All posts by Charles D. Ghilani
Transformation of Observations Part 2
In my previous article in the September issue, I demonstrate one method of taking conventional/optical observations and converting them into GNSS baseline vectors. Here I demonstrate how to create a map projection system that is near the ground, and thus on the surface we survey. These map projections are commonly referred to as low-distortion projections;...
Transformation of Observations
Educate: Where Theory Meets Practice In previous articles I’ve discussed the reduction of conventional surveying observations to their geodetic equivalents. This article presents how these observations can be reduced to simple vector components that match GNSS surveyed baseline vectors. Unfortunately this transformation of conventional observations to GNSS baseline vectors involves three-dimensional rotations, so the mathematics will increase....
Geodetic Observations, Part 3
Types of Distances for Geodetic Observations This article explores the various types of distances that are often listed on GNSS adjustment reports; for related articles on the difference between geodetic and observed azimuths and angles, see “Where Theory Meets Practice” in Professional Surveyor’s March and May 2014, issues. Slope (slant) distances (S) observed on the...
