Raymarine c125, Installation And Operation Instructions Manual

Page: 266 / 464

Interpreting SideVision™ images
The following illustration shows how SideVision™ images on your multifunction display are related to the
water column and sea floor to the sides of your vessel.
Interpreting SideVision images
SideVision™ images are constructed line-by-line,
similar to the way a television picture is composed
of many horizontal lines. Each successive ping
from the
SideVision™ 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
sea floor 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
sea floor along your vessel’s course.
The illustration also identifies examples of features
that may be visible in
SideVision™ images:
• Water: close to your vessel, the SideVision™
sonar beams may not interact with any solid
objects in the water column until they hit the sea
floor. The water column close to your vessel is
displayed as a dark band in the image. The abrupt
change to a lighter section in the image indicates
where the sea floor is first detected with each ping.
• Bait ball: objects in the water column close to your
vessel may be detected before the SideVision™
beams hit the sea floor. In this example, a bait ball
is shown within the water column, at a distance of
approximately 30 feet from the vessel.
• Vegetation: objects in contact with the sea floor
that are close to your vessel may be clearly visible
in the image at the point where the
SideVision™
beams hit the sea floor. In this example, the
shapes in the image indicate vegetation attached
to the sea floor.
• Structure: the lighter regions of the SideVision™
image represent the sea floor. It may be possible
to detect differences in the bottom material (for
example, where an area of mud meets an area
of gravel) as well as solid structures such as
pipelines and piers. Larger solid structures, and
sea floor relief, may reveal an area of shadow
directed away from your vessel.
Note: Unlike DownVision™ , SideVision™ does
not provide direct depth readings. The scale
shown across the top of the image indicates the
distance of features from your vessel.
266 a Series / c Series / e Series