Simrad’s
ForwardScan
will warn of
underwater
obstructions
off the bow.SIDEWAYS GLANCE
T
he trouble with down-looking sys-
tems is that they can only see what’s
under your boat. Side imaging, on
the other hand, can shoot out to both port
and starboard.
Side imaging appeared before down-
scanning systems. About 13 years ago,
Humminbird introduced the fi rst af ord-
able side-imaging system. Since then, the
technology has advanced, and the number
of companies that of er this capability has
increased to include Garmin (SideVu),
Lowrance/Simrad (StructureScan HD
Side Scan) and Raymarine (SideVision).
Like down imaging, side-imaging sys-
tems scan in thin slices. The transducer
uses two electronic beams, each shooting
sideways and slightly downward. The sys-
tem puts together pictures of each side on
the display as the screen scrolls from the
top downward. As with down-scanning sys-
tems, images emerge with lifelike, almost
eerie clarity, albeit in monochrome shades
(again, think ultrasound medical imaging).
Side-imaging systems can reach out to
remarkable distances. Garmin’s SideVu, for
example, is ef ective to around 500 feet on
each side of the boat. Raymarine’s CHIRP
SideVision can reach to distances of 600
feet on each side.
One of coolest features of such systems
lies in the ability to create an instant way-
point on your chart plotter for an object or
school of fi sh that is a considerable distance
from your boat.
With the Lowrance HDS Carbon MFDs,
for example, just tap the school, rock pile or
other object of interest on the touchscreen,
and the system will create a waypoint with
the precise latitude and longitude of that
spot. You can do this even after the boat is
well past the spot. With the waypoint re-
corded, you can back-zig over and take a
closer look with your fi sh fi nder or down-
imaging system.
As with down imaging, side-imaging
technology works most ef ectively at boat
speeds of under 5 mph. Also, most systems
cannot see directly under the boat, and that
leaves a blind spot between the side im-
ages. However, MFDs allow you to split the
screen so you can use both side imaging and
the conical fi sh fi nder and/or down imaging
simultaneously. You won’t a miss a thing.FULL FRONTAL
S
ome systems can also
look forward to help
you avoid shoals or
spot fi sh of the bow of the
boat. This includes Garmin’s
Panoptix Forward technology.
With Garmin’s PS31 transom-mount
transducer and a compatible Garmin
MFD, you can see as far as 300 feet ahead
of the boat. A beam sweeps at 417 kHz
while aimed forward and slightly down-
ward. You can also use the PS31 with a
special bow-mounted trolling-motor
bracket to scan in any direction you want
while fi shing.
Choose Panoptix LiveVu Forward
mode for color images of the bottom and
fi sh. It is continually refreshed in a two-
dimensional format. You can actually
track fi sh and lures as they move through
the water. The RealVu 3D mode creates
a three-dimensional view of the bottom,
structure and fi sh that updates every one
to four seconds. In other words, the im-
age does not scroll, but rather the whole
screen refreshes.
Garmin and Simrad also have systems
designed primarily to keep skippers ap-
prised of changes in depth and obstructionsPHOTOS: (FROM TOP) COURTESY LOWRANCE, COURTESY GARMIN
AS WITH DOWN-
SCANNING SYSTEMS,
IMAGES EMERGE WITH
LIFELIKE, ALMOST
EERIE CLARITY, ALBEIT
IN MONOCHROME
SHADES (THINK ULTRA-
SOUND IMAGES.
With Garmin’s SideVu system, objects take shape in images that are easy to interpret.BOATINGMAG.COM | APRIL 2018 | 87