Formulas
The instrument calculates the slope distance, horizontal distance, height difference in accordance with the following formulas:
Earth curvature (1/R) and mean refraction coefficient (k) are automatically taken into account when calculating the horizontal distance and height difference. The calculated horizontal distance relates to the station height and not to the reflector height.
Reflector types: The reduction formulas are valid for measurements to all reflector types
• To prisms
• To reflector tape
• Reflectorless measurements
Formulas
The instrument calculates the slope distance, horizontal distance, height difference in accordance with the following formulas:
Earth curvature (1/R) and mean refraction coefficient (k) are automatically taken into account when calculating the horizontal distance and height difference. The calculated horizontal distance relates to the station height and not to the reflector height.
Distance measuring program Averaging: In the distance measuring program Averaging, the following values are displayed
D Slope distance as arithmetic mean of all measurements
s Standard deviation of a single measurement
n Number of measurements
These values are calculated as follows: 
