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Chapter 5. Perspective, Point of View, and Scale

Chapter 5. Perspective, Point of View, and Scale

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capturing.

Note

Thisbookisntanall-inclusivephotographybook,andthededicatedspacecannotreplacethe

numerousbooks,lectures,andclassesthataddresslensesandphotographicissues.Thissectionis

ratherjustarudimentaryguidetohowlensesworkandtheirspecificapplicationtocomposite

images.

FocalLength

Thefocallengthofalens,usuallyrepresentedinmillimeters,isacalculationofthedistancebetweenthe

pointatwhichlightraysconvergetoformasharpimageofanobjectthefocalpointoftherearnodal

pointwhenthelensisfocusedatinfinitytothefocalplane,whichindigitalcamerasisthesurfaceofthe

digitalsensor.A24mmlensisawide-anglelensbecauseithasacomparativelyshortfocallength,anda

400mmlensisatelephotooralonglens.Lensfocallengthdeterminestheangleofvieworhowmuchof

thescenewillbecaptured,andlensmagnificationdetermineshowlargeindividualelementswillbe.A

shortfocallengthhasawideangleofviewandtheobjectsinthescenearelessmagnified,whereasa

longfocallengthhasanarrowangleofviewandtheobjectsaremoremagnified.Focallengthalsoaffects

therelationshipofthebackgroundtotheforegroundandtheexpansionorcompressionofthescene.It

determinesthewayobjectsandpeoplearerenderedinthescene;thatis,iftheyaredistortedbytheir

proximitytoawide-anglelensorcompressedaswithatelephotolens.

Wideangletotelephoto



Wide-anglelensesrangefrom14mmto40mminthefull-frame,digitalcameraformatandare

recommendedwhenyouwanttoshowanexpansivescenethathasdepthandadistinctforeground,middle

ground,andbackground(FIGURE5.1).Theyareespeciallygoodforlandscapes,architecture,orcity

sceneswhereyouwanttodramatizetheperspective(FIGURE5.2andFIGURE5.3).Wideanglestend

toexpandthespatialrelationshipsofyourscene,whereastelephotoswillcompressandflattenthem.

Normallensesareusuallyintherangeof40mmto60mminthefull-frame,digitalcameraformat.



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Figure5.1.Thisdesertlandscapewasshotwitha28mmwide-anglelens.Noticehowthetransition

fromforegroundtobackgroundappearsvastandextended.



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Figure5.2.ThisphotooftheEiffelTowerwasshotwitha24mmwide-anglelens.Notonlydowide

anglesletyougetmuchclosertolargesubjects,buttheyalsoexaggeratethescalebythewaythey

distortthesubject.



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Figure5.3.ThisinteriorofNotreDamewasshotwitha14mmultrawide-anglelens.Itsavast

space,andthe14mmisabletocaptureagreatdealofitwithitswideangleofview.Asyou

decreasethefocallengthofyourlens,yougetmoredistortionofthesubject.



Note

Thetermfull-frame,digitalcameraformatreferstoanimage(orsensor)sizeof24mmì36mm,

whichwasthestandardsizefortheimageareaofphotographstakenon35mmfilmformanyyears.

Itsimportanttonotethatdependingonthesizeofyoursensor,yourlensfocallengthwillhaveadifferent

relationshiptoeachcorrespondingformat.Forexample,a50mmlensonafull-frame,digitalsensor

formatcameraisanormallens,meaningitseestheworldsimilarlytoyoureyeintermsofmagnification

andscale(FIGURE5.4andFIGURE5.5);itsnotwideortelescopic.ThesamelensonaDXor

croppedsensorcamerawouldbeconsideredashorttelephotobecauseitsessentiallyprojectingthesame

sizeimageonasmallerchip,whichgivesyoulessimageinformation.Inthissectiononlenses,well

refertoonlythefull-frame,digitalsensorformatforthesakeofsimplicity.



