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1、如有你有帮助，请购买下载，谢谢!HyperfocalFocusingWhenshouldyouusehyperfocalfocusing?Well,sometimeswhenshootingalandscape,youwanteverythingsharpfromthefronttothebackofthescene.Settingasmallaperturesuchasf/16,f/22orevenf/32canhelp,butifyoureallywanttomaximzedepthoffieldhyperfocalfocusingisthe
2、techniqueyouneedtouse.Todothis,youneedacamerawhereyoucanswitchtomanualfocusingandalensinscribedwithadepthoffieldscale(notallmodernlenseshavethesemarkingsthesedays,especiallyzoomlenses).Ifyou'renotfamiliarwiththesekindsoflensmarkings,here'saquickexplanation:LensMarkingsPrimerT
3、hepicturebelowofatypicallens(inthiscasea28mm)showsfoursetsofmarkings.Attopisthedistancescale(onthelens'focusbarrel)showingfiguresinfeetandmeters(thisalsoshowstheinfinityposition).Belowthatareasetoflinesbeneathwhicharethef-stopsofthelens.Thisisthedepthoffieldscale.Foreachf-sto
4、p,therearetwoequidistantmarks,onetotheleftandonetotherightofthecentralmarkonthescale.Thebottomsetoffiguresshowstheselectedf-stopforthelens.Theseareonthelensapertureringand,asyouchangetheaperture,theselectedf-stopunderthecentrallineonthedepthoffieldscalewilltellyouwhataperture
5、you'veselected.Tofindoutwhatpartofasceneisinfocusissimplyamatterofreadingthedistancescalesbetweenthetwomarksforyourselectedf-stoponthedepthoffieldscale.Forexample,let'ssayI'vefocusedonsomethingthat's3feetaway.Ifmylensissetatf/2.8,thenreadingthedistancevaluesatthetwo"2.8"marks
6、onthelensshowsthateverythingjustshyof3feettoabout3.5feetwillbeinfocus(alittleguesstimationisrequiredinreadingthedistances).Thisisfineforisolatingyoursubjectfromeverythingelse.IfIclosethelensdowntof/11,thenreadingthedistancesforthetwo"11"marksshowsthateverythingbetweenjustover
7、2feetand5feetwillbeinfocus.Ifthelensissettofocusoninfinity(theinfinitymarkisoverthecentralmarkonthedepthoffieldscale),thenyouonlyneedtoreadoffthedistancevalueforthef-stopmarktotheleftofthecentraldepthoffieldscaleaseverythingbetweenitandinfinitywillbeinfocus.Inthisnextpicture,
8、ifI'dsetmyf-stoptof/5.6,everythingfromjustover10feettoinfinitywouldb
