Spectra Precision ProMark 800 Reference Manual - Manual (Page 58)

46
Precise Surveying - Field Applications & Concepts
2. Contrary to Stop & Go survey, there is no occupation time
on a particular point. Data logging should be started at the
beginning of the line and stopped at the end.
3. Log interval. With some field software applications, such
as FAST Survey, the log interval can only be equal to the
raw data recording rate, meaning that the line is
necessarily surveyed in time mode.
With some others, more dedicated to post-processed
surveys (such as ProMark Field), the log interval is distinct
from the raw data recording rate. With this field
application, you can log your lines either in distance or
time mode and you set the log interval independently.
In distance mode, a new marker is created every x meters.
In time mode, a new marker is created every x seconds,
where ”x” is the log interval.
While you are moving along the line, the rover inserts new
markers into the logged raw data file according to the
chosen log interval. Each marker is named as a point. The
name includes a numeral suffix that is automatically
incremented for each new logged marker. You must take
care however to use a log interval that is compatible with
the raw data recording rate:
In time mode:
log interval (s) >2 x raw data recording rate (s)
In distance mode:
log interval (m) > 2 x moving speed (m/s) x raw data recording rate (s)
4. Number of lines in a single file. Some field applications,
such as FAST Survey, allow you to log a single line into a
raw data file. Some others, like ProMark Field, allow you
to enter several start/stop markers in the same file
meaning that several lines can be logged in the same file.
Choosing a Location for the Base
The location of the base is fundamental for the success of
your survey. Whether you are in post-processing or real-time
mode and your receivers are single-, dual- or multi-frequency,
remember the rover position will always be computed relative
to the base position. Any inaccuracy in the base position will
inevitably be transferred to the position computed by the
rover.
When using base data from a third-party reference station or
from a network of reference stations, making sure the base
has been properly installed is not your responsibility. On the