Adjusting the 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 illustration below.

  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 reticule moves in relation to the ground mark, you must adjust the plummet reticule 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.

CAUTION – When adjusting the optical plummet with the four adjustment screws it is important 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 tension on the optics. Do not over tighten the screws, this might damage the optics.

1 Optical plummet Ground mark reticule 4x Adjustment screws 2 Ground mark