North
South
North
South
Diunal motion
Diunal motion
Eas
t
W
est
No
rth
Sou
th
★
・
・
・
・
・
W
es
t
Ea
st
No
rth
So
uth
★
・
・
・
・
・
Ea
st
W
es
t
So
uth
No
rth
★
・
・
・
・
・
(Inverted View)
(Erect View)
(Mirror-Reverse View)
Look for east
in the sky
E
W
S
N
E
W
S
N
E
W
S
N
E
W
S
N
★
↑
★
↑
★
↑
★
↑
★
★
↑
☆
★
☆
↓
★
R.A.axis
R.A.axis
N.C.P
N.C.P
Move to low the altitude.
East side
of the sky
East side
of the sky
Move to high the altitude.
East
East
Telescope's
motion
Telescope's motion
Chapter 5 APPLICATION
3
lign the Mount in the direction of Altitude.
Choose a bright star
near celestial equator in east but not too low, and put it in the filed of view of the eyepiece. Turn off the power
switch of the mount momentarily while looking into the eyepiece to see in which direction the star moves. Confirm the west and rotate
the eyepiece so that one of the cross hairs is parallel to the east-west direction in the field of view.
The figure shows the directions of north, south, east and west in the eyepiece according to a type of your telescope with or without a star diagonal.
The following descriptions are based on a telescope without a star diagonal. Drive the mount at sidereal rate and look into the eyepiece to monitor
a drift motion of the star in the north-south direction.
If the star drifts south (i.e. It moves toward the lower left apparently due to inverted view), move the mount to low in altitude.
If the star drifts north (i.e. It moves toward the upper right apparently due to inverted view), move the mount to high in altitude.
Adjust the mount with the altitude adjustment bolts. Make appropriate adjustments to the polar axis to eliminate the drift.
67