英语演讲-相机介绍.ppt

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1、Camera:ApowerfulmachineCanyouimagineaworldwithoutcameras?HowDoCamerasWork?First,closeyoureyes.Nowquicklyopenandshutthem.Whatdidyousee?Yousawanimage,or“picture,”fromyoursurroundings.Abasiccameraworksalotlikeyoureyes.Trythis:HowCamerasChangeTheWorldThecamerabroughtthewholeworldintopeople’shomesordina

2、rypeoplecouldaffordtohavesnapshotsofthemselvesThankstothemotion-picturecamera,wehavetelevisionandmovies.CamerasEverywhereApoint-and-shootcameraautomaticallyfocusesthelensandcontrolshowquicklytheshutteropensandcloses.CamerasEverywhereManybanks,stores,andschoolsusesecuritycamerastowatchwhatpeopleared

3、oing.CamerasEverywhereCamerasareimportanttoolsforscientists.Doctorsusetinycamerastolookinsidethehumanbody.CamerasonsatellitesorbitEarth,takingpicturesofweatherpatterns.Camerasbringuspicturesfromthedeepestoceans,theinsidesofvolcanoes,andevenofdistantgalaxiesinspace!HistoryTheforerunnertothephotograp

4、hiccamerawasthecameraobscura(暗箱).InthefifthcenturyBC,theChinesephilosopherMoTinotedthatapinholecanformaninvertedandfocusedimage,whenlightpassesthroughtheholeandintoadarkarea.SomeSignificantCamera1921KodakOpenedupCineKodak,used16mmmoviefilmSilvestriFlexicamVoigtländerBrillanttwin-lensreflexcameraCon

5、taxSof1949—theworld'sfirstpentaprismSLR1952VoigtlanderVitoIISomeSignificantCameraAsahiflexIIaof1955AsahiflexIIaof1955NikonF of1959—thefirst35mm systemcameraVoigtländerVitoretof19621988ASoviet-eraLOMOLC-AcameraCanonEOS300D,amodelthatsparkedthepopularityofconsumer-levelDSLRsTheFutureofCameraConvenien

6、ttocarryPhotoeditingNetworkshareThankYou