Lub koob yees duab lens lim yog ib daim iav ntxiv (lossis qee zaum yas) uas tau teeb tsa rau ntawm qhov kawg ntawm lub koob yees duab lens (qhov kawg uas ntsib cov ntsiab lus) los hloov lub teeb uas taug kev los ntawm lub lens mus rau cov duab sensor. Ntawm DSLR koob yees duab, lub lens lim tau siv los ua kom tiav ntau yam teebmeem. Nov yog yam koj yuav tsum paub txog ntau hom kev yees duab lim.
Lens Filter yog dab tsi?
Lub koob yees duab lens lim tuaj yeem pom tseeb, grey, kawm tiav, lossis ntau yam xim sib txawv. Lawv tau siv los hloov lub teeb uas taug kev los ntawm lub lens mus rau cov duab sensor, thiab lawv tau siv rau ntau yam teebmeem.
Thaum pib, cov ntxaij lim dej yees duab tau siv hauv kev yees duab thaij duab los txhim kho kev yees duab dub thiab dawb. Los ntawm kev ntxiv cov ntxaij lim dej sib txawv, tus kws yees duab tuaj yeem ntxiv qhov tob, txhim kho qhov sib piv, thiab txo lub teeb ci uas tuaj yeem ua rau cov duab puas.
Cov ntxaij lim dej niaj hnub tseem ua haujlwm nrog DSLR koob yees duab, tab sis ntau lub koob yees duab DSLR muaj cov yam ntxwv ua rau hauv hom kev tua, teeb tsa lub koob yees duab, thiab txawm tias nyob rau hauv cov khoom siv tiag tiag ntawm cov khoom siv uas ua haujlwm ntau yam. Yog li, nws tsis yog qhov txawv txav rau cov kws yees duab digital siv cov ntxaij lim dej rau kev tsim kho kom zoo thiab hloov pauv rau 'tus qauv' duab.
Hom Lub Koob Yees Duab Lens Lim
Lens lim siv ob hom: square lossis round. Square cov ntxaij lim dej yog tsim los plam mus rau hauv ib lub mount uas screws mus rau pem hauv ntej ntawm lub koob yees duab lens, tam sim ntawd nyob rau hauv pem hauv ntej ntawm lub lens sab nrauv. Tom qab ntawd, koj tuaj yeem xaiv qhov lim koj xav siv, plam nws mus rau hauv lub lim mount, thiab pib thaij duab koj qhov kev kawm.
Square lub koob yees duab lim tuaj yeem pheej yig dua li cov ntxaij lim dej puag ncig, vim tias ib txheej lim tuaj yeem siv nrog ntau qhov ntau thiab tsawg ntawm lo ntsiab muag. Cov ntxaij lim dej square kuj tau txiav txim siab los ntawm qee tus kws yees duab kom ua tau ntau yam, vim tias koj tuaj yeem tso lub lim mount txuas rau koj lub koob yees duab thiab ntxiv lossis tshem cov lim raws li xav tau.
Hom ntau hom lens lim uas koj yuav ntsib yog cov lim lim. Cov ntxaij lim dej no ntsia hlau rau pem hauv ntej ntawm lub koob yees duab lens (xav tias muaj cov xov xov ntawm lub lens- ob peb lub lens DSLR tsis muaj cov xov no).
Qhov teeb meem koj yuav ntsib nrog cov lim dej no yog tias koj xav tau qhov sib txawv rau txhua qhov sib txawv me me uas koj muaj. Piv txwv li, yog tias koj muaj 35mm lens uas muaj 57mm pem hauv ntej nplhaib, koj yuav tsum muaj 57mm lim. Yog tias koj ntxiv lub lens 18mm rau koj cov khoom siv uas muaj 67mm pem hauv ntej nplhaib, ces koj yuav tsum tau yuav lwm txheej lim uas yuav haum rau lub nplhaib loj dua.
Ib txoj hauv kev uas qee tus kws yees duab tau txais los ntawm kev yuav ntau lub thawv lim dej yog yuav cov lim dej uas haum rau lub lens loj tshaj plaws uas lawv muaj, thiab tom qab ntawd siv lub nplhaib nce qib los tsim cov lo ntsiab muag me me kom lawv haum. Qhov no yog ua tiav los ntawm stacking lim rings-qhov tseem ceeb screwing lawv ua ke kom txog thaum muaj qhov kawg uas haum lub koob yees duab lens thiab qhov kawg uas haum rau lub lens loj dua.
Txawm hais tias koj xaiv siv cov ntxaij lim dej square lossis round lens, koj tuaj yeem pom ntau yam ntawm cov ntxaij lim dej no, txhua tus ua nws txoj haujlwm. Piv txwv li, ib daim ntawv qhia koj yuav tau txais thaum ntxov yog ib txwm siv lub lim UV (ultra-violet) lim.
