To taub qhov txawv ntawm Nrov ncej thiab Qoob loo Sensors
Ib qho ntawm cov teeb meem tseem ceeb tshaj plaws thaum kho kom tus DSLR yog to taub qhov sib txawv ntawm cov ncej thiab cropped thaij duab. Thaum koj siv lub koob yees duab compact, qhov no yuav tsis yog ib qho uas koj xav tau tiag tiag, raws li lub ntsiab muag built-in yog tsim los ua qhov txawv tsis paub meej. Tab sis thaum koj pib saib mus rau hauv kev yuav ib lub DSLR, kev to taub cov ncej tag nrho thiab qoob loo sensor sib piv yuav vastly pab koj.
Tas nrho cov ncej
Rov qab nyob rau hauv lub hnub ntawm zaj duab xis photography, muaj tsuas yog ib tus sensor loj nyob rau hauv 35 hli photography: 24 hli x 36mm. Yog li ntawd, thaum tib neeg hais txog "tha xim kab xev" cov koob yees duab hauv digital photography, lawv tham txog 24x36 sensor loj.
Hmoov tsis, thawm lub koob thaij duab kuj yuav tuaj yeem tuaj nrog tus nqi txhim khu loj. Tus nqi qiv tshaj plaws Canon lub koob yees duab, piv txwv li, yog ob peb txhiab daus las. Feem ntau cov kab xev thaij duab yog siv los ntawm cov kws pab tswv yim, leej twg xav tau nta ntxiv. Cov kev xaiv yog "cropped frame" cameras, los yog "crop sensor" koob yees duab. Cov no muaj nqi ntau dua nqe, uas ua rau lawv txaus nyiam rau cov uas pib nrog DSLRs.
Cropped ncej
Lub voj voog los yog lub caws pliav yog zoo ib yam li qhov nruab nrab ntawm daim duab thiab muab pov tseg sab nraud. Li ntawd, yeej tseem zoo, koj nyob nraum sab laug nrog cov duab me ntsis thinner dua li qub - zoo ib yam li cov duab ua yeeb yam luv luv nyob APS. Qhov tseeb, Canon , Pentax thiab Sony feem ntau yog xa mus rau lawv cov khoom siv qoob loo ua "APS-C" koob yees duab. Tsuas yog qhov teeb meem xwb, Nikon ua tej yam txawv. Nikon tus ncej thaij duab hauv qab lub moniker ntawm "FX," thaum nws cropped ncej cameras yog hu ua "DX." Thaum kawg, Olympus thiab Panasonic / Leica siv qhov sib txawv me ntsis ntawm lub npe hu ua Four Thirds system.
Cov qoob loo ntawm tus sensor nws txawv me ntsis ntawm cov tuam ntxhab thiab. Feem ntau cov khw muag khoom 'cov qoob loo yog me tshaj li ib kab xev thaij duab los ntawm ib tus nqi 1.6. Txawm li cas los, Nikon qhov ratio 1.5 thiab Olympus 'ratio 2.
Lo ntsiab muag
Ntawm no yog qhov sib txawv ntawm qhov sib txawv thiab cov kab txha qaib tiag tiag tuaj rau hauv kev ua si. Nrog kev yuav khoom ntawm ib lub koob yees duab DSLR los ntawm lub sijhawm los mus yuav ib tus tswv tsev tseemceeb (muab koj cov nyiaj). Yog tias koj tuaj ntawm ib lub koob yees duab hauv keeb kwm yav dhau, koj yuav twb muaj ib lub party ntawm cov kev sib tshuam siv laub ntawm kev sib nraus. Tab sis, thaum siv lub koob yees duab qoob loo, koj yuav tsum nco ntsoov tias lub focal ntev ntawm cov lo ntsiab muag yuav hloov. Piv txwv li, nrog cov koob yees duab Canon, koj yuav tsum muab lub focal ntev ntev li ntawm 1.6, raws li tau hais los saum no. Yog li, ib tug 50mm standard lens yuav dhau los ua 80mm. Qhov no yuav ua tau kom zoo dua thaum nws tuaj cuag telephoto lo ntsiab muag, li koj mam li tau txais cov dawb millimeters, tiam sis lub sab nraud yog qhov lem-angle lo ntsiab muag yuav ua tus qauv lo ntsiab muag.
