InterpretingSideVisionâ˘images
ThefollowingillustrationshowshowSideVisionâ˘imagesonyourmultifunctiondisplayarerelatedtothe
watercolumnandseaîoortothesidesofyourvessel.
InterpretingSideVisionimages
SideVisionâ˘imagesareconstructedline-by-line,
similartothewayatelevisionpictureiscomposed
ofmanyhorizontallines.Eachsuccessiveping
fromtheSideVisionâ˘transduceraddsanewline
ofimagedatatothetopofyourdisplay.Eachnew
lineshowssonarreturnsfromboththeportand
starboardsidesofyourvessel.
Asnewlinesareaddedwitheachsuccessive
ping,olderdatagraduallyscrollsdownthedisplay,
buildingupadetailedimageofthewatercolumnand
seaîoortothesidesofyourvessel.Ifyourvessel
maintainsthesamebearingandspeedforaperiod
oftime,youcaninterprettheimageasaplanofthe
seaîooralongyourvesselâscourse.
Theillustrationalsoidentiîżesexamplesoffeatures
thatmaybevisibleinSideVisionâ˘images:
â˘Water:closetoyourvessel,theSideVisionâ˘
sonarbeamsmaynotinteractwithanysolid
objectsinthewatercolumnuntiltheyhitthesea
îoor.Thewatercolumnclosetoyourvesselis
displayedasadarkbandintheimage.Theabrupt
changetoalightersectionintheimageindicates
wheretheseaîoorisîżrstdetectedwitheachping.
â˘Baitball:objectsinthewatercolumnclosetoyour
vesselmaybedetectedbeforetheSideVisionâ˘
beamshittheseaîoor.Inthisexample,abaitball
isshownwithinthewatercolumn,atadistanceof
approximately30feetfromthevessel.
â˘Vegetation:objectsincontactwiththeseaîoor
thatareclosetoyourvesselmaybeclearlyvisible
intheimageatthepointwheretheSideVisionâ˘
beamshittheseaîoor.Inthisexample,the
shapesintheimageindicatevegetationattached
totheseaîoor.
â˘Structure:thelighterregionsoftheSideVisionâ˘
imagerepresenttheseaîoor.Itmaybepossible
todetectdifferencesinthebottommaterial(for
example,whereanareaofmudmeetsanarea
ofgravel)aswellassolidstructuressuchas
pipelinesandpiers.Largersolidstructures,and
seaîoorrelief,mayrevealanareaofshadow
directedawayfromyourvessel.
Note:UnlikeDownVisionâ˘,SideVisionâ˘does
notprovidedirectdepthreadings.Thescale
shownacrossthetopoftheimageindicatesthe
distanceoffeaturesfromyourvessel.
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