technology of photography...• roll film made possible a new kind of camera - inexpensive, light...
TRANSCRIPT
TechnologyofPhotographyClaudiaJacquesdeMoraesCardoso
Based on Alex Sirota http://iosart.com/photography-art-or-science
CameraObscura
Camera Obscura, Georg Friedrich Brander (1713 - 1785), 1769
LightSensitiveMaterials• Afterthecameraobscurahadbeeninventedandit’suse
widelypopularized,manydreamtofcapturingtheimagesobtainedbythecameraobscurapermanently.
• Forhundredsofyearsbeforephotographywasinvented,peoplehadbeenawarethatsomecolorsarebleachedinthesun,buttheyhadmadelittledistinctionbetweenheat,airandlight.
• In1727,JohannHeinrichSchulze(1687-1744),aGermanscientistfoundthatsilversaltsdarkenedwhenexposedtosunlightandpublishedresultsthatdistinguishedbetweentheactionoflightandheatuponsilversalts.
• Evenafterthisdiscovery,amethodwasneededtohaltthechemicalreactionsotheimagewouldn’tdarkencompletely.
A Simplified Schematic Representation of the Silver Halide Process
FirstPermanentPicture
JosephNicephoreNiepce(1765-1833),aFrench
inventor,wasexperimentingwithcameraobscuraand
silverchloride.
• In1826,heturnedtobitumenofJudea,akindofasphaltthathardenedwhenexposedtolight.
• Niepcedissolvedthebitumeninlavenderoilandcoatedasheetofpewterwiththemixture.
• Heplacedthesheetinthecameraandexposeditforeighthoursaimedthroughanopenwindowathiscourtyard.
• Thelightformingtheimageontheplatehardenedthebitumeninbrightareasandleftitsoftandsolubleinthedarkareas.
• Niepcethenwashedtheplatewithlavenderoil,whichremovedthestill-softbitumenthathadn’tbeenstruckbylight,leavingapermanentimage.
• Niepcenamedtheprocessheliography-Greek,helios-“sun”,graphos-“drawing”.
View from the Window at Le Gras, Joseph Nicephore Niepce, 1826
Daguerreotypes
NewsofNiepce’sworkhadreachedanotherFrenchman,
LouisJacquesMandeDaguerre(1787-1851)whohadbeenexperimentingtocapturecameraobscuraimages.
• In1829NiepceandDaguerrebecamepartners,apartnershipwhichlasteduntilNiepce’sdeathin1833.
• Daguerreperfectedtheprocess,reducingtheexposuretimefromeighthourstohalfanhour.Hefoundthatanimagecouldbemadepermanentbyimmersingitinsalt.
• In1839heannouncedthenewprocesswhichhenamed“daguerreotype”beforetheFrenchAcademy.
• AFrenchnewspaperpraisedtheprocess:“Whatfinenessinthestrokes!Whatknowledgeofchiaroscuro!Whatdelicacy!Whatexquisitefinish!…Howadmirablyaretheforeshorteningsgiven:thisisNatureitself!”
• Almostimmediatelyaftertheannouncement,hundredsofdaguerreotypestudioswereopenedtoprovide“SunDrawnMiniatures”tothepublic.
• By1853anestimatedthreemilliondaguerreotypesperyearwereproducedintheUnitedStatesalone.
StillLifeinStudio,LouisJacquesMandeDaguerre,1837Theearliestknowndaguerreotype
DaguerreotypeofCoupleHoldingDaguerreotype,UnknownArtist,1850
EmilyDickinsonat17,UnknownArtist,1847
FollowingAchievements• Daguerreotypeshadonemajordrawback,therewasnowayof
producingcopiesoftheoriginalplate.• InJune1940,anEnglishamateurscientistHenryFoxTalbot
(1800-1877)announcedatechniquewhichbecamethebasisofmodernphotography.Hecalledit"calotype"(Greekfor"beautifulpicture").
• ThegreatadvantageofTalbot'smethodwasthattheprocessinvolvedbothanegativeandapositive.Thenegativeimage,thecalotype,wasrepeatableindefinitelyinapositiveprint,finallyallowingmultipleprints.
• By1880,aconvenient“dryplate”processwasdeveloped,allowingveryfastdevelopmentandopeningthefieldtothegeneralpublic.
TheOpenDoor,WilliamHenryFoxTalbot,1843
XieKitchinwithUmbrella,LewisCarroll,1875
RollFilm
MuchofthecreditforpopularizingphotographygoestoGeorgeEastman(1854-1932).HebeganasabankclerkinRochester,NY,andbuilthisEastmanKodakCompanyintoagreatenterpriseitistoday.
• In1884Eastmaninventedtheequipmenttomassproduceroll
film.“Eastnman’sAmericanFilm”wasarollofpapercoatedwiththingelatinemulsion.
• Rollfilmmadepossibleanewkindofcamera-inexpensive,lightandsimple-thatmadeeveryoneapotentialphotographer.
