Targets and prisms
A prism is used together with an EDM for accurate range measurements. The targets are used together with a theodolite for aiming the instrument towards a point on the ground over which the target is placed (usually with plumb).
A prism is used together with an EDM for accurate range measurements. The targets are used together with a theodolite for aiming the instrument towards a point on the ground over which the target is placed (usually with plumb).