Automatic Differential Leveling (Height of Instrument Method)
1️⃣ Enter the number of turning points and the known elevation of BM1 (benchmark).
2️⃣ Click Generate Input Table and enter BS / FS readings
(leave FS at BM1 and BS at BM2 blank).
3️⃣ Click Compute HI and Elevations to see the table and full step-by-step solutions.