CST/BERGER CST202, Instruction Manual

Page: 18 / 117

13
（
5
）
Centering the instrument with optical plummet
：
Adjust the eyepiece of the optical plummet telescope to the user’s eyesight.
Move the instrument by loosening adjusting screw. Coincide image of the
point on the ground with the center mark of the optical plummet telescope.
Carefully move the instrument in order to make it steady.
Caution: don’t rotate the
instrument on the tripod, in order
to decrease the excursion of the
bubble.
（
6
）
Leveling the instrument accurately
Follow the step 4, until you rotate the
instrument and the bubble always in center. Tighten the centering screw.
7
．
FOCUSSING AND TARGET SIGHTING
CAUTION
：
z
When sighting the target, strong light shining directly into the objective
lens may cause the instrument to malfunction. Protect the objective
lens from direct light by attaching the lens cap when not in use.
z
Observe the same point of the reticle when the telescope face is
changed.
（
1
）
Focus on the reticle: look through the telescope eyepiece at a bright and
featureless background. Turn the eyepiece screw clockwise, then
counterclockwise little by little until just before the reticle image becomes
focused. Using these procedures, frequent reticle refocusing is not necessary
since your eye is focused at infinity.
（
2
）
Sight the target: loosen the vertical and horizontal clamps, then use the peep
sight to bring the target into the field of view. Tighten both clamps.
（
3
）
Focus on the target: turn the telescope focusing ring to focus on the target.
Turn the vertical and horizontal fine motion screws to align the target with
the reticle. The last adjustment of each fine motion screw should be in the
clockwise direction.
（
4
）
Readjust the focus until there is no parallax: readjust the focus with the
focusing ring until there is no parallax between the target image and the
reticle.
测站点
中心标记
Observation
Center mark