Using UTM Convergence

This option enables the use of a UTM convergence angle. Convergence is the angular difference between True North and UTM Grid North. Enabling this option rotates the cave so it is aligned with UTM Grid North, which may not be True North. This option should only be used if you are plotting a cave on a topo map that uses the UTM coordinate system. It should not be used with programs such as Google Earth, which aligns to True North.  For more information refer to the chapter on Convergence.