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Figure5.4.Thislandscapeimagewasshotwitha50mmlens,whichisconsideredanormallens.It

doesntmagnifyorreducethescaleoftheimagethatyouseewithyoureyes.



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Figure5.5.Thisgnarlyoldtreewasshotwitha70mmlens,whichisconsideredjustlongerthana

normallens;itslightlymagnifiesthescenefromwhatyoureyesees.

Thetelephotolensesrangefrom75mm1200mmandbeyond;eachhighernumbercorrespondstoa

narrowerfieldofviewandgreatermagnificationofyoursubjects.Thesearethemassivelensesyousee

prophotographersuseatbaseballandfootballevents.Telephotolensesaremoreusefulforisolatinga

singlesubjectfromadistanceandwillusuallythrowthebackgroundoutoffocusintheprocess

(FIGURE5.6).



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Figure5.6.Thisportraitoftwoyoungbaseballplayerswasshotwitha100mmlensatawide

aperture.Althougha100mmlensisnotconsideredalongtelephoto,noticehowtheout-of-focus

backgroundappearstoflattentheimageplane.

Forsuccessfulphotocomposites,itscrucialtohaveathoroughunderstandingoftheattributesofdifferent



lenses,becausewhenyoucombineimagesthatwereshotunderdifferentcircumstances,theresulting

imageshouldlookasthoughitwasshotwithasinglelensfromthesamepointofview.Ifnot,the

elementsinthecompositewilllookoutofplace,distorted,andoutofscale,andwillimmediately

transmitthemessageofapoorlydonecompositeimage.FIGURE5.7showsasinglescenethatisshot

withprogressivefocallengths.



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Figure5.7.Asinglesceneshotwitha24mm,50mm,100mm,and200mmlens,respectively.Notice

howthespatialrelationshipschangeasthefocallengthisincreased.

Aninterestingfactabouthowlensesrenderscenesisthatifyoucomparetheimagethatwasshotat

200mm(FIGURE5.8)withaversionoftheimagethatwasshotat24mmbuthasbeencroppedtoreveal

thesameimageinformation(FIGURE5.9),theimagesarevirtuallythesame.Changinglenseswillnot

changethewaythesceneisrenderedtothedigitalsensor;itjustchangesthemagnification.Thisisan

importantconcepttounderstandinthecontextofcompositing,becausedependingonthefocallength

youvechosenforthewholecomposite,youllneedtounderstandwhichlenstoshooteachelementwith

torenderthemnaturallyintothescene.Ifyouarecompositingelementsintoascenethatisshotwitha

normallens,youdontwanttoshootthemwithawideangleortheywontfit.



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Figure5.8.Theriversceneshotwitha200mmlensfromthepreviousexample.



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Figure5.9.Thiscroppedversionoftheriverscenewasshotwitha24mmlens.Theimagehasbeen

croppedtomatchtheimageareaofthe200mmscene.Noticehowalthoughtheresolutionismuch

lowerbecauseitssuchasmallsectionoftheframe,theelementsandspatialrelationshipslookthe

sameasthetelephotoshot.

Tip

Beforeyoushootasingleelementforanewcompositeimage,determinewhatangleofviewyou

wantthefinalimagetohave,andshootalltheelementswiththatattributeinmindfortheentire

process.

Backgroundrelationships



Asyouutilizedifferentfocallengthlenses,therelationshipoftheforegroundtothebackgroundchanges.

Withwide-anglelenses,thebackgroundappearssmallandinthedistance,andasyouincreasethefocal

length,thebackgroundmagnifiesprogressivelyinrelationtotheforeground.Ifyouphotographanelement

andmaintainitssizeintheframebutshootitwithlensesofvaryingfocallengthsfromwideangleto

telephotoyoucanseehowtheserelationshipschange.Thisisofparticularimportancewhenyouare

makingacompositeimageandyouwanttomaintaintheillusionthatyourimagewasshotthroughasingle

lens(FIGURE5.10).



