LISST - 25 User’s Guide
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Appendix A: Data File Formats
The raw data offloaded from the LISST-25X is in a binary format. This format is designed to be
compatible with the earlier version LISST-25. Because the LISST-25X has two size classes two
separate lines of data are stored in the LISST-25 format. This causes the strange plotting behaviour
in the LISST-25.EXE program. Below is the binary file format and the processed ASCII file
formats.
Binary Datafile format
Each sample consists of the following values
Date = Year*10000 + Month*100 + Day
Time = Hour*10000 + Minute*100 + Seconds
Vol = Full Range Volume Concentation * 1000
Size = Full Range Sauter Mean Diameter *1000
Tau = Optical transmission *1000
Vol_sub = >63 micron Range Volume Concentation * 1000
Size_sub = >63 micron Range Sauter Mean Diameter *1000
Depth = depth in meters*100
The values are stored in the following order using the specified number of bytes.
Date (4 bytes), Time (4 bytes), Vol (4 bytes), Size (4 bytes), Tau (2 bytes)
Date (4 bytes), Time (4 bytes), Vol_sub (4 bytes), Size_sub (4 bytes), Depth (2 bytes)
Processed ASCII Datafile format
The files processed by the LISST-25.EXE software will have the following format. Each
sample will be stored as two lines having the exact date and time. The first row will contain
the following: Date, Time, Full Range Volume concentration in micro-liters per liter (
µ
l/l),
Full Range Sauter Mean Diameter (SMD) in microns, and the Optical transmission. The
second row will contain the following values: Date, Time, >63 micron Range Volume
concentration in micro-liters per liter (
µ
l/l), >63 Range Sauter Mean Diameter (SMD) in
microns, and the Depth in meters. The format of the date and time is selectable within the
LISST-25 program.