• Intheearlyyearsofthecompany,filmbasewasmanufacturedandcoatedonlongglasstables.
RoyalGoldKodakfilm,1994
KodakCamera• Kodakcamerawasintroducedin1888.Theirsloganwas
“Youpushthebutton,wedotherest”.• TheKodakcamerabecameaninternationalsensation
almostovernight.• Anewphotographicera,ofsimplelightcamerasandeasy
tohandlerollfilmhadbegun.
ThefirstKodakcamera,1888
Kodakcameraadvertisement,1890
GeorgeEastmanwithaKodakcamera,Fredrick
Church,1890
Color-FirstSteps
Maxwelldevisedawaytorecreatethecolorsofatartanribbon.Hehadthreenegativesoftheribbonmade,eachthroughadifferentcolorfilter-red,greenandblue.
Oneofthefirstsuccessesincolorphotographywasdemonstratedin1861bytheScottishphysicistJamesClerkMaxwell(1831-1879).
• Positiveblackandwhitetransparenciesweremadeofthethreenegatives.Whileprojectedsuperimposedthoughthreecolorfilterslikethoseonthecamera,thethreepositivesproducedanimageoftheribboninit’soriginalcolors.
• Thistechniqueiscalled“additivecolormixing”.Colorsareproducedbyaddingtogethervaryingamountsofred,greenandblue.
Maxwell’startanribbon
SubtractiveColorMixing
SubtractiveColorMixing
• In1869,LouisDucosduHauron(1837-1920)andCharlesCros(1842-1888),twoFrenchmanworkingindependentlyannouncedtheirresearchonsubtractivecolormixing.
• Insubtractivecolormixing,whichisthebasisformoderncolorphotography,colorsarecreatedbycombiningcyan,magentaandyellowdyes(thecomplementsofred,greenandblue).Thedyesaresubtractcolorsfrom“white”lightthatcontainsallcolors.
LouisDucosduHauronLeavesandFlowerPetals,1869
CommercialColorPhotographyThefirstcommerciallysuccessfulcolorprocesswasdevelopedbyAntoineandLouisLumiere,twoFrenchbrothers,in1907.Itwasanadditiveprocesscalled“Autochrome”.
Jean-BaptisteTournassoud(1866-1951),Autochrome,Early20thcentury.
Autochrome
• Aglassplatewascoveredwithtinygrainsofpotatostarchdyedred-orange,greenandvioletinalayeronlyonestarchgrainthick.
• Thenalightsensitiveemulsionwasadded.Lightstrucktheemulsionafterpassingthroughthecoloredgrains.Theemulsionbehindeachgrainwasexposedbylightfromthescenethatwasthesamecolorasthatgrain.
• Theresultwasafullcolortransparency.
Jean-BaptisteTournassoud,Autochrome,Early20thcentury.
AutochromelandscapeofMadeirabyMissSarahAngelinaAcland,1908-15
Kodachrome• Asubtractivecolorprocesscalled
kodachromemadecolorphotographypractical.
• ItwasperfectedbyLeopoldMannes(1899-1964)andLeopoldGodowsky(1900-1983),twomusiciansandamateurphotographicresearchers.
• TheircollaborationwithEastmanKodakscientistsledtotheintroductionofKodachromein1935.Kodachromewasasinglesheetoffilmcoatedwiththreelayersofemulsion,eachsensitivetooneprimarycolor(red,greenandblue).Asingleexposureproducedacolorimage.
1935
2000
LuisMardenCareerCollage,SarahLeen
LuisMarden,agreatphotographerworkingfortheNationalGeographicSocietywasoneofthefirstpioneersoftherevolutionarynewfilm.
Party-maskwithShells,PaulOuterbridge,1936
DigitalPhotography
• Inthemid1970s,Kodakandothercompaniesbeganinvestigatingfilmlesstechnologiesthatcouldcaptureimageswithsolidstatecircuitry
• In1986,Kodaksucceededincreatingasensorthatcouldrecord1.4millionpictureelements,ormegapixels.
• Inthe1990sthefirstdigitalcamerasappearedforcommercialuse.
KODAKPROFESSIONALDCS760DigitalCamera,6millionpixels,2001
• Thebigdifferencebetweentraditionalfilmcamerasanddigitalcamerasishowtheycapturetheimage.
• Insteadoffilm,digitalcamerasuseasolid-statedevicecalledanimagesensor,usuallyacharge-coupledevice(CCD).
• Onthesurfaceofeachofthesefingernail-sizedsiliconchipsisagridcontaininghundredsofthousandsormillionsofphotosensitivediodescalledphotosites,photoelements,orpixels.Eachphotositecapturesasinglepixelinthephoto-graphtobe.
Animagesensorsitsagainstabackgroundenlargementofitssquarepixels,eachcapableof
capturingonepixelinthefinalimage