varietyofsystemsenablingthecameratoreadtheamount
oflightenteringitandinformingthephotographerofthe
correct exposure level. Each will take light readings in
differentwaysandfromvaryingproportionsoftheframe
to create a reading. Understandinghow these workand
howtheyreadthelightcanaffectthefinaloutcomeofthe
image.
Average Metering
Inaveragemetering,asthenamesuggests,thecamerawill
make an average readingfrom the whole sceneand the
lightenteringthecamerafromthis.Howeverproblemswill
occurwiththiskindofmeteringwhentheframehasany
extremesoflightordarkareasthatcouldaffecttheoverall
reading.Forexamplethereadingfromaportraittakenina
very bright or dark scene would not be particularly
accurate,andthefaceoftheportraitwouldbecomeeither
over-orunderexposedasthecameratookthereadingfrom
alloftheinformationcontainedwithinthescene.Clearly
for a satisfactorily exposed face this would not be
beneficial for the portrait.
Spot Metering
Thespotmeterwilltakealightreadingfromanareaofthe
frameanywherefrom 1 to 5 percentoftheoverallimage,
usuallyfrom thecentral pointofthe lens althoughwith
some cameras this pointcan be changed.It is themost
accurateandsensitiveofallthereadingsavailabletothe
photographer.Thepointfromwhichthereadingistakenis
preciseandwillnotbeinfluencedbyanyotherareaofthe
image in any way. In a portraiture scenario the