Origin Shots

All surveys have to begin somewhere. The first station in a cave survey is called the origin. Most of the time, the origin is at the entrance of a cave, but it can be almost anywhere in the cave. It all depends on where you begin surveying. For example, if you started surveying at the back of the cave and surveyed out, the origin would be at the back to the cave. Basically, the Compiler treats the first station in the survey file or survey project as the origin.

The origin is important because it is used as the reference to all other stations in the cave. The Compiler set the location of the origin station to zero east, zero north and zero vertical. The location of every station and feature in the cave will be relative to this station. For example, if the elevation station CD21 is at -20 feet, this means that it is twenty feet below the origin.

You can force any station in a cave to be at a fixed location using the fixed station options. Usually, you will set a fixed location for the entrance station, which will also be the origin. However, since you can set a location for any station, you can effectively override the origin station. In this case, the origin station will appear at some location relative to the fixed station.