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Chapter 1. Digital Photography from 50,000 Feet

Chapter 1. Digital Photography from 50,000 Feet

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RebelhasalreadybeenreplacedbyanimprovedDigitalRebelXT.Newdigital

SLRsfromNikon,Minolta,Pentax,andOlympusareclusteredaroundthe$1000

pricepointandfarbelow.Evenmoreimportantforphotoenthusiastsarethenew

non-SLRmodelsatevencheaperpricesthatarestillbedeckedwith7-to8megapixel(andhigher)sensors,longerzooms,andsophisticatedfeatures.

Seriousphotographerstodaycangetinonthegroundfloorfor$500orless.

So,traditionalistfilmphotographershavetransformedthemselves,oneafter

another,intocomputernerds.It'snothardtounderstandtheirmotivation:

Successfulphotographershaveanunusualcombinationofartisticeye,

dedicationtoademandingcraft,ahuckster'sknackforself-promotion,more

thanasmatteringofgoodbusinesssense,andanaffinityforthemechanicaland

electronicgadgetrythatmakeupourcamerasanddarkroomequipment.Digital

photographyis,ononelevel,justanotheroutrageouslypowerfulkindofphoto

gadget.Ifyoulikedautofocus,can'tlivewithoutautomaticbracketing,andthink

databacksarecool,you'lllovedigitalimaging.

Infact,ifyou'reanavidphotographer,yourinterestindigitalphotography

probablypredatespracticaldigitalphotographyitself,becauseaffordable

electronicmodelsthatcouldcompetewithtraditionalfilmcamerashavebeen

availableonlysincethebeginningofthismillennium.Thisisonetechnologyin

whichallofusaregettinginonthegroundfloor.Someyoungerphotographers

haveneverusedanythingelse.

Butforveteranphotographerswhohavelongedfordecadesforthekindof

capabilitiesthatdigitalphotographybringstothetable,thisisthebestofall

timestobetakingpictures.You'reprobablythehappiestclamonthebeachas

youwatchtechnologyfinallycatchuptoyourneeds.

However,it'sbeenalongandstrangetrip.Onlyaphotographercantruly

appreciatehowweirditisthattheabilitytocorrect,retouch,edit,and

manipulatedigitalpictureswithacomputerbecamecommonafulldecade

beforethetechnologytooriginateimagesindigitalformbecamepracticalfor

theaveragepicturetaker.HowisitthatwehadPhotoshopbackinthe1990s,but

hadtowaitforpracticaldigitalcamerasuntilthe21stcentury?Certainly,the

abilitytoeditconventionalphotographswithinimageeditorslikePhotoshop

(afterthephotosaredulyscannedanddigitized)isvaluablewhetherdigital

camerasarewidelyusedornot.Butdoesn'titmakemoresensetoeliminatethat



intermediatestep?Doesn'tdigitalimageeditingcryoutfordigitalphotos?

Figure1.1showswhatthePhotoshopinterfacelookedlikeroughly10yearsago

onaMacintoshQuadra650.Figure1.2showshowfarwe'vecome,withashot

ofthelatestversionrunningonaPentium-poweredPCthatoperatesroughly80

timesfaster.

Figure1.1.ThisversionofPhotoshopwasintroducedevenbefore

practicaldigitalcameraswereavailable.

[Viewfullsizeimage]



Figure1.2.Today,thelatestversionofPhotoshopCS2.0isready

foranythingyourdigitalcameracanproduce.

[Viewfullsizeimage]



Yet,whilePhotoshopisblossomingintoitsninthedition,PhotoshopCS2.0,and

otherpopularimageeditorslikePhotoshopElementsandPaintShopProgainin

popularity,we'rejustnowseeingaffordabledigitalcamerasthatcantrulydo

everythingaseriousphotographer'sfilmcounterpartcanhandle.You'reprobably

thinking"abouttime!"alongwithmillionsofotherpicturetakers.

Thisbookisgoingtodelvealittledeeperintodigitalphotographythanmanyof

thebooksyoumighthaveread.Unlikemostoftheotherbooksontheshelf,this

isaphotographers'guide,designedtoleveragethethingsyoualreadyknow

aboutphotographyasyouspreadyourwingsinthedigitalrealm.Thisfirst

chapterisintendedtobeanoverviewofdigitalphotographyandtechnologya

glimpsefrom50,000feetthatprovidesyouwithsomeperspectiveonwherewe

are,wherewe'regoing,andhowwegothere.

