Target Indications - Raymarine DS400X Owner's Handbook Manual

18 DS400X and DS500X Digital Fishfinders

Target Indications

When the sounder detects a target echo such as a fish, it displays a
representative image on the LCD. The shape and size of this image is
influenced by a combination of factors:
Boat speed
The shape of the target changes along with your speed. Slower speeds return
flatter, more horizontal images. As your boat's speed increases, the image
will tend to thicken and arch slightly.
The depth of the target
The closer the target to the surface the larger the image on screen.
To display the depth of individual targets, switch on the TARGET DEPTH ID
from the menu, as described on page 44.
The size of the target
The larger the target, the larger the return on the fishfinder display. The size of
a fish target is however dependent upon the size of the fish's swim bladder
rather than its overall size. This swim bladder will vary in size between
different breeds of fish.
The frequency of the transducer
The same target will appear differently when the transducer frequency is
changed. Generally, the lower the frequency the broader the image.