENDIX B:
Setting Circles
To use the setting circles to locate an object not
easily found by direct visual observation:
Insert a low-power eyepiece, such as a 26mm,
into the focuser assembly. Pick out a bright star
with which you are familiar (or is easily located)
that is in the area of the sky in which your target
object is located. Look up the R.A. coordinate of
the bright star, and also of the object you wish
to locate, in a star atlas or on the internet. Point
the telescope at the bright star. Then loosen the
R.A. setting circle lock knob (see Fig. 42) and
turn the R.A. setting circle to read the correct
R.A. coordinate of the bright star; lock the R.A.
setting circle lock knob to secure the setting
circle in place (If you are in the northern hemi-
sphere, use the top numbers on the RA setting
circle. If you are in the southern hemisphere use
the bottom numbers.). Next, adjust the DEC set-
ting circle by moving the setting circle ring until
Figure 42: RA setting circle and lock knob
the objects DEC coordinate is aligned with the 0
registration mark. If the procedure has been fol-
lowed carefully, the bright star should now be in
the center of the telescope eyepiece and setting
circles showing the bright star coordinates.
To locate another object, unlock the RA and
DEC locks and move the telescope so the RA
and DEC setting circle coordinates match the
target object. Then lock each axis and use the
slow motion controls to track the object.
If when using the setting circles to locate ob-
jects, you do not immediately see the object
you are seeking, try searching the adjacent sky
area. Start with the 26mm eyepiece when locat-
ing object since it has a wider field of view than
the 9mm. Because of its much wider field, the
viewfinder may be of significant assistance in
locating and centering objects, after the setting
circles have been used to locate the approxi-
mate position of the object.
RA Setting Circle RA Setting Circle
Lock Knob Lock Knob
RA Setting Circle RA Setting Circle
Figure 43: DEC setting circle
20 20
DEC Setting Circle DEC Setting Circle