with a continuously updated 2D display of
what’s ahead. Garmin’s Panoptix Front-
Vu uses the PS51TH through-hull 417
kHz transducer, while Simrad’s uses the
ForwardScan through-hull 180 kHz trans-
ducer for its forward-looking sonar. Both
the Garmin and Simrad will reach out to
8x the current bottom depth.THREE-DIMENSIONAL
W
hile Garmin has RealVu 3D,
Furuno, Lowrance, Raymarine
and Simrad also of er three-
dimensional representa-
tions of the underwater
world and its inhabitants.
Lowrance and Simrad
do this with an add-on
module called Structure-
Scan 3D. Raymarine of ers
this with RealVision 3D in
its Axiom and Axiom Pro
MFDs. Such 3D modes
are actually software-
enhanced displays of the
combined down- and side-
imaging sonar returns.
The same software
enhancements let you manipulate the 3D
representation with the touchscreen to
view the image from virtually any perspec-
tive that you choose. Both RealVision 3D
and StructureScan 3D let you zoom, pan,
tilt and rotate the image. You can even look
at it from underneath.
Three-dimensional modes also add
color elements to the imaging sonar dis-
plays. Fish suspended in the water column
appear in a dif erent color from the other-
wise monochrome imaging of the bottom
contours, allowing you to more easily dis-
tinguish such targets.
Garmin’s transom-mount Panoptix
PS30 transducer can deliver the RealVu
3D Down and RealVu 3D Historical modes
when matched with a compatible Garmin
MFD. RealVu 3D Down allows you to view
the history of one transducer sweep while
your boat is stationary, while RealVu 3D
Historical creates a three-dimensional view
of what has passed under the hull. This sys-
tem also of ers LiveVu Down for real-time
imaging and the ability to see fi sh moving
toward or away from your boat.
Furuno’s DFF3D scanning sonar systemincludes a variety of display modes, one
of which is a three-dimensional view of
the underwater world. DFF3D uses an
add-on module networked with Furuno’s
NavNet TZtouch and TZtouch2 MFDs.
A special multibeam transducer scans
120 degrees in a continuous swath (with
no blind spot under the boat), and in the
3D History mode paints a color three-
dimensional image. Fish are shown in a
distinctive shade, and you can also set the
color palette to depict the depths of bottom
contours. The DFF3D reads out to 650 feeton both sides of the boat and up to 980 feet
straight down.
The DFF3D system can also image in
real time. The cross-section display mode
continually updates as the sonar beam
sweeps from side to side.FULL CIRCLE
T
here’s a number of ways to im-
age the underwater world in a
full circle around the boat. One
of the most af ordable is Humminbird’s
360 Imaging system. It uses a retractable
transducer that electronically scans 360
degrees and will reach out to scan up to
150 feet from the boat.
When matched with a compatible
Humminbird MFD, the system updates
the screen with every rotation of the trans-
ducer beam. Returns are depicted in a two-
dimensional yet lifelike, monochromaticSTABILIZED
TRANSDUCERS
Miniature stabilizing systems for
transducers represent the latest
technology trend in fish-finder and
imaging systems. You’ll find such
stabilizing features in the transduc-
ers for Furuno’s DFF3D multibeam
network sonar and Raymarine’s
RealVision 3D system in the Axiom
and Axiom Pro MFDs.
These systems are similar to the
miniature multiaxis motion sensors
in mobile phones. In transducers,
they mitigate the effect of sea con-
ditions on bottom readings. This
smooths the typical saw-toothed
pattern you see on bottom readings
when a boat is heaving.
In addition, the technology
compensates for pitch and roll,
which can adversely affect the
beam angle of the transducer. The
attitude and heading reference
sensor (AHRS) in transducers for
Raymarine’s RealVision 3D system
also compensates for yaw to help
eliminate distortion of DownVision
and SideVision imaging as the boat
is turning.
PHOTOS: (CLOCKWISE FROM TOP LEFT) COURTESY RAYMARINE (3), COURTESY GARMIN, COURTESY SIMRADRight top:
Lowrance’s
StructureScan
3D displays
images
in three
dimensions.
Right bottom:
Furuno’s
DFF3D
sweeps side to
side in a con-
tinuous swath
to create high-
resolution 3D
images.88 | BOATINGMAG.COM | APRIL 2018