"SB" wrote in message
...
I'm going to stick my neck out and ask a very newbie type question. Rodney
mentioned reading "True" rather than "Magnetic." I've puzzled for a while
now over why we would use "True" at all. I know... I should know...but I
don't.
The compass is obviously "Magnetic" and it would be used for taking
bearings
while under way. That data is then transferred to a paper chart that has a
compass rose with a magnetic measurement in it.
In short, when would one use the "True" measurement on a chart, when
reporting ones position to another, in a electronic charting program or
any
other occasion?

The GPS, when moving, points to the true geographic north, while a compass
points to the magnetic north. These are not the same. The magnetic north is
a few degrees off, depending on time and where you are. A good chart will
show this magnetic variance in the compass rose printed on the chart.

Meindert