Canon XL1 3CCD Manual

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Capturingvideo

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‐Thetypeofvideo,orformat,andtoalesserextenttheconnectiontypeyouselecttocapturecontent,

candramaticallyaffectthequalityofthevideoonthecomputer.‐It’salwaysdesirabletostartwith

thehighestpossiblequalityvideoandaudiosignal.

‐Thehigherthequalityofthesourcematerialused,thehigherthequalityofthefinalcompression

results.

Today’seditingsoftware,suchasAdobePremiere®Pro,andmanycompressionsoftwaretools,can

capturecontentinavarietyofways.Videocanbecapturedfromanalogueordigitalsources.Both

haveavarietyofdifferentvideoandaudioformatsavailableandvariousphysicalconnectiontypes

thatcanbeused.

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SIGNALFORMATSANDCABLES

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•Analogueformats:

‐Analogvideousesfluctuatingvoltageandfrequencysignalstotransmitimage

data.

‐Rangesgreatlyinqualitybutisinherentlysusceptibletovisualinterferencefromelectronicnoiseand

suffersattenuation,orthelossofsignalpowerandqualityoverlongcableruns(usually300metersor

more).

‐Equipmentthatsupportsanalogsignalsisgenerallymoreaffordable

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Becausecomputersonlyusedigitaldata,theanalogsourcemustbeconvertedtoadigitalcopytobe

captured.Whenitissentbacktoananalogmediumlikevideotape,itisconvertedbacktoananalog

signal.Thisconversioncanleadtominorerrors(quantizationerrors)beingintroduced.

Youcanminimizethesequantizationerrorsbyusingtherightformat,goodequipment,cables,and

connections.

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•Composite:

‐Acompositevideosignalcarriestheluminanceandthechrominancechannelsinasinglesignal.

‐Biggestproblem=thatlumainformationcanleakintochroma,andviceversa.Thisleakagecanlead

tonoise,knownaschromacrawl,whichcanbeamplifiedbythevideocaptureprocessandreducethe

overallquality.