YSI Level Scout - Manual (Page 30)

Playback remembers the last display type, file type, and file name used and restores them on restart. See the Data Scout Advanced
Operations Manual for a complete description of all Playback functions. The Convert functions of Playback are described briefly
below.
3.4.2 COMPENSATE ABSOLUTE PRESSURES WITH BAROMETER
I f using a Absolute Level Scout, Playback can merge data collected from a BaroScout and Level Scout to compensate the Level Scout’s
data for changes in barometric pressure during the test. To correct for barometric pressure changes, select Uncompensate the Data
Per Barometer under the Convert menu. Selecting this function opens a Convert window (figure 3.35).
Figure 3.35
The default input file to be converted is the currently opened file. This file’s name appears in the Original file frame in the Convert
window. Use that frame’s Browse button to choose a different file name. Use the View/Edit button to view or edit the contents of
the selected file.
The Barometer (Reference) Data File frame (Barometer frame) must be populated with the name of the file containing absolute
barometric reference data. Use the Browse button to select the appropriate data file extracted from an BaroScout. This file should
have a date/time profile close to (the Original file to be compensated.
The default output file name in the New (Converted) Data File and Conversion Options frame is automatically set to the file name
in the Original frame, but with a version string “(v)” added to it, where v is a version number. This makes the new file name unique.
In this example, there were no previous versions of that file, so version “(1)” was added to the name.
Since the Original file contains data from only one level transducer, there is a single Comp check box (pre-checked) in the New
frame, plus a single corresponding Elevation text box. The elevation box is normally blank (which defaults to 0 inches). However,
any integer value may be entered (positive or negative) in inches (in), feet (ft), meters (m), or centimeters (cm). For example,
manually edit this box to indicate that the reference BaroScout is located 1 foot above the surface of the water that contains the
submerged level transducer to be compensated by entering 1 ft.
Since the date/time profiles of the two input files nearly match, but not quite perfectly, a special time tolerance for barometer
readings of 10 minutes has been set in this example(see Tolerance frame in bottom right corner of the window). This tolerance is
sufficient to allow for the date/time misalignment of the two files. If the tolerance was set to zero, then some compensated values in
the New file might be replaced with the error string **nobaro** instead of numeric converted values because the required barometer
reading was missing at the beginning or end of the file without an exact time correlation. With a tolerance larger than zero, the
“closest” barometer reading available will still be used as an estimate.
When the Convert button is clicked, this program converts every absolute pressure sample in the uncompensated Original file, using
the “closest” reference source of absolute pressure data in the Barometer file, and writes the New file. The conversion equations used
are simple and straight forward, and are described fully in the Data Scout Advanced Operations Manual. If conversion is successful, a
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