Displayviews
Example7StartRangeinasurfacerelatedechogram
Inasurfaceechogram,settheStartRangevalueto0meters.Thiswillmakethe
echogramstartfromtheseasurface(providedthatthetransduceroffsethasbeen
dened).SetRangetothecurrentdepthplus20meters.Theechogramwillnow
showtheareafromtheseasurfaceanddownto20meters“below”thebottom.
Thebottomcontouriseasilydetectedwhenthedepthchanges.
ThebiomassisautomaticallycalculatedbasedonchoicesyoumakeintheCalculation
Intervaldialogbox;withinagiventimeframe,adenednumberofpings,oraportionof
theechogramview.Thedataisthentakenfromanechoareastartingimmediatelyafter
thetransmitpulse,andendingjustoverthedetecteddepth.
Ifyouhavelimitedyourverticalrange(usingtheRangeandStartRangesettings),the
resultingareaisusedforthebiomasscalculation.Iftheseabedisclearlydenedwith
auniquebottomdetection,thebottomechowillnot
beincludedinthecalculations.
Therefore,ifyouswitchthebottomdetectoroff,thebottomechowillbeincludedin
thecalculation.
Relatedtopics
•StartRangefunctiononpage146
•Rangefunctiononpage144
•Echogramdialogboxonpage206
Bottomechogram
Thisechogramisrelatedtothedetected
bottom.Stopdepth(lowerechogram
boundary)andverticalrangeare
manuallyselectedbytheStartDepth
andRangebuttonsontheMainmenu.
Theechogramisonlydrawnforpings
havingasuccessfulbottomdetection.
AThisisthestartdepthofthe
echogram.
Inabottomechogramitisnormally
itissetupwithStartRangesettoarelativesmallnegativevalue.Thevaluedenes
howmanymeterabovethebottomtheechogramwillstart.
BThisisthebottom.
Sincetheechogramisrelatedtothisbottom,itappearstobeat.Fishescloseto
thebottomistheneasytosee.
Therangefromthestartdepthabovethebottomanddowntosomedistancebelow
theactualbottomisdenedwiththeRangebuttonontheMainmenu.
CThistextidentiesthetransducerusedtocreatetheechogram.
351718/C
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