Spectra Precision Survey Pro v4.6 Ranger User Manual - Manual (Page 121)

Mapping Plane Scale Factor
111
Combined Scale Factor
You should select Use a single combined scale
factor option when using a single combined
scale factor to reduce all your total station
measurements. The scale factor might be
provided for you, in which case you simply
enter the value in the Combined Factor field and
tap to return to the Job > Settings > Surveying
screen, otherwise you can calculate the
combined scale factor as described below.
A map zone must be set up before a combined
scale factor can be calculated. To configure a
map zone, tap the bottom button to open the
Select Coordinate System screen. This button is labeled Change Map
Zone if a map zone is already configured or Set Map Zone if a map
zone is not yet configured. Configuring a map zone is described in the
Projection Mode section of this manual, starting on Page 222.
Tap Calculate Scale to open the Scale Calculator wizard, which is used
to compute the combined scale factor based on the current map zone.
If a map zone is not currently configured, the Select Coordinate
System screen will open first where you can set one up.
Enter a reference point in the Select Point field
and tap Calc. Scale>.