Thischapter,aswellasthisentirebook,isintendedforseriousphotographersat

alllevelsofthedigitalrealm,andcoversbothdigitalSLRsaswellasnon-SLR

models,includingpoint-and-shootcamerasandthoseusingelectronic

viewfinders.IfyourinterestsliewithdigitalSLRs,Ihopeyou'llcheckoutmy

companionvolume,MasteringDigitalSLRPhotography,alsofrom



Thomson/CourseTechnology,whichgoesintoalotmoredetailaboutthethings

dSLRusersneedtoknow.

YoumightnothaveseenthebackgroundinformationI'mgoingtopresentinthe

digitalcamerabooksyou'vereadprobablybecausetheauthorsweren't

photographers.Acomputerguruwhounderstandsmicroprocessorsandsoftware

applicationsmighthavenoclueastowhatmakesagreatimage.However,if

you'reseriousaboutphotography,youknowthatsimpleknowledgeofthe

mechanicsoftakingpicturesisn'tenough.Youmustalsohavetherighttools,

knowhowtheyarebestapplied,andunderstandhowtousethem.That'swhat

you'llbegleaningfromthisbook.

You'lllearnexactlyhowdigitalfreesustodothingswithimagesthatcouldonly

beaccomplishedbytediousworkandexperimentationwithconventionaltools.

Photographerswhohavedarkroomexperiencemighthavecombinedimages

withdoubleexposures,sandwichedtwoslidestogether,cross-processedchromes

incolor-negativedevelopingsolutions,orpushedsuper-fastfilmstoridiculous

exposureindexestogetaparticulareffect.Thesetechniquesusuallyinvolve

moreerrorthantrialwhenyou'reworkingwithconventionalfilms.Withadigital

camera,youcaninstantlyreshootapictureuntilyougettheresultsyouwant.

Thecomputerboththeoneonyourdesktopandtheonebuiltintoyour

cameragivesyouthefreedomtotweak,re-tweak,andstartoverifthefinal

resultsdon'tpleaseyou.Indeed,thereisawholelitanyoftricksthatcouldn'tbe

doneatallbeforetheintroductionofdigitalimaging.

Individualimagecomponentscanbeisolated,combinedwithothercomponents,

reversed,rebalanced,orremovedentirelywithbarelyatraceofwhathasbeen

doneremainingforthecasualeyetodetect.WecanrelocatetheGreatPyramid

ofEgypt,showElvisshakinghandswithaliensfromspace,orremovean

intrusivemother-in-lawfromabridalportrait.

Morethananythingelse,digitalphotographyisfun.Mostofus,eventhough

we'recapableofdoinggoodworkwithsimpleequipment,don'thesitatetotake

advantageofallthetoolsthatareavailable.So,itwasonlyamatteroftime

beforedigitalimagingstartedseducingphotographerswhopreviouslyhadno

intentionofusingcomputers.Ascamerasbecamemoreelectronicand

computerized,itwasalogicalnextsteptoincorporatescannedimages,

electronicretouching,andeventuallydigitallyoriginatedimagesintotheaverage



photographer'srepertoire.That'swhysomanyperfectlygoodphotographers

havefounditnecessarytobecomecomputernerds.



HowYouGotHere

Thepathtodigitalphotographyhasalmostasmanyroadsasthoseleadingto

Rome.Manyofyouprobablyfirstdiscoveredthejoysoffilm-based

photography.Perhapsyouyearnedtotranscendtheordinaryvacationphotograph

andbringbackpicturesthatwouldprovidememoriesthatwouldlastalifetime.

Or,youmighthavediscoveredphotographyasanartisticoutlet,eitherbecause

youlackedskillswithabrushorchiselorsimplysawimagesinyourheadthat

couldonlybemadetangiblethroughcreativepicturetaking.

