Temporary adjustments :

•  Temporary adjustments are the adjustments which are required to be made at each setting of instrument before taking observations.

•  Following five temporary adjustments are required

1. Setting up

2. Centering

3. Levelling

4. Focusing the eye-piece

5. Focusing the objective

Permanent adjustments :

1. Horizontal axis should be perpendicular to vertical axis. Furthermore, vertical circle should also be perpendicular to horizontal axis.

2. The axis of plate bubble tube should be perpendicular to vertical axis.

3. The line of sight should be perpendicular to vertical axis.

4. When the telescope is horizontal and the altitude bubble is in center, the reading in vertical circle should be zero.