Triton Isis - Manual (Page 136)

June 2004 Isis® Sonar User's Manual, Volume1 122
Units
(radio buttons) Choices are Off, Time (in milliseconds), or Distance.
Time normally is used for subbottom channels.
Distance normally is in meters and normally is used
for side-scan channels. Select Off if depth correction,
delay and duration will not be used.
If units are meters, the distance is calculated based
on the Sound Velocity in water you specify. See
6.6
‘Sound Velocity (Record/Playback)’ .
Start Point Specified
as
(radio buttons) Choose to apply a delay or a depth correction for
towfish. Delay removes a constant amount of signal
regardless of towfish depth. Depth forces the zero
mark (top or left of the display) to be at a specific level
(reference depth) in the water column and adds or
subtracts time/distance to the pulse depending on the
towfish depth.
Reference Depth
(slider bar) If Delay was selected in Start Point specified as,
use this slider bar to specify the amount of time or
distance to wait after the outgoing pulse starts before
displaying data. If Depth was selected in Start Point
specified as, use the slider bar to specify the
Reference Depth that will be the zero mark of the
display. With a delay or depth correction applied, Isis
will still track the bottom
(10.7.2 ‘Bottom Track
and TVG’ ).
Duration
(slider bar) With the Duration slider bar, set the time or distance
over which Isis will record the return for each pulse.
Duration can be applied with either depth correction
or delay.
OK and Cancel Clicking OK applies your settings to one or all
channels, depending on which radio button you
selected in Apply Settings to (see above). Cancel
exits the dialog box without changing any values.
Chapter 8: Using the View Menu