产品详细描述：ContinuingglobalexpansioninthevolumeandvarietyofHDproducti***placesunceasingdemandsforextendedflexibilityandcreativityinimagecreation.TheneedfordramaticallyincreasedtelephotocapabilitiesinHDlensestomeetthecreativeneedsofnaturalhistoryproduction,HDnewsgathering,stadiumcoverage,surveillance,housesofworshipwhilealsofacilitatinggreaterportabilityandmobilityonlocationledtothedesignoftheHJ18ex28Blens.Thisinnovativeultra-telephotolensprovidesa500mmfocalrange(1000mmusingthebuilt-in2xrangeextender)inacompactpackagethatweighsonly2.48kg(IRSEAtype).Despiteitsmodestsize,theoverallperformanceoftheHJ18ex28Bisremarkablyhigh–providingamaximumaperturecapabilityofF2.5,verygoodpicturesharpness,andtightcontroloverchromaticaberrati***.Eventhedigitaldrive-unitisnewlydevelopedtoprovidestreamlinedergonomicsandeaseofoperationthatfurtherempowerscameraoperatorshootingflexibility.(Newdriveisloadedwiththelensthathas‘A'attheendofitsmodelnamesuchas‘IRSEA',‘IASEA'.)MainFeaturesPortableUltra-TeleAchievea500mmtelephotoimagecapturewithahandheldHDlensandcamera.The2xextenderwilltakethisto1000mmopeningupdramaticpossibilitiesinwildlifeshooting,specialnewsevents,sportsandmanyotherapplicati***.ACompactandLightweightOpticalPowerhouseThegoalofproducingalightweighthandheldultra-telephotoHDzoomlenshasbeenrealizedintheHJ18ex28B.Measuringonly268.3mmlongandweighing2.48kg(IRSEAtype),thislensopensupentirenewcreativeimagingcapabilitiesformobilelocationshooting.HighopticalperformanceTheadoptionofnewopticalmaterialsandcontemporaryopticaldesigntechnologiesh***efacilitatedtheproductionofagroundbreakingportablelensthatsignificantlyaddstothecreativearsenal***ailabletotheHDproductioncommunities.Thenovel3-groupinnerfocussystemdesigninparticularwascentraltoachievingtheextratelephotorangewhilecontrollingmultipleopticalaberrati***.Highsharpnessandcontrastismaintainedoverthisimpressivefocalrange,whileachievingalightweightcompactphysicaldimensi***.NewErgonomicDriveUnitBesidestheexceptionalopticalperformance,anotherremarkablecharacterofthisnewlensisit’snewlydesigneddriveunit.Withthegoalofpursuingeaseofoperation,Canonhasreachedanewdesignbasedonhumanergonomics,refinedbyalongtermresearchandtesting.Ofcourse,alltheadvantagesfromthecurrente-HDxsDigitalDriveUnitsuchas"InformationDisplayforusercustomizesetting","RotaryEncoderforvirtualstudiointegrationandprecisecontrol"and"EnhancedDigitalFuncti***"areinheritedtothenewdriveunit.SeemoreinformationfromourFAQLensHJ18ex28BIRSEA/IASEAZoomRatio18xBuilt-inExtender2.0xRangeofFocalLength(withExtender)28~500mm56~1000mmMaximumRelativeAperture(withExtender)1:2.8at28~286mm1:4.9at500mm1:5.6at56~572mm(2.0x)1:9.8at1000mmAngularFieldofView(withExtender)4:3AspectRatio(8.8x6.6mm)18.0°x13.5°at28mm1.0°x0.8°at500mm9.0°x6.8°at56mm(2.0x)0.5°x0.4°at1000mm16:9AspectRatio(9.6x5.4mm)19.5°x11.0°at28mm1.1°x0.6°at500mm9.9°x5.6°at56mm(2.0x)0.6°x0.3°at1000mmMinimumObjectDistance(M.O.D)2.2m(10mmwithMacro)ObjectDimensi***atM.O.D.(withExtender)4:3AspectRatio(8.8x6.6mm)65.4x49.1cmat28mm3.8x2.9cmat500mm32.7x24.6cmat56mm(2.0x)1.9x1.5cmat1000mm16:9AspectRatio(9.6x5.4mm)71.1x40.0cmat28mm4.1x2.3cmat500mm35.6x20.0cmat56mm(2.0x)2.1x1.2cmat1000mmMacroYesSize(WxHxL)176.2x123.6x268.3mmWeight(Approx.)IRSEA2.48kg(5.47lbs)IASEA2.56kg(5.65lbs)OperationalAccessoriesFullservo:SS-41-IASD/SS-41-DSemiservo:MS-210D)