Magellan MobileMapper - GPS Software User Manual page 23

Logging screen
The Logging screen
also displays the dis-
tance traveled since
you started logging the
line feature, the num-
ber of satellites cur-
rently received and the
current value of PDOP
(see also page 28).
Two options are then prompted:
By Time: Select this option when you want to log a new
GPS position at regular intervals of time regardless of
the distance traveled since the last position logged.
After highlighting this option, press ENTER, choose a
time interval from the list and press ENTER. This
takes you back to the Logging screen where you can
see the list of attributes pertaining to the feature.
By Distance: Select this option when you want to log a
new GPS position only after you have moved by a cer-
tain distance since the last position logged. After high-
lighting this option, press ENTER, choose a distance
interval from the list and press ENTER. This takes you
back to the Logging screen where you can see the list
of attributes pertaining to the feature.
- As with a point feature, describe the feature by
describing the different attributes pertaining to the
feature
- When the description is finished, you can start walking
along the line feature
- When you arrive at the end of the line feature, with
MobileMapper Pro still displaying the Logging screen,
highlight the Close field at the bottom of the screen
and press ENTER to stop logging the feature.
The receiver determines the length of a line feature by
estimating the distance between successive points on the
line feature with the assumption that each point is on a
sphere of average Earth radius. The elevations of the
points are not factored into the equation. Thus the
receiver calculates the spherical distance rather than the
horizontal or slope distance between the successive posi-
tions.
15