Inmycase,Iwasawriterwithapassionforphotographyfirst,anddiscovered

whenIappliedforajobasareporterforourlocalnewspaperthattheyneeded

mybuddingskillsasaphotographermorethantheyneededadditionalnews

writers.Thefitprovedtobeagoodone,andafterturninginafewwell-crafted

three-andfour-pagecutlinesforsomeofmysolophotographyassignments,I

earnedmyfirsthyphen,asareporter-photographer.Ispentalmost10yearsasa

photojournalistbeforeIsatdowninfrontofmyfirstpersonalcomputer,soit's

safetosaythatconventionalphotographywasengrainedinmysystemlong

beforethefirstdigitalcamerasimpingedonmyconsciousness.

Photographyalsoattractsadherentswhoneverdreamedthey'donedaylove

peeringthroughaviewfinder.Youmightbeaneagercoginsomecorporate

wheel,whodiscoveredthatphotoscanspiceupyourPowerPointpresentations

orenhanceyourrésumé.Whatstartsasalarkmaybe,snapshootingatcompany

picnicscaneasilydevelopintoareputationastheonlystaffmemberwhoreally

understandsphotography.Youmightbeawebmasterlookingtoimproveyour

personalsiteorthatofyourorganization.Eventhemostdedicatedcomputer

nerdcandiscoverthejoysofgraphicsprocessing,andfromthere,itisonlya

shortsteptophotographyanddigitalphotography.

Nomatterhowyougothere,it'ssafetosayyou'rehooked.



HowtheTechnologyGotHere

Formillennia,textandpicturesweremoreorlessequals:Scribesilluminatedor

illustratedamanuscriptatthesametimethetextwasdrawn.Theonly

technologyinvolvedwas,say,aquillpenandthetoolsusedtosharpenit.When

bothtextandgraphicswerehand-drawn,ittookalittlelongertocreatean

illustration,but,astheysay,asketchisworthathousandwords.Untilthe

inventionofmovabletype,textandgraphicsmergedseamlessly,withneither

formofvisualcommunicationhavinga"technological"advantageoverthe

other.Ofcourse,manualmethodssharplylimitedaccesstovisualinformation,

unlessyouwereroyalty,rich,orworkedinaprofessionthatrequiredliteracy.

Thatbalancebetweentextandgraphicschangeddramaticallywhenmovable

typesimplifiedtheprintingofbooksabout500yearsago.Thedistributionof

textsuddenlybecameseveralordersofmagnitudeeasierthanthereproduction

ofimages.Movabletypelettextreachthemasses,butpicturesstillhadtobe

laboriouslycarvedaswoodcuts,engravedinsteel,orconvertedtohalftonedots

beforetheycouldbeprinted.Thetransmissionofwordsbytelegraphpredated

wirephotosandfaxmachinesbyroughlyacentury,andthefirst35yearsofthe

ComputerAgeweredominatedbytextandnumbers.Newspaperadvertisements

inthe1860swerebetterillustratedthanaccountsoftheCivilWar,andcomputer

artistsacenturylatersometimescreatedportraitsbyassemblingASCII

charactersintocrudemosaics(ifyou'veseensomeofthepinupsthatresulted,

you'llknowwhytheywereconsideredcrude).

It'sonlybeeninthepastfewyearsthatdigitalimaginghasprovidedthe

technologyweneedtomeldtextandpicturesseamlesslywithourdocuments,

computerpresentations,webpages,andotherelectronicmedia.

Theadvantagesofdigitalimagingaresimple:Ifyouhaveadigitalcamera,

computer,andprinter,youcancaptureimages,refineorretouchthem,and

distributethemthoughprintouts,e-mail,orwebpages.Youcanaccomplishall

thesethingsinthespanofafewminutesorhourswithoutrelyingonfilm

manufacturers,photofinishers,professionalretouchers,or,inmostcases,the

postalsystem.



Thedisadvantagesarevanishing.Digitalcamerasstillcostmorethanfilm

camerasofequivalentfeaturesandquality,butthecost"penalty"isbecoming

smallerandsmaller.Today,youcanpayafewhundreddollarsforagoodfilm

camera,orbuyadigitalcamerawiththesamequalitybutgreaterconvenience

forperhaps20to50percentmore.Digital"film,"whilealmostinfinitely

reusable,costsmorethanfilm,butmemorycardscanbepurchasedtodayfor

$20-50thatwillholdhundredsofimages.Computer-generatedprintsyoumake

athomearestillmorecostlythanthedrugstorekind,buttodayyourdrugstore

willbehappytomakethoseprintsforyouforaboutthesamepriceasmaking

printsfromfilm.

