Canon XL1 3CCD Camcorder User Manual


 
DEPTHOFFIELD
Manipulatingdepthoffieldcanlendcomplexitytoashotandcanoftenchangethemoodor
connotationoftheshot.Itisthereforeausefultooltousebutcanbedifficulttogetright.Whenyou
dogetitrighthowever,itlendsthepieceacertainedge.
BasicallyagreatDepthofField(DOF)meansagreaterareaoffocalpossibilities.
TherearethreewaystomanipulateDOF:
1.Iris
Thismanipulatestheamountoflightcominginandthereisadirectrelationshipbetweenhowmuch
lightisletinandthedepthoffieldachieved.
Essentiallythelowerthefstopnumberontheiriscontrol,themoreopentheirisandthehigherthef
stopnumber,thelessopentheirisis.
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alowernumberthenletsinmorelightwhileahighernumberletsinlesslight.
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IntermsofDOF:
Asyougohigher,youmaintainDOF.
‐Smallernumbersallowmorethingstobeinfocus
‐HighernumbersallowgreaterDOF,meaningthemainobjectisinfocusandtheothersaren’t.
Summary:
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WideIris=ShallowDOF
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SmallIris=GreaterDOF
Tip:
Becarefulofplayingwiththeirisindaylight;youcan’tpushuptheiristoomuchwhenthere’s
naturallightotherwiseyou’lljustgetburnout.
2.FocalLength(Zoom)
Thisreferstohowfaryouarezoomedinrelationtotheopticalcentreofthecamera.
Morezoommakesforincreasedfocallength.Lesszoommakesfordecreasedfocallength.
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IntermsofDOF:
‐LongFocalLength=ShallowDOF
(thisgenerallyallowsyoutogiveamorecreativeeffectvisuallyandcanbeusedtoobtaincertain
dramaticeffects)
‐ShortFocalLength=GreatDOF
(Hereeverythingisinthesamefocalplainsoeverything’sclear)