StarTrailPhotography

• Astartrailisatypeofphotographthatuseslongexposuretimes,ormultipleexposures,tocapturetheapparentmotionofstarsinthenightskyduetoEarth'srotation.Astar-trailphotographshowsindividualstarsasstreaksacrosstheimage,withlongerexposuresormoremultipleexposures,yieldinglongerarcs.

WhyareStarTrailsCircular?• Startrailsoccurbecausestars"move"acrosstheskyastheEarthrotates,andsowhenacamerakeepsits’shutteropenforanextendedperiodoftime,itwillabsorbthismovinglightaslighttrails.ThecircularpatternoccursduetothefactthattheEarthisrotating.

WhereShouldIGo?• Lookforlocationsthatarehavesomeforegroundinterest.Itmaybeanabandonedbuilding,largeinfrastructurelikearadiotowerorabridge,orsomenaturalfeatureslikerockformationsorbigtrees.

WhereShouldIGo?• Youmaychoosetoaddlighttothesefeatures,withaflashlight,orkeepthemassilhouettesagainstthestar-filledsky.

WhereShouldIGo?• Thoughitispossibletocapturestartrailsintown,itismucheasierifyoutrythisfarawayfromanycitylights.Citylightsthatarenotevenvisibletothenakedeyewillshowupoveralongexposure.

• LightpollutionfromtheMoonshouldalsobeavoided.

WhereShouldIGo?• Itreallypaysoffdoingsomeresearchbeforeembarkingonashoot,especiallyifyouhaveneverbeentothelocationbefore.

• Ifyouwanttogetthe“spiral”effect,youmustestablishwheretheCelestialSouthPoleislocated.

• TherearemanyfreeAPPSthatwilltellyouwheretopointyourcameratofindtheCelestialSouthPole.

• Iusethefollowingmethod…

WhereShouldIGo?

Focusing• Inthedark,itisnoteasytogettheAFtolockontoanything,butdonotworry….thereareseveralsolutionstothis.

Focusing• Ifyouareincludingforegroundobjects,Isuggestmakingsurethattheyareinfocus.Ifyouareusingawideanglelens,theforegroundobjectandthestarswillprobablybothbeinfocusevenataverywideaperture.Ifindthatitisfairlysafetojustsetthefocustoinfinityifitisawideangleorfisheyelensrightfromthestart.

Focusing• Onceyouhaveachievedthestateof“infocus”,besuretosetittoMFormanualfocusbeforestartingyourexposureoritwillstartsearchingagainwhenyoustarttheexposureandyouwillloseyourfocus.

Composition• Whencomposingtheshottrynottoincludeanydirectlightsources,likestreetlights,intheshot.

WhiteBalance• Whitebalancecouldbeawholeseparatetutorialonitsown.IalwaysshootinRawwiththeWhiteBalancesettoCloudy.AdjustmentstotheWhiteBalancecanbemadelater.

SingleShotvsStacking• Forshootingoptions,onecouldchoosetodoitallinoneshotorshootmultipleshotsand“stack”themlaterusingcomputersoftware.Ipersonallyfindthatshootingmultipleimagesandstackingthemyieldsmuchnicerimagesthanthosedoneallinoneshot.

SingleShotvsStacking• Ifyouaregoingtodoitallinoneshotthenyourbiggestconcernshouldbenoise.Idonotusethesingleshotbutusethestackingmethodforthisreason.

Stacking• AsIsaidbefore,mypreferredwayofshootingisshootingmultipleshotsand“stacking”themlaterusingcomputersoftware.Shootingshortexposurepicturesmeanslessnoise,soonecanshootwithawideapertureandafasterISOthatwillpickupmanymorestarsthantheoneshotmethod.

StackingSettings• ThesettingsIgenerallyuseare:• ISO200• ApertureF2.8• Shutter25sec• Intervalofsay30secbetweenexposures• Focusinfinity

StackingSoftware• StarStaX.• ThisistheSoftwareIuse.Unlikeotherfreeprograms,itrunsonMacaswellasWindows.WhatIlikeaboutStarStaXistheincrediblespeed.ItismuchfasterthanusingPhotoshop.

• IuseLightroomandStarStaXwhichIwilldemonstratelater.

StackingSoftware• Photoshop.• Thismethodgetsthejobdonebutisslowandtiesupmemorywhilestacking.

• ThereareYoutubevideosshowingtheuseofAdobeBridgeandPhotoshoptostackstarphotos.

StackingSoftware• Startrail.exe• GoodprogrambutonlyavailableforWindows.

EquipmentNeeded• Camera• Tripod• Intervalometer• Torch• Somemeansofheatingthelenstopreventdewforming

• IuseaDIYlensheaterrunningoffa12Voltbatterypackwhichkeepsthecamera/lensatabout25degC.

LensHeater