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Operation
SeaBat Sonar UI - User Manual
Figure 4-14
Custom checkbox ticked to set the number of beams
4.3.1.3 Equi-Distant
Equi-Distant gives equally spaced soundings across the entire swath
using the maximum number of beams.
The spacing between the beams is equidistant. With Equi-Distant the
spacing is modified to maintain an equal horizontal distance between
soundings on the seafloor assuming a flat bottom.
It is recommended that Equi-Distant be used for general survey
applications where the requirement to achieve a specific number of
sounding per cell in the across-track is critical, or where the seafloor is
generally flat.
In extreme conditions, using Equi-Distant over complex structures can
cause magnified artifacts due to the large overlap between beams
towards the edge of the sector. When the ‘custom’ checkbox is selected
the number of beams can be set with the slider
Figure 4-15
Custom checkbox ticked to set the number of beams
The spacing distance between de beams can be set when additional to
the custom checkbox the ‘Constant spacing’ checkbox is selected.
When the constant spacing checkbox is enabled the shape of the bottom
is followed. With the ‘Maintain swath coverage’ checkbox it is possible to
specify what will happen when there are to less beams to maintain the
specified spacing. By enabling the ‘Maintain swath coverage’ checkbox
the spacing becomes the normal Equi-distant spacing mode. When the
‘Maintain swath coverage’ checkbox is not selected the specified spacing
is maintained but the coverage will be reduced when there are to less
beams to maintain the spacing.
4.3.1.4 Flexmode
Flexmode gives a combination of a high density of beams on and around
the object location and a reduced density of soundings for the rest of the
swath.