UV cov ntxaij lim dej yuav tsum pab txo qis hazy lossis grey-ish cam khwb cia ntawm cov duab, thiab qee tus kws yees duab khaws ib qho txuas rau lawv lub lens txhua lub sijhawm los pab tiv thaiv lub lens. Txawm li cas los xij, feem ntau cov koob yees duab DSLR ntawm kev ua lag luam muaj cov txheej txheem los tiv thaiv qhov no los ntawm qhov tshwm sim. Yog li, qhov tseeb, UV lim feem ntau tsis tsim nyog.
Ib txoj cai dav dav ntawm tus ntiv tes xoo hauv kev yees duab yog: lub iav ntau koj muab tso rau nruab nrab ntawm cov duab sensor thiab cov duab, qhov ntau yog qhov yuam kev. Ntxiv lwm txheej iav tuaj yeem txo cov teeb pom kev zoo uas ncav cuag lub sensor thiab ua rau cov duab tsaus dhau. Cov lim ntxiv ntawd tseem tuaj yeem ua kom paub ntau tus tswv tsev ntawm lwm cov teebmeem uas tsis tshwm sim thaum koj tsis siv nws, yog li nws ib txwm siv qee qhov kev sim tshuaj thaum ntxiv cov lim tshiab kom ntseeg tau tias koj tau txais qhov zoo li koj tab tom sim. ua kom tiav.
Cov lim dej yees duab siv dab tsi?
Ntxiv rau cov lim UV uas tau hais dhau los, muaj ob peb hom kev lim dej siv nrog ob lub koob yees duab digital thiab zaj duab xis. Lwm hom lens lim muaj xws li:
- Polarizing lim
- ND (nruab nrab ntom ntom) lim
- Variable lossis Circular ND Lim (tseem hu ua Graduated lossis Gradient filters)
- xim lim
Nrog tag nrho cov lim dej sib txawv no, nws tuaj yeem tsis meej pem txog hom lim yuav tsum siv rau yam xwm txheej twg. Nov yog ib qho kev ceev ceev ntawm txhua hom lim siv rau:
- Polarizing: Ntau yam xws li looj tsom iav dub polarizing, cov ntxaij lim dej polarizing tuaj yeem pab txo qhov kev xav thiab txhim kho cov xim ntawm cov duab. Qhov tsis zoo ntawm cov lim polarizing, txawm li cas los xij, yog tias lawv tuaj yeem ntxuav tawm saum ntuj, uas txhais tau tias koj yuav tsis tau txais qhov tob feem ntau cuam tshuam nrog huab zoo meej. Polarizing cov ntxaij lim dej yog qhov zoo rau kev txo cov dej glare, thiab feem ntau siv hauv toj roob hauv pes thiab sab nraum zoov yees duab.
- ND (Neutral Density) Lim: Lub hom phiaj ntawm ND lim yog txhawm rau txo cov teeb pom kev zoo uas nkag mus rau lub lens ntws mus rau cov duab sensor. Yog li, cov ntxaij lim dej no feem ntau siv rau hauv cov xwm txheej ci ntsa iab, suav nrog thaum lub hnub sawv thiab hnub poob thaum tus kws yees duab xav ntes cov sijhawm ob peb lub ntuj uas muaj xim. Cov xim no tuaj yeem ci heev, uas yuav ua rau poob ntawm kev nthuav dav hauv daim duab kawg; thiab ND lim tuaj yeem pab txo qis qhov kev nthuav dav (uas feem ntau hu ua blowout hauv daim duab). Cov kws yees duab kuj siv ND cov ntxaij lim dej thaum lawv xav tsim cov duab pom ntev lossis txo qhov nrawm ntawm qhov chaw ci ntsa iab. ND cov ntxaij lim dej tuaj ntau yam 'qhov tsaus ntuj' thiab feem ntau sau npe ND (qhov twgyog qhov sib npaug ntawm tus lej). Piv txwv li, thiab ND8 lim txo txog ⅛ ntawm lub teeb uas taug kev los ntawm lub lens mus rau cov duab sensor. Lub ntsiab tseem ceeb uas yuav tsum nco ntsoov yog tias hauv ND tus lej, tus lej qis dua, qhov teeb pom kev tsawg nws yuav tso rau hauv. Yog li, lub lim ND1 yuav tshwm sim yuav luag dub thiab yuav tso cai rau lub teeb me ntsis dhau mus rau cov duab sensor.
