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This is a relatively short module that provides an introductory treatment of how we reduce observations for use in a network adjustment. It includes:
  • An explanation of why pre-processing and the reductions of observations are needed
  • An overview of different reductions of observations including meteorological, gravimetric and geometric reductions
  • A detailed treatment of how to reduce distances from 3D space to the ellipsoid (using elevations)
  • An introduction to reductions and tools for reducing ellipsoidal distances to the mapping plane, e.g. the Universal Transverse Mercator (UTM) grid system
  • Some implementation notes and intuition building

My own notes

I’m still assuming that you’re building your own “perfect set of notes” as you go through this material – to make sure you have a succinct reference to help you be efficient on a test or in your future work. So, I’m sharing my own notes here with you to help with that.

The self-assessment problems

My usual practice in a course like this is to share some problems with you so you can assess your understanding of the material. These are embedded after the lessons below.

So, dig into these problems either after you’ve finished looking at the material or as you go. Hustle to figure out the answers. Leave no stone unturned. Get help if you need it. Like the notes, I’m going to assume you’re building the “perfect set of reference problems” to help you be efficient in a test or to look back at in practice.

If you’re taking this course from me as part of a university class then these are a great way to study. I can’t ask exactly the same questions on a test, of course, but I do generally design the problems in a way that you can expect to do as well in the formal assessments as you can do on these self-assessment questions.

And there’s also a lab that integrates quite closely with this material. (Stay tuned for the link.) I recommend doing this as you go through this module.

Okay, now get started by clicking through the lessons below!