Amateur Photographer - UK (2020-03-28)

18

Technique

19

Depth-of-fieldpreviewbutton

Depth-of-fieldbuttonsareusefultoolswhenworkingwithaperture.For

DSLRuserstheeasiestwaytoexperimentwiththisfeatureis toputyourcamera

intotheapertureprioritymodeandstartingat thewidestaperturesetting,hold

downtheDOFpreviewbuttonandstopyouraperturesettingdown.Your

viewfinderwillbecomedarker,howeverthatis becauseyouraperturesettingis

closingthereforelettingin lesslight.Onceyoureyesadapttothedarkerviewyou

canviewwhatis in andoutof focusthroughtheviewfinder.

Withmirrorlesscamerasit is a differentsystem.Theyshowa trulyaccurate

depth-of-fieldpreview,withouttheviewfinderdarkeningat smallapertures.They

alsogivea muchmoreaccuraterepresentationof thedepthof fieldand

backgroundblurwithfast lenses than DSLRs do, which is owing to the design of

the focusing screen.

17

Funfact
Didyouknowthe
widesteverapertureon
a lenswenttof/0.7!The
Zeiss50mmf/0.7was
builtbyNASAforthe
Apollolunarprogramto
capturethefarsideof
themoonin 1966.In
totaltherewereonlyten
lensesmade.Onewas
keptbyCarlZeiss,six
weresoldtoNASA,and
threeweresoldto
StanleyKubrickforhis
movieBarry Lyndon.

15

Brilliantbokeh
Bokehis a Japanesewordandrefestothe
visualqualityof theout-of-focusareasof animage.
Photographersusebokehtocreatedreamy,blurred
images.Toachievebrilliantbokeh,youneeda lensthat
canopenwideup– primelensesaregenerallybestfor
bokehastheycanopenwide.F/2orloweris
recommended.Keepasmuchdistanceaspossible
betweenyoursubjectandbackgroundtomakethe
blurredareasmoreblurred.Goodbokehis considered
tohaveroundhighlightsratherthanpentagonshapes
andtheedgesof thehighlightsshouldbesoftnot
haloed or hard-edged. Lenses will vary between quality.

20

Telephotoforblurred

Thelongeryourlensandthewideryour

aperture,themoreyouwillblurthebackgroundand

isolateyoursubject.Wildlifeandportraitureareboth

beneficialforthisstyleof shooting.Aswellasyour

aperturesettingit makesa differencehowcloseyou

aretoyoursubject,andhowclosetheyaretothe

background.Justremembergenerallythelongerthe

lens, the wider the aperture, the creamier the effect!

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Wideforsharpness

Wideanglelensesobtainanapparent

greaterdepthof fieldcomparedtoa telephoto

lensbecausetheycovera widerview.Forexample

ona full-framecamera’ssensorif yousetyour

aperturetof/4ona 35mmlenswiththesubject

youarefocusingonat 10m,thenyourdepthof

fieldis goingtobe414.46m.If youswitchtoa

50mmlenswithalltheothersettingsexactlythe

sameyourdepthof fieldwillbecome12.37m.

Wideanglelensesaregreatforphotographing

sceneswhereyouhavesubject/sat different

distance/sfromthebackground but want them

both to appear in focus.

16

Field
curvature
Fieldcurvaturecausesa
flat objecttoappear
sharpin onlypartsof the
frame.Thebestwayto
correctthisproblemis to
stopdownyouraperture
onyourlens(if youstop
downtoofaryourunthe
riskof diffractionso
weighuptheodds).
Generallytelephotofocal
lengths(100mm
upwards)aremuchless
likelytoshowfield
curvaturethannormal
andwideanglefocal
lengthlenses.If youcan’t
fix theproblemstopping
downtheaperturethen
you’llneedtoconsider
focus stacking.

Awideanglelensis

bestforkeeping

everythingin the

scene sharp

Zoomin for

portraitsto

isolatethe

subjectand

blurthe

background

Fairylightsaregreatfor

thebokeheffectand

yourapertureneedsto

be opened wide

Thedepth-of-field

previewbuttonhelps

toensureeveryoneis

sharpin a group

portrait