- Colored Filters: Cov ntxaij lim dej muaj xim yog qhov cuam tshuam me ntsis rau kev yees duab yees duab. Cov kws yees duab thaij duab tau siv cov xim sib txawv (liab, xiav, ntsuab, daj, txiv kab ntxwv) cov ntxaij lim dej thaum thaij duab dub thiab dawb los pab ua kom qhov tob hauv cov duab, vim tias tshem cov xim ntawm cov duab tuaj yeem txo qhov sib piv thiab shading uas qhia qhov tob. Cov xim sib txawv yuav nce lossis txo cov xim grey, uas tuaj yeem siv los ua kom tiav cov duab koj xav ntes. Cov ntxaij lim dej muaj xim kuj tau siv ntau hauv kev yees duab muaj tswv yim los ntxiv cov xim pleev xim rau hauv txoj kev kos duab.
Circular Polarizing Lim: Ib pawg ntawm cov lim dej polarizing yog cov lim polarizing ncig. Cov ntxaij lim dej no ua haujlwm zoo ib yam li cov txheej txheem polarizing lim, tab sis tuaj yeem hloov kho kom tau txais qhov zoo tshaj plaws pop ntawm cov xim thiab txo qhov glare. Tsuas yog ntxiv cov lim thiab tom qab ntawd tig nws kom txog thaum cov duab zoo nkaus li qhov koj xav kom nws saib. Ib qho tsis zoo yog tias cov ntxaij lim dej no tuaj yeem yooj yim raug tsoo lossis txav tau thaum koj txav lub koob yees duab ncig, uas txhais tau tias koj yuav tsum tau hloov kho lawv ntau zaus kom lub lim tig mus rau txoj haujlwm zoo meej
Circular/Variable Neutral Density: Lub voj voog lossis qhov sib txawv ND lim dej yog ib feem ntawm ND lim uas lub lim tau kawm tiav lossis muaj qhov tsaus ntuj ntawm qhov nce thiab txo qis. Hloov dua li hloov ND lim txhua zaus koj yuav tsum mus tsaus ntuj lossis sib zog nrog lub lim, koj tuaj yeem tig lub voj voog ND lim kom txog thaum cov nyhuv xav tau
Qee lub lim dej tuaj yeem muab tso ua ke kom ua tiav cov teebmeem sib txawv. Piv txwv li, koj tuaj yeem tso cov polarizing thiab ND lim, lossis koj tuaj yeem tso ntau theem ntawm ND lim kom mus txawm tias tsaus dua yog tias koj tab tom tua nyob rau hauv qhov kaj heev thiab xav tau qhov txo qis ntxiv hauv lub teeb.
Kuv Yuav Ua Li Cas Paub Lub Koob Yees Duab Lens Lim siv li cas?
Yog tias koj tseem tsis tau paub meej txog thaum twg yuav siv txhua hom lens lim (thiab tej zaum txawm tias koj yog), qhov zoo tshaj plaws uas koj tuaj yeem ua yog coj qee cov duab piv txwv siv txhua hom lim kom koj. tuaj yeem pom lawv hloov koj cov duab li cas. Nov yog ob peb lub tswv yim ntxiv kom nco ntsoov:
- cov ntxaij lim dej pheej yig yuav tsis ua haujlwm nrog rau cov lim dej zoo dua Qee cov lim pheej yig tuaj yeem ua rau vignetting thiab xim hloov, lossis tuaj yeem ua suab nrov rau hauv cov duab. Nco ntsoov ua koj cov kev tshawb fawb ua ntej koj yuav ib txheej ntawm lub koob yees duab lens lim, thiab xaiv cov ntxaij lim dej zoo. Txoj cai zoo ntawm tus ntiv tes xoo yog tias lub lim yuav raug nqi ib ncig ntawm 10 feem pua ntawm tus nqi ntawm lub lens uas koj siv nws.
- Qee qhov cuam tshuam koj tuaj yeem ua tiav nrog lub koob yees duab lens lim kuj tuaj yeem ua tiav hauv kev tsim khoom tom qab siv cov programzoo li Photoshop lossis Gimp. Sim siv lub lim thiab siv koj qhov kev kho kom raug tom qab tsim tawm kom pom cov nyhuv twg koj nyiam tshaj plaws.
- Lens cov ntxaij lim dej tuaj yeem tiv thaiv lub iav pem hauv ntej ntawm koj lub lens yog tias koj tua nyob rau hauv qhov xwm txheej hnyav. Yog tias koj npaj yuav nce toj ib ncig ntawm pob zeb, hauv cov xuab zeb lossis ntub dej, lossis hauv av ntau, lub lens lim thiab pab tiv thaiv pem hauv ntej ntawm koj lub koob yees duab lens ntawm av, plua plav, khawb, thiab txawm tias cov bangs npaj txhij txog. Qhov no tej zaum tsis yog ib qho laj thawj zoo los khaws lub lim txuas nrog koj lub koob yees duab txhua lub sijhawm, tab sis qee qhov xwm txheej, koj yuav ua tsaug yog tias koj ua.
