Spectra Precision Focus 30, User Manual

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Spectra Precision FOCUS 30 User Guide 61
4 Setup
Optical Plummet
1. Set up the instrument and level it over a ground mark so that the tripod height is
1.5 m (±0.1 m) (4.920 ft (±0.328 ft)), see
Figure 4-50
2. Note the position of the inner circle of the optical plummet in relation to the
ground mark.
3. Turn the instrument 200 grads (180 degrees).
4. Note the position of the inner circle of the optical plummet in relation to the
ground mark. If the inner circle of the optical plummet reticle moves in relation
to the ground mark, you must adjust the plummet reticle location.
5. Adjust out half of the error with the four adjustments screws on the optical
plummet.
6. Turn the instrument 200 grads (180 degrees).
7. If there is no movement between the inner circle of the optical plummet reticle
in relation to the ground mark, no further adjustment is needed.
C
Caution – When adjusting the optical plummet with the four adjustment screws it is impor-
tant that the screws are correctly adjusted. When one screw is adjusted the opposite
screw must be adjusted equally in the reverse direction, in order to keep the correct ten-
sion on the optics. Do not overtighten the screws, this might damage the optics.
Fig. 4-50 Optical plummet adjustment
Ground mark
Optical plummet reticle
4x adjustment screws