For Best Performance - Humminbird HELIX 5 SI GPS Operation Manual

For Best Performance

Use the following tips and examples to help you interpret the Side Imaging display.
Side Imaging Tips
Boat speed: Side Imaging is best performed at boat speeds between 2 to 6 mph. If the boat is
stationary, the same information is displayed over and over. If the boat is moving very quickly,
there will be gaps between the strips of information. The best boat speed to use will depend on
the side range selected. Slower speeds are good for longer ranges, while faster speeds can be
used at shorter ranges.
Boat navigation: It is important to understand that when the boat turns, successive beam strips
to one side will begin to overlap and the strips on the other side will fan out, providing some
distortion to the image. Because of this, the best imaging performance is produced by straight
line navigation and minimal side-to-side boat motion (i.e. wave induced, etc.). This applies to
navigation by either the main engine or the trolling motor. Minimize turning time and avoid wave
action that induces large side-to-side rocking of the boat. For example, if there is a lot of wave
activity, try to move the boat so that it is perpendicular to the waves instead of parallel with the
waves in order to minimize the side-to-side rocking of the boat.
Beam Coverage: When there is an area directly under the boat that does not have SI beam
coverage, this area will be covered by the standard 200/83 kHz down-looking beam and displayed
in the Sonar views. The net effect of this, on the display, is that a single object may appear as two
separate entities, when in reality, it is one continuous object. See Submerged Bridge: Creek
Channel and New Bridge Pilings and the Submerged Bridge: Alternative Perspective illustrations
for examples of this.
See humminbird.com for a side imaging sonar tutorial and additional information.
What's on the Side Imaging Display
Boat speed: 2 to 6 mph
Straight line navigation
Minimum turning time and wave turbulence
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