Cov kws kho mob tau tuaj nrog daws cov teeb meem no. Rau Canon thiab Nikon, leej twg los ua cov duab tha xim, cov lus teb tau tsim los tsim cov kab kev los ntawm cov koob yees duab tshwj xeeb rau cov koob yees duab digital - EF-S ntau rau Canon thiab DX ntau rau Nikon. Cov lo ntsiab muag muaj xws li ntau lub dav-angle lo ntsiab muag uas, thaum loj hlob, tseem cia rau lub dav dav pom. Piv txwv li, ob lub tuam txhab tsim lub lens zoom uas pib ntawm 10mm, yog li muab qhov tseeb focal ntev ntawm 16 hli, uas yog tseem tsis tshua muaj qhov dav-kaum lub lens. Thiab cov lo ntsiab muag no kuj tau tsim los txo cov teebmeem thiab vignetting ntawm cov npoo ntawm daim duab. Nws tseem yog tib zaj dab neeg nrog cov neeg ua lag luam uas tsim cov khoom tshwj xeeb tshaj plaws rau cov koob yees duab sensor, raws li lawv lub ntsiab muag tau tsim los khiav ntawm cov tshuab cov koob yees duab.
Puas Muaj Qhov Sib Txawv Ntawm Hom Lenses?
Muaj qhov sib txawv ntawm qhov lo ntsiab muag, tshwj xeeb tshaj yog tias koj yuav mus rau hauv lub tshuab Canon lossis Nikon. Thiab cov tuam txhab ob lub lag luam no muaj ntau yam kev siv cov koob yees duab thiab lenses, yog li ntawd nws yog qhov zoo tshaj plaws uas koj yuav nqis peev pab rau hauv ib qho ntawm lawv. Thaum lub digital lo ntsiab muag yog qhov sib tw heev, qhov zoo tshaj ntawm cov optics xwb tsis zoo li qhov zoo li zaj duab xis thawj lo ntsiab muag. Yog tias koj tab tom saib siv koj lub koob yees duab rau kev yees duab yooj yim, ces koj yuav tsis pom qhov txawv. Tab sis, yog tias koj tab tom nrhiav kom paub txog koj tus yees duab, ces nws tsim nyog nqis peev ntau hauv cov lo ntsiab muag.
Nws kuj tseem yuav tsum tau sau tseg tias Canon lub EF-S lo ntsiab muag yuav tsis ua hauj lwm txhua lub sijhawm ntawm lub tuam txhab tha xim kab xev. Nikon DX lo ntsiab muag yuav ua haujlwm rau nws cov kab xev thev naus laus zis, tiam sis yuav tsis muaj kev daws teeb meem los ntawm kev ua li ntawd.
Hom Hom Yog Dab Tsi Rau Koj?
Cov duab tha xim tas nrho yog siv koj lub peev xwm los siv lo ntsiab muag ntawm lawv cov focal ntev, thiab lawv tshwj xeeb yog ci hauv lawv lub peev xwm los tiv thaiv nrog shooting ntawm ISOs dua. Yog hais tias koj tua ntau heev nyob rau hauv ntuj thiab tsawg lub teeb, ces koj yuav undoubtedly nrhiav qhov no tseem ceeb. Cov neeg uas tua cov vaj tsev thiab cov duab thaij duab tseem xav xav kuaj kom paub cov duab thaij duab zoo li cov duab zoo thiab dav-lens zoo yog tseem nyob deb dhau.
Rau cov xwm, cov tsiaj qus, thiab cov neeg muaj kev lom zem ua si, ib tus sensor cropped yuav ua kom paub ntau dua. Koj tuaj yeem coj kom zoo dua cov focal ntev muaj los ntawm ntau cov duab thiab cov koob yees duab no feem ntau muaj kev ceev ceev tas mus li. Thiab, thaum koj yuav tau xam focal ntev, koj mam li tuav cov thawj lub aperture ntawm lub lens. Yog li, yog tias koj muaj 50mm lens tsau uas yog f2.8, ces nws yuav tswj lub aperture txawm nrog lub magnification rau 80mm.
Ob leeg tawm tswv yim muaj lawv txoj haujlwm. Cov kab xev thev duab loj dua, hnyav dua, thiab kim kim. Lawv muaj ntau qhov kev pab rau cov tub txawg, tab sis neeg feem coob yuav tsis tshua xav tau cov qauv no. Tsis txhob raug kev dag ntxias los ntawm tus neeg muag khoom uas hais rau koj tias koj xav tau lub koob yees duab kim overly. Ntev npaum li koj hais cov lus qhia yooj yooj yim hauv siab, koj yuav tsum paub zoo tias yuav ua rau qhov koj xav tau.