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Level Book / Booking
Book field levelling observations digitally, compute reduced levels, identify change points, and verify the arithmetic with professional level-book checks.
Digital Field Book
Start with a known benchmark RL. Enter one staff reading per row. The calculator uses BS → IS → FS sequencing and treats an FS followed by a BS on the same point as a change point.
Starting Benchmark
Booking Settings
Closing RL enables an independent closing error and proportional correction preview.
Staff Readings
| Obs. | Point | BS | IS | FS | Remark | Remove |
|---|---|---|---|---|---|---|
| 1 | ||||||
| 2 | ||||||
| 3 | ||||||
| 4 | ||||||
| 5 |
For a change point: book the FS before moving the level, then book the BS after moving it against the same CP point name.
Enter the known starting RL and field observations, then calculate.
Run Summary
Use the computed level book to review setups, rises/falls, closure and final coordinates of the levelling run.
Calculate the level book first.
Level Book Reference
Standard field-book conventions used by the calculator.
Height of InstrumentHI = RL + BS
RL = HI − staff reading
RL = HI − staff reading
Rise & FallRise = previous reading − current reading
Fall = current reading − previous reading
Fall = current reading − previous reading
HI arithmetic checkΣBS − ΣFS = Last RL − First RL
Rise/Fall checkΣRise − ΣFall = Last RL − First RL
Change pointFS before instrument move + BS after move on the same physical point.
Closing errorClosing error = computed closing RL − known closing RL.
Booking rule: An IS does not establish a new HI. Every new instrument setup starts with a BS, and the BS should be observed on the same change point that received the preceding FS.