Canon XL1 3CCD Manual

A SERVICE OF

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DEPTHOFFIELD 

Manipulatingdepthoffieldcanlendcomplexitytoashotandcanoftenchangethemoodor

connotationoftheshot.Itisthereforeausefultooltousebutcanbedifficulttogetright.Whenyou

dogetitrighthowever,itlendsthepieceacertainedge.

BasicallyagreatDepthofField(DOF)meansagreaterareaoffocalpossibilities.

TherearethreewaystomanipulateDOF:

1.Iris

Thismanipulatestheamountoflightcominginandthereisadirectrelationshipbetweenhowmuch

lightisletinandthedepthoffieldachieved.

Essentiallythelowerthef‐stopnumberontheiriscontrol,themoreopentheirisandthehigherthef‐

stopnumber,thelessopentheirisis.

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alowernumberthenletsinmorelightwhileahighernumberletsinlesslight.

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IntermsofDOF:

Asyougohigher,youmaintainDOF.

‐Smallernumbersallowmorethingstobeinfocus

‐HighernumbersallowgreaterDOF,meaningthemainobjectisinfocusandtheothersaren’t.

Summary:

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WideIris=ShallowDOF

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SmallIris=GreaterDOF

Tip:

Becarefulofplayingwiththeirisindaylight;youcan’tpushuptheiristoomuchwhenthere’s

naturallightotherwiseyou’lljustgetburnout.

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2.FocalLength(Zoom)

Thisreferstohowfaryouarezoomedinrelationtotheopticalcentreofthecamera.

Morezoommakesforincreasedfocallength.Lesszoommakesfordecreasedfocallength.

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IntermsofDOF:

‐LongFocalLength=ShallowDOF

(thisgenerallyallowsyoutogiveamorecreativeeffectvisuallyandcanbeusedtoobtaincertain

dramaticeffects)

‐ShortFocalLength=GreatDOF

(Hereeverythingisinthesamefocalplainsoeverything’sclear)