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Figure5.10.Thefocallengthofthelensdeterminestheangleofviewandthedegreeof

magnification.Inthisexample,Katrinshotanobjectwithfourdifferentfocallengthlenses:18mm,

35mm,70mm,and300mm,eachtimekeepingtheobjectthesamesizeintheframe.Noticehowthe

backgroundrelationshipchangeswitheachlens.

Depthoffield



Depthoffieldreferstotherangeofdistancethatappearsacceptablysharpinyourimage.Theareaof

sharpnessinanimagedoesnotabruptlychangefromsharptounsharpbutinsteadtransitionsgradually.

Depthoffieldcanvarybasedonyouraperturesetting,thecameraformatyouareusing,yourproximityto

yoursubject,andtheexactpointinthesceneatwhichyoufocusthelens.Smallaperturesincreasedepth

offield,andlargeaperturesdecreasedepthoffield.Smallapertureshavevaluesthatarehighnumbers,

like11,16,and22,whereaslargeaperturesthatletmorelightintothelenshavevaluesthatarelow

numbers,like1.4,2.8,4,and5.6.

Atfirstglance,wide-anglelensesappeartohaveamuchgreaterdepthoffieldthantelephotosbecause

theyencompassawiderangleofviewandholdsharpnessthroughout(FIGURE5.11).Telephotolenses

appeartohaveashallowerdepthoffieldbecausetheyareoftenusedtomagnifythesubject(FIGURE

5.12).Ifyoushotthesamescenefromthesamepointatthesameaperturewithatelephotolensanda

wide-anglelensbutcroppedthesectionofthewide-angleimagetomatchthetelephotoimage,thedepth

offieldofthetwowouldbeidentical.YoucanreferbacktoFigures5.8and5.9,whichillustratethis,

althoughthecroppedsectionofthewide-angleimageappearstobesofterduetoitslowerimage

resolution.Whenyoureworkingwithcompositeimages,youmustpayparticularattentionnotonlytothe

depthoffieldoftheentirecomposition,butalsothedepthoffieldofeachelement.Forinstance,ifyou

chooseawide-angleviewwithavastdepthoffield(everythinginfocus)foryourfinalcomposite,and

thenyoushootseveralelementstocomposeintothescene,youmustmakesurethatthedepthoffieldfor

eachelementisadequatesothesubjectissharpfromfrontedgetobackedge.Ifoneofyourelementshas

ashallowdepthoffieldandalltheedgesarenotsharp(FIGURE5.13),itwillnotcomposeproperly

intoascenethatiscompletelysharp.Yourcompositionshouldbemadeentirelyofelementsthatare

completelysharp.Ifyouwanttocreatedepthoffield,youcandothisasalaststageofthecompositing

processoncealltheelementsareassembledinplace.



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Figure5.11.Photographstakenwithwide-anglelensesseemtohaveunlimiteddepthoffield,which

meansthattheentireimageissharpfromforegroundtobackground.ThisUtahlandscapewasshot

witha28mmlensatf/16.Usingasmalleraperturealsoincreasesdepthoffield.



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Figure5.12.Whenyoureshootingmacrophotography,evenashorttelephotolens,likethe70mm

lensusedhere,willgiveyouaveryshallowdepthoffield.Inotherwords,thefocuswillrapidlyfall

off,especiallywhenshotatawideaperture.Thispicturewasshotatf/5.



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Figure5.13.Thisflowerwasshotwithashallowdepthoffield.Itwouldnotbeagoodcandidatefor

acompositebecausesomeoftheedgesaresoft.Notonlywillitbehardtomaskwhencomposed

intoasharpscene,butitwilllookimmediatelyoutofplace.

