A telescope mounted on trunnions can be aligned vertically with the target object, while the whole upper section rotates for horizontal alignment.
The whole upper section rotates for horizontal alignment. A telescope mounted on trunnions is aligned vertically with the target object.
A telescope mounted on trunnions is aligned vertically with the target object. The whole upper section rotates for horizontal alignment.
A telescope mounted on trunnions is aligned vertically with the target object. The whole upper section rotates for horizontal alignment.