Vixen Sphinx SXP - Manual (Page 79)

Guide Star
Field of View
Guide Star
Field of View
Chapter 5 APPLICATION
CAUTION
The settings are defaulted to “RA: 0” and “DEC: 0”
North
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2
3
Backlash Compensation
Backlash is a momentary stoppage of the tracking motion of the mount that occurs when the motor gears reverse their rotation. Backlash
does not occur while the mount moves at a constant speed as the gears keep contact with each other. Backlash may occur when the
telescope is moved with the direction keys manually.
The backlash compensation provides a reduced time lag at the point of reversed motion where the gears lose the contact. It gives smoother
rotation of the gears on the mount.
Backlash compensation is not compatible with the PEC. Cancel using the PEC when you choose this option.
Precisely polar align the mount.
In SCOPE MODE , choose the motor speed to be set approximately between 1.2x and
4.0x with the or zoom key with looking at the right corner of the information bar on
the bottom of the screen.
Confirm the amount of backlash in the direction of R.A as follows. Center the 1st-
magnitude star in the filed of view of your eyepiece and watch how the star moves while
pressing the direction key. Press the direction key until the star begins to move.
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5
Press the direction key to watch how the star moves in the field of view.
If there is a time lag and the star does not begin to move instantly toward the direction you press, a value for the backlash compensation is
set too small (weak) or set to "0".
On the contrary, if the star begins to move quickly and becomes larger at the same time you press, a value for the backlash compensation
is set too large (strong).
Confirm the amount of backlash in the direction of DEC in the same way with the • direction keys.
Checking the Backlash
It is convenient to use a bright 1st-magnitude star in order to check a backlash amount for compensation.
Celestial Pole
North
Celestial Pole
Polar Axis Polar Axis
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