Asrecentlyastwocenturiesago,unlessyouhadmetarelativepersonallyor

camefromafamilywealthyenoughtohavecommissionedaportrait,you

probablydidn'tevenknowwhatyourancestorslookedlike.Yourown

grandfathermighthavebeenastrangertoyouunlessyouhadmethim

personally.Today,youcansnapapictureoftheoldgeezerwithyourdigital

cameraande-mailittoalong-lostrelativewhomightneverbeabletodropby

foravisit.Theaveragecomputerownertodaycandousefulthingswithimages

thatwerebeyondtheimaginationofthewealthiestroyaltyinthepast.

Eventhoughwe'recurrentlyimmersedinatransitionfromconventionalfilm

photographytodigitalphotography,thetwotechnologiesactuallyhavevery

littleincommon,exceptonanabstractlevel.Digitalphotographydidn'tevolve

fromfilmimaginganymorethanaudioCDsevolvedfromphonographrecords

ormagnetictapecassettes.Whilethetechnologiesservethesameneeds,their

originsareverydifferent.Traditionalphotographyhasitsrootsinchemical

technology,whichgaveusphotosensitivefilms,plates,andpapers.Digital

imagingcomesfromafoundationofelectronics(eventhoughdigitalsensorsare

createdchemically).Thechieftechnologicalconvergencebetweenthetwolies

intheopticalandexposuresystemsofcameras:Bothfilmanddigitalcameras

uselenses,viewfinders,andlensapertures.

Wecanskipthehistoryofconventionalphotographyentirely,andjumpahead

roughly100yearsto1951,whenBingCrosbyLaboratories(yes,thatBing

Crosby)developedthefirstvideotaperecordertoconvertliveTVimagestoa

formatthatcouldbestoredontomagnetictape.Afewyearslater,Ampex

marketedthefirstcommercialVTRforawhopping$50,000.AlthoughTV

camerashadbeenavailablepreviously,theabilitytosavethoseimages



permanentlyreallymarksthebeginningsofdigitalphotography.Videocameras

anddigitalcamerasgenerallyuseasensorcalledaCCD(chargedcoupled

device),developedin1970(althoughothertypesofsensorswillbeimportantin

thefuture).TheearlyVTRsaretrulythegranddaddiesofourpresentdaydigital

cameras.



WhichCameFirst?

Acasecanalsobemadeforscanners,firstdevelopedbyKodakinthemid-20th

century,asaprogenitorofthedigitalcamera.However,scannerscapture

informationline-by-lineoveraperiodoftimeandarelimitedtoobjectsthat

canbeplacedclosetothescanner'ssensor.Videosystemsalsoscan,buttake

only1/30thofasecond,andcangrabanythingtheeyeofthevideocameracan

see.



Truedigitalphotographycamelaterinstages,nudgedalongbyyourtaxdollars

atwork.Inthe1960s,NASAconvertedfromanalogtodigitalsignalsforthe

lunarmissionsthatmappedthesurfaceofthemoon,because,asyouprobably

know,analogsignalscanfadeinandout,whereasdigitalinformationcanbe

capturedvirtuallyerror-free.Thefirstheavy-dutyimageprocessingwas

developedinthisera,asNASAputthepowerofcomputertechnologytowork,

enhancingtheimagesreturnedbyitsvariousspaceprobes.TheColdWar,

repletewithspysatellitesandvarioussuper-secretimagingsystems,alsohelped

pushthedevelopmentofdigitalphotography.

Thefirstfilm-freeelectroniccamerawaspatentedbyTexasInstrumentsin1972.

OneofthepatentdrawingsforthissystemisshowninFigure1.3.Thechief

drawbackofthissystemwasthat,haditeverbeenproduced,itwouldhave

requiredviewingthestillphotosonatelevision.TVviewingwasalsoanoption

forthelaterSonyMavica,introducedinAugust,1981asthefirstcommercial

electroniccamera.However,theMavicacouldalsobeattachedtoacolorprinter.

Yet,eventheMavicawasn'tatruedigitalcamera;itwasmoreofavideocamera

thatwasabletocaptureanddisplayindividualframes.

Figure1.3.Thefirstfilmlesselectroniccamerawaspatentedby

TexasInstrumentsmorethan30yearsago.

[Viewfullsizeimage]



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