Total-station offset shot
The coordinates of a point the prism cannot sit on: from a shot beside it with left, right, in, or out offsets, or from an angle offset to the center of a tree or pole.
Experimental: not yet fully verified. How results are checked
The point is at northing 5,130.179 ft, easting 5,076.02 ft, 150.75 ft from the station on N 30°17'00.0" E.
- Easting
- Horizontal distance
- Azimuth
- Bearing
Provenance
- Computed by
- survey.cogo.offset-shot 1.0.0, core 0.1.0
- Model
- Distance offset: out moves along the line of sight and right at 90° to it. Angle offset: the center lies at the measured distance plus the radius, along the direction turned to the center (Ghilani & Wolf 2021, total-station field practice)
- Accuracy
- Exact for the geometry; an angle offset assumes the shot was taken to the side of a round object at the same distance as its face
- Notes
- 1 shown with the answer
- Cites
- Ghilani, C. D., and Wolf, P. R., Pearson, Elementary Surveying: An Introduction to Geomatics
Something look off?
How we got thisFormula, worked example, sources, and proof
Model: Distance offset: out moves along the line of sight and right at 90° to it. Angle offset: the center lies at the measured distance plus the radius, along the direction turned to the center (Ghilani & Wolf 2021, total-station field practice)
Accuracy: Exact for the geometry; an angle offset assumes the shot was taken to the side of a round object at the same distance as its face
Worked example: The center of a tree: 150.00 ft to its side, 0.75 ft radius. Source: add-survey-suite tree-center scenario. It is golden test vector v001, and every build checks the tool still gives its answer within its tolerance.
You enter
- Direction to the center
- N 30°17'00" E
- Direction to the prism
- N 30°00'00" E
- Horizontal distance
- 150 ft
- Station easting
- 5000 ft
- Station northing
- 5000 ft
- Radius
- 0.75 ft
You get
- Northing
- 5,130.179 ft
- Easting
- 5,076.02 ft
- Horizontal distance
- 150.75 ft
- Azimuth
- 30.283333°
- Bearing
- N 30°17'00.0" E
Review: Not yet independently reviewed by a licensed surveyor.
Last verified: 2026-09-23, when a maintainer last confirmed this tool's sources at the issuer. See the sources ledger.
Status: version 1.0.0, core 0.1.0. See this tool in the verification report.
Changes
- 2026-09-23, fixed: Survey tools cite Ghilani and Wolf's Elementary Surveying, 16th edition (2021), but their method notes said "Ghilani & Wolf 2018". The notes now give 2021, the edition cited. No results change. Changelog
Checked against: 6 golden test vectors (download the test vectors, each with its source and tolerance). See how results are checked and every source.
Sources
- Elementary Surveying: An Introduction to Geomatics, Ghilani, C. D., and Wolf, P. R., Pearson, 16th edition. Chapter 4 (curvature and refraction), chapter 6 (reducing slope distances), and the total-station chapters (two-face zenith observations and index error).
Experimental means this tool has not yet met the stable bar: at least 20 golden vectors, differential tests, and an independent worked example.