Raymarine LIGHTHOUSE 4, Operation Instructions Manual

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SideVision™ overview
SideVision™ transducers are side looking transducers that produce 2
wide-angle side-to-side beams, each with a thin fore-to-aft beam to build up a
detailed underwater view as your vessel moves forward.. The coverage of
the SideVision™ beams is an area to both side of your vessel.
SideVision™ beams
The transducers send pulses of sound waves into the water on each side
of your vessel, and records the sound waves that are reflected off objects
suspended in the water column and the bottom,, known as sonar returns.
The sonar image is constructed line-by-line, similar to the way a television
picture is composed of many horizontal lines. Each successive ping from
the transducer adds a new line of image data to the top of your display.
Each new line shows sonar returns from both the port and starboard sides of
your vessel. As new lines are added with each successive ping, older data
gradually scrolls down the display, building up a detailed image of the water
column and bottom to the sides of your vessel. If your vessel maintains the
same bearing and speed for a period of time, you can interpret the image as
a plan of the bottom along your vessel’s course. SideVision™ is effective at
lower vessel speeds.
Note:
SideVision™ does not provide direct depth readings. The scale shown
across the top of the image indicates the distance of features from your
vessel.
SideVision™ screen interpretation
1. Range scale — The range scale indicates distance (range) to port and
starboard from your vessel.
2. Water — Using the default color palette black indicates no sonar returns
i.e.: clear water.
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