Cov neeg tsim khoom nyiam sim ua kom yooj yim rau koj thaum koj yuav khoom rau lub koob yees duab digital, tshwj xeeb tshaj yog los ntawm kev qhia qee qhov kev ntsuas ntawm lawv cov qauv, xws li cov nyiaj megapixel loj thiab qhov loj ntawm LCD npo.
Txawm li cas los xij, cov lej no tsis tas yuav qhia tag nrho zaj dab neeg, tshwj xeeb tshaj yog thaum saib lub ntsej muag zoom ntawm lub koob yees duab digital. Cov neeg tsim khoom ntsuas lub peev xwm zoom ntawm cov koob yees duab digital hauv ob qhov kev teeb tsa: optical zoom lossis digital zoom. Nws yog ib qho tseem ceeb kom nkag siab txog lub lens zoom vim tias ob hom zoom yog qhov sib txawv ntawm ib leeg. Hauv kev sib ntaus sib tua ntawm optical zoom vs. digital zoom, tsuas yog ib qho - optical zoom - yog qhov tseem ceeb rau cov kws yees duab.
Nrog rau cov koob yees duab digital feem ntau, lub lens zoom txav tawm sab nraud thaum siv, txuas mus rau lub koob yees duab lub cev. Qee lub koob yees duab digital, txawm li cas los xij, tsim qhov zoom thaum kho cov duab loj hauv lub cev lub koob yees duab.
Ntxiv mus nyeem kom pom cov ntaub ntawv ntxiv uas tuaj yeem pab koj nkag siab lub koob yees duab zoom lo ntsiab muag zoo dua.
YOptical Zoom
Optical zoom ntsuas qhov tseeb nce ntawm qhov ntev ntawm lub lens. Focal ntev yog qhov kev ncua deb ntawm qhov nruab nrab ntawm lub lens thiab cov duab sensor. Los ntawm kev txav lub lens kom deb li deb ntawm cov duab sensor hauv lub koob yees duab lub cev, qhov zoom nce vim tias qhov me me ntawm qhov xwm txheej cuam tshuam cov duab sensor, ua rau muaj qhov loj.
Thaum siv kho qhov muag zoom, qee lub koob yees duab digital yuav muaj qhov zoom zoom, txhais tau tias koj tuaj yeem nres ntawm txhua qhov chaw raws qhov ntev ntawm qhov zoom rau ib feem zoom. Qee lub koob yees duab digital yuav siv qhov tshwj xeeb nres raws qhov ntev ntawm qhov zoom, feem ntau txwv koj mus rau ntawm plaub thiab xya ib feem zoom txoj haujlwm.
Digital Zoom
Kev ntsuas digital zoom ntawm lub koob yees duab digital, muab tso rau hauv qhov tsis tseeb, tsis muaj nqis nyob rau hauv feem ntau qhov xwm txheej tua. Digital zoom yog lub tshuab uas lub koob yees duab tua cov duab thiab tom qab ntawd cog qoob loo thiab nthuav nws los tsim cov duab kos duab ze. Cov txheej txheem no yuav tsum tau nthuav dav lossis tshem tawm ib tus pixels, uas tuaj yeem ua rau cov duab tsis zoo.
Feem ntau koj tuaj yeem ua haujlwm sib npaug ntawm digital zoom nrog cov duab-editing software ntawm koj lub computer tom qab koj tua cov duab. Yog tias koj tsis muaj sijhawm los yog nkag mus rau kev kho cov software, koj tuaj yeem siv digital zoom los tua ntawm qhov kev daws teeb meem siab thiab tom qab ntawd tsim cov khoom tsim los ntawm kev tshem cov pixels thiab cropping cov duab mus rau qhov kev daws teeb meem qis dua uas tseem ua tau raws li koj xav tau.. Pom tseeb, qhov txiaj ntsig ntawm digital zoom tsuas yog txwv rau qee qhov xwm txheej.
Kev nkag siab zoom ntsuas
Thaum saib cov lus qhia tshwj xeeb rau lub koob yees duab digital, ob qho tib si kev ntsuas qhov muag thiab digital zoom tau teev tseg raws li tus lej thiab "X," xws li 3X lossis 10X. Tus lej loj dua txhais tau tias muaj peev xwm nthuav dav dua.
Nco ntsoov tias tsis yog txhua lub koob yees duab "10X" qhov ntsuas qhov muag pom zoo ib yam. Cov neeg tsim khoom ntsuas qhov kho qhov muag zoom los ntawm ib qho kawg ntawm lub lens lub peev xwm mus rau lwm qhov. Hauv lwm lo lus, "multiplier" yog qhov sib txawv ntawm qhov tsawg tshaj plaws thiab qhov loj tshaj plaws focal ntev ntsuas ntawm lub lens. Piv txwv li, yog tias 10X optical zoom lens ntawm lub koob yees duab digital muaj qhov ntev focal tsawg kawg nkaus ntawm 35mm, lub koob yees duab yuav muaj 350mm qhov ntev tshaj plaws focal ntev. Txawm li cas los xij, yog tias lub koob yees duab digital muaj qee lub peev xwm dav dav ntxiv thiab muaj qhov tsawg kawg nkaus 28mm sib npaug, ces 10X optical zoom tsuas yog muaj qhov ntev tshaj plaws ntawm 280mm.
