Humminbird 1197C SI - Manual (Page 63)

Side Imaging: On the Water Interpretation
(1197c SI Combo models only)
Use the following side imaging examples to help you interpret the side imaging display.
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: A Closer Perspective and the Submerged Bridge
graphics on the next page for examples of this.
New Bridge Pilings 1
Creek Channel 2
Submerged Bridge, Creek Channel and New Bridge Pilings
Submerged Bridge 3
3
2
1
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