ShutterSpeedandBlur



Fastshutterspeedsfreezemotionandslowshutterspeedsblurmotion(FIGURE5.14).Slow

shutterspeedsalsocreateinterestingeffectsifthesubjectismoving.InFIGURE5.15thestillshot

wasafour-secondexposurewhentheFerriswheelwasstopped,andthesecondimagewasafoursecondexposurewhentheFerriswheelwasmoving.Therearenumerousplug-insandtechniques

toaddmotionblurtoanimage,butopticalmotionblurisalwaysmoreauthenticlookingthan

motionblurthatissyntheticallyinducedviasoftware.Ifyouplanonaddingmotionblurtoasharp

imageinyourfinalcomposite,trytotakeafewframeswiththesubjectblurredtouseasanimage

assetorreference(FIGURE5.16).IfyouuseShutterPrioritymode,yousettheshutterspeedand

thecameraselectstheaperture.Thisisagoodmodetousewhenyouneedtoeitherfreezeorblur

motion.Thehighershutterspeeds,suchas1/1000sec.or1/500sec.,willfreezemotionverywell;

onceyougetdownto1/60sec.youllstarttoseetheblurringeffectofmovingsubjects,andeven

moresoasyougoslowerwiththeshutter.



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Figure5.14.Thecrispwaterwasexposedwithaveryfastshutterspeedof1/30ofasecond.The

velvetywaterwasexposedwithaslowshutterspeedofthreeseconds.



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Figure5.15.Usingatripodduringlongexposuresletsyouexperimentwithcombiningcrispimage

elementsandmotioninthesameframe.



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Figure5.16.ViewingimagesonadigitalcamerabackLCDscreenletsyoulearnwhile

photographingandexperimentingwithshutterspeedanddepthoffieldeffects.



PointofView

Asphotographers,wearealwayssearchingforauniqueangleorviewoftheworldthatwillresultina

greatpicture.Morethantheaverageperson,wereconstantlylookingforadifferentviewofoursubjects.

Werecuriousaboutwhatthestreetmightlooklikefromaparticularwindow,fromthefireescape,or

fromgroundlevel,orperhapsevenfromunderwater.Mostoften,weprobablyendupshootingfromeye

levelbutwonthesitatetocrouchdownorstandonaparkbenchtogetabetterangleforourshot.Thisis

simplyknownasourpointofview.

Incompositework,oncewechooseourpointofview,allthephotographicelementsthatmakeupthe

finalcompositeimagemustbeshotfromthesamepointofview,oratleastappeartohavebeenshotfrom

thesamepointofview.Theymustalsobeincorrectperspectivetothechosenpointofview.Well

discussextensivelyhowtomatchperspectiveamongyourelementsalittlelaterinthechapter.Itisfairly

criticaltoestablishyourpointofviewearlyinthephotographyprocesssoyouhaveaspecificblueprint

forhowyoullshootallyourelements.Ifyoustartwithaneyelevelpointofviewinmindandbeginto

shootyourbackgroundandelementsandthendecidehalfwaythroughtheprocessthatyoudratherusea

highervantagepointofview,youllhavetoreshootallthoseelementsagainatthenewangle.Yourpointof-viewchoiceshouldbepartoftheplanningprocesswediscussedinChapter3,Planningand

Preparing,orattheveryleastshouldbethefirstphotographicdecisionyoumake.

Eye-levelViewpoint

Dependingonhowtallyouare,youprobablyshootmostofyourpicturesfrombetween5and6.5feet

fromtheground,yourstandingeye-levelviewpoint.Thisisyourvantagepointmuchofthetime,and

especiallyifyoutakealotofphotographs,thispointofviewwillbeacommonthreadamongthem.

Althoughitsthemostobviousviewpointtophotographfrom,itsacompletelyvalidchoiceformany

photographiccircumstancespreciselybecauseitdoesntbringattentiontoitselfasauniquepointofview.

Thepointofviewbasicallybecomesinvisiblebecauseviewersaresousedtoseeingimagesandthe

worldfromthatviewpoint.Asaresult,theviewerbecomescompletelyabsorbedinwhatishappeningin

theimage(FIGURE5.17andFIGURE5.18).



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Figure5.17.AParisianstreetsceneshotfromeyelevel.Inphotographslikethisthepointofview

doesnotdrawattentiontoitselfbutinsteadbecomesinvisible.



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Chapter 5. Perspective, Point of View, and Scale

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