Lub focal ntev yuav tsum tau teev nyob rau hauv lub koob yees duab specifications, feem ntau nyob rau hauv ib hom ntawv zoo li "35mm zaj duab xis sib npaug: 28mm-280mm." Feem ntau, 50mm lens ntsuas yog suav tias yog "ib txwm," uas tsis muaj qhov loj me thiab tsis muaj peev xwm dav dav. tus lej ntawm lub lens mus rau lub lens. Qee cov tuam txhab lag luam yuav tshaj tawm qhov tseeb qhov ntev ntawm qhov sib npaug ntawm 35 hli sib npaug, yog li nws tuaj yeem ua rau me ntsis ruam yog tias koj tsis saib tus lej raug.
Hloov pauv Lenses
Cov koob yees duab digital tsom rau cov neeg pib tshiab thiab cov neeg siv nruab nrab feem ntau tsuas yog muab lub lens built-in. Feem ntau cov koob yees duab digital SLR (DSLR), txawm li cas los xij, tuaj yeem siv cov lo ntsiab muag sib hloov. Nrog lub DSLR, yog tias koj thawj lub lens tsis muaj lub kaum ntse ntse lossis zoom qhov koj xav tau, koj tuaj yeem yuav cov lo ntsiab muag ntxiv uas muab ntau qhov zoom lossis zoo dua qhov kev xaiv dav dav.
DSLR koob yees duab yog kim dua li cov qauv taw tes thiab tua, thiab lawv feem ntau yog tsom rau cov kws yees duab nruab nrab lossis qib siab.
Feem ntau DSLR lo ntsiab muag yuav tsis suav nrog tus lej "X" rau kev ntsuas zoom. Hloov chaw, qhov ntev focal yuav tsuas yog teev, feem ntau yog ib feem ntawm lub npe ntawm DSLR lens. DIL (digital interchangeable lens) koob yees duab, uas yog mirrorless interchangeable lens koob yees duab (ILC), kuj siv lo ntsiab muag uas teev los ntawm lawv focal ntev, tsis yog ib tug X zoom tooj.
Nrog lub koob yees duab hloov pauv hloov tau, koj tuaj yeem suav qhov ntsuas qhov muag pom koj tus kheej los ntawm kev siv tus lej lej yooj yim. Siv lub siab tshaj plaws focal ntev uas lub interchangeable zoom lens ua tiav, hais 300mm, thiab faib nws los ntawm qhov tsawg kawg nkaus focal ntev, hais 50mm. Hauv qhov piv txwv no, qhov sib npaug optical zoom ntsuas yuav yog 6X.
Qee Zoom Lens Drawbacks
Txawm hais tias xaiv lub koob yees duab taw tes thiab tua nrog lub qhov muag pom loj loj yog qhov xav tau rau ntau tus kws yees duab, nws qee zaum nthuav tawm ob peb qhov teeb meem me.
- Noise: Qee tus pib-theem, pheej yig lub koob yees duab raug kev txom nyem los ntawm cov duab tsis zoo vim lub suab nrov thaum lub lens txuas mus rau qhov siab tshaj plaws zoom. Lub koob yees duab lub suab nrov yog ib txheej ntawm cov pixels stray uas tsis sau kom raug, feem ntau tshwm sim raws li cov npoo ntshav hauv daim duab.
- Pincushioning: Qhov siab tshaj plaws kuj qee zaum ua rau pincushioning, uas yog qhov tsis sib xws qhov twg sab laug thiab sab xis ntawm daim duab tshwm stretched. Kab rov tav tshwm me ntsis nkhaus mus rau nruab nrab ntawm tus ncej. Ib zaug ntxiv, qhov teeb meem no feem ntau yog txwv rau qib pib, pheej yig lub koob yees duab nrog lub ntsej muag zoom loj.
- Lub sijhawm teb qeeb qeeb: Thaum siv qhov kev nthuav dav siab tshaj plaws, lub sijhawm kaw lub sijhawm qee zaum qeeb, uas yuav ua rau pom qhov muag tsis pom. Koj kuj tuaj yeem nco tau ib daim duab uas tshwm sim vim qhov kev teb qeeb qeeb. Nws tsuas yog siv lub koob yees duab digital ntev dua los tsom rau cov duab ntawm qhov chaw zoom siab tshaj plaws, uas piav qhia lub sijhawm teb qeeb qeeb. Cov teeb meem zoo li no tau nthuav dav thaum tua ntawm qhov siab tshaj plaws zoom hauv lub teeb qis.
- Yuav tsum muaj lub koob yees duab: Kev siv lub lens ntev tuaj yeem ua rau lub koob yees duab nce ntxiv. Qee lub koob yees duab digital tuaj yeem kho qhov teeb meem no los ntawm kev txhim kho cov duab. Koj tseem tuaj yeem siv lub koob yees duab los tiv thaiv cov duab tsis pom los ntawm lub koob yees duab co.
Tsis txhob dag
Thaum qhia txog qhov tshwj xeeb ntawm lawv cov khoom lag luam, qee cov tuam txhab lag luam yuav muab cov digital zoom thiab kho qhov muag zoom ntsuas, tso cai rau lawv nthuav tawm cov lej loj sib xyaw ua ke nyob rau pem hauv ntej ntawm lub thawv.
Koj, txawm li cas los xij, yuav tsum tau saib tsuas yog tus naj npawb kho qhov muag pom, uas tej zaum yuav raug teev nyob rau hauv ib lub ces kaum ntawm sab nraum qab ntawm lub thawv, nrog rau tus tswv ntawm lwm tus lej tshwj xeeb. Tej zaum koj yuav tau ua me ntsis tshawb nrhiav kom pom qhov ntsuas qhov muag pom ntawm ib qho qauv.
Thaum lub koob yees duab digital zoom lo ntsiab muag, nws them los nyeem cov ntawv zoo. Nkag siab lub lens zoom, thiab koj yuav ua tau ntau tshaj plaws ntawm koj lub koob yees